General Disclaimer

One or more of the Following Statements may affect this Document

This document has been reproduced from the best copy furnished by the 

organizational source. It is being released in the interest of making available as 

much information as possible.

This document may contain data, which exceeds the sheet parameters. It was 

furnished in this condition by the organizational source and is the best copy 

available.

This document may contain tone-on-tone or color graphs, charts and/or pictures, 

which have been reproduced in black and white.

This document is paginated as submitted by the original source.

Portions of this document are not fully legible due to the historical nature of some 

of the material. However, it is the best reproduction available from the original 

submission.

Produced by the NASA Center for Aerospace Information (CASI)
N84-16351

Unclas

11414

(NASA-CE-174509) ANTIHISTING KEROSENE;

BASE FUEL EFFECTS, BLENDING AND QUALITY

CONTROL TECHNIQUES Final Report, Aug.,1981

- Sep. 1982 (Jet Propulsion Lab.) 103 p

HC A06/3F A01 CSCL 21D 63/28

DOT/FAA/CT•83/83 Antimistin Kerosene. (JPL Publication 83. 96) g

Base Fuel Effects; Banding

and Quality Control Techniques

A. H. Yavrouian

J. Ernest

V. Sarohia

Jet Propulsion Laboratory

California Institute of Technology

Pasadena, California

Prepared for

U.S. Department of Transportation

Federal Aviation Administration

Through an Agreement with the

National Aeronautics and Space Administration

Final Report

January 1984

This document Is available to the U.S. public

through the National Technical Information

Service, Springfield, Virginia 22161.

a

US. Department of TronWortotion

Federal Aviation Administration

Technical Center

Atlantic City Airport, N.J. 08405

9

a

f6
TECHNICAL REPORT STANDARD TITLE PAGE

T'

I. Report No. DDT/FAA/CT-83/36 2. Government Accession No. 3. Recipient's Catalog No.

4. Title and Subtitle 5. Report Date

January 1984

Kerosene: Base Fuel Effects:

6. Performing Organization Code Blending

ng an

and Quality Control Techniques

7. Author(s) 8. Performing Organization Report No.

A. H. Yavrouian, J. Ernest, V. Sarohia I JPL Publication No. 83-96

9. Performing Organization Name and Address 1 10. Work Unit No.

JET PROPULSION LABORATORY

11. Contract or Grant No. California 'Institute of Technology

4800 oak Grove Drive DTFA03-80-A-00215

Pasadena, California 91109 13. Type of Report and Period Covered

Final: August 1981 -

September 1982

12. Sponsoring Agency Name and Address

U.S. Department of Transporation

Federal Aviation Administration Technical Center 14. Sponsoring Agency Code

Atlantic City Airport, New Jersey 08405

15. Supplementary Notes

Project Manager, Bruce Fenton, Engine/Fuel Safety Branch, Aircraft and Airport

Safety Technology Division, FAA Technical Center, Atlantic Cit y Airport, NJ 08405

!6. .".ystract This report addresses the problems associated with blending of the AMK additive with Jet A, and the base fuel effects on AMK properties. It also presents the results from the evaluation of some of the quality control techniques for AMK. The principal conclusions of this investigation are: 1) significant compositional differences

for base fuel (Jet A) within the ASTM specification DI655 that were expected to be

relevant `.o AMK properties were found, but with the exception of aromatic content,

these variations did not significantly alter the AMK characteristics; 2) higher aromatic content of the base fuel was found to be beneficial for the polymer dissolution at

ambient (20°C) temperature; 3) it was demonstrated that by using static mixer technology, the antimisting additive (FM-9) can be in-line blended with Jet A, producing

AMK which has adequate fire-protection properties 15-20 minutes after blending; 4) comparing the degradability of freshly blended and equilibrated AMK indicated that maximum

degradability is reached after adequate fire protection is obtained. At the dissolution equilibrium the degradability is highest; 5) the results of AMK degradability as

measured by filter ratio, confirmed previous RAE data that power requirements to degrade freshly blended AMK are significantly higher than equilibrated AMK; 6) blending

of the additive by using FM-9 concentrate in Jet A produces equilibrated AMK almost

instan*_ly. 7) nephelomet.ry offers a simple continuous monitoring capability and can be

used as a real time quality control device for AMK. 8) trajectory (jet thrust) and

pressure drop tests are useful laboratory techniques for evaivating AMK quality, and

their field applications as real time quality control devices should be evaluated

further.

17. Key Words (Selected by Author(s)) 18. Distribution Statement

Aircraft fires, aircraft safety, This document is available to the U.S Public

antimisting fuel, safety fuel through the National Technical Information

Service, Springfield, Virginia 22161

19. Security Classif. (of this report) 20. Security Classif. (of this page) 21. No. of Pages 22. Price

Unclassified Unclassified 103

JPL 0184 11180
Ri

o^m^L PA^

12, 3o ►

. C

|!! !

^ ^ |^ g ^h h^ |!^^ k ^^^ . ^

! -

!

^ 7 § !^„_ § ^.^, ^ |_r k §^!!^, ^ ||

< |

,R a mil,

n 7r' I . I . I . Tit ƒm/'rƒ/%'I'I

[ . , [ [ [ [

f EE o=._a; f

^ ^ A G h^! ^^| h!el=2 ;

^ . }

} ^ &_^ :§= S ! ^|, n ^^.8 b!! ^ !§ \ , g « \

$ § §

^ 2 _ § ! -

^ | |!!! |||^| ^^^^ $}|!!^{\\ ^ t^ `{

^ ^ \

I^ ^ ^^ ^ e d!a»^5 . \

k \q\\^//E

§

n

„
1'

ACKNOWLEDGEMENTS

This work presents the results of one phase of research carried out at

Jet Propulsion Laboratory, California Institute of Technology, Contract

NAS7-918, Task Order RE 152, Amendment 293, sponsored by Department of

Transportation/Federal Aviation Administration Technical Center, Atlantic City

Airport, NJ, under Agreement No. DTFA03-80-A-00215. The authors extend their

gratitude to Mr. B. Fenton, FAA Technical Center, Project Manager, for many

valuable technical suggestions throughout this program. The authors are

grateful to Dr. Robert Peterson and Mr. Richard George for their technical

assistance and advice. The assistance of Ms. L. L. Taylor, Mr. R. F. Haack,

Mr. S. Kazandjian, Mr. M. Smither, Mr. W. Bixler and Mr. B. Green in chemical

analyses, various tests, design, fabrication and the assembly of the

experimental setups is greatly appreciated.

iii
EXECUTIVE SUMMARY

'ire caused fatalities associated with impact survivable aircraft

crasnes are a major concern in aviation operations. In a typical aircraft

crash, fuel spilled from ruptured fuel tanks has the tendency to form a

fine mist which can be ignited by a number of sources present at the crash

site. Suppression of the tendency of the turbine fuel to form this mist by

modification of fuel can reduce the postcrash fire hazard and save lives.

Such a fuel has been developed by addition of Imperial Chemical Industries

(ICI) FM-9 polymer additive to the fuel. The addition of this highmolecular weight polymers to Jet A in concentration of about 0.3 percent by

weight changes the fuel to a shear-thickening liquid, th,:,,s suppressing

atomization and mist formation.

Tests conducted by the Federal Aviation Administration (FAA) have

demonstrated considerable promise in suppression of flame propagation in

simulated aircraft crash-landing fuel spillage tests. To be acceptable as

turbine fuel, the antimisting kerosene (AMK) must meet the various aircraft

operational requirements. It was therefore necessary to demonstrate the

feasibility of additive incorporation (blending) in the fuel at the refueling

point and to insure that the fuel blends remain homogeneous, develops firesuppressing properties within a short time (15-20 minutes), and are compatible

with the fuel and engine systems.

This report presents the results of a one year technical effort in the

areas on blending, effects of base fuel on AMK properties and quality control

techniques for AMK. The data is based on experiments using one large batch of

FM-9 slurry supplied by Imperial Chemical Industries for this program.

The principal conclusions of this investigation are:

1. Significant compositional differences for base fuel (Jet A) within

the ASTM specification DI655 that were expected to be relevant to AMK

properties were found, but with the exception of aromatic content, these

variations did not significantly alter the AMK characteristics.

2. The increase of the aromatic content of the base fuel was found to

be beneficial for the polymer dissolution at ambient (20°C) temperature.

3. It was demonstrated that by using static mixer technology the

antimisting additive (FM-9) can be in-line blended with Jet A, producing AMK

which has adequate fire-protection properties 15-20 minutes after blending.

4. Comparing the degradability of freshly blended and equilibrated AMK

indicated that maximum degradability is reached after adequate fire protection

is obtained. At the dissolution equilibrium the degradability is highest.

5. The results of AMK degradability as measured by filter ratio

confirmed previous Royal Aircraft Establishment (RAE) data that power

requirements to degrade freshly blended AMK are significantly higher than

equilibrated AMK.

iv
EXECUTIVE SUMMARY (Cont.)

6. Blending of the additive by using FM-9 concentrate in Jet A proL;uces

equilibrated AMK almost instantly. It was found that 5 percent concentrate of

FM-9 in Jet A was the maximum at which one still has a workable liquid.

7. Nephelometry offers simple continuous monitoring capability and can

be used as a real time quality control device for AMK. The data indicates

that it should not be used as the sole quality control device, but in parallel

with another instrument.

8. Trajectory (jet thrust) and pressure drop tests are useful

laboratory techniques for evaluating AMK quality and their field applications

as real time Quality Control devices should be further evaluated.

v
Lia..

^^tr 11! rF

^f.

^^t?

qr

TABLE OF CONTENTS

PAGE

ACKNOWLEDGEMENTS ----------------------------------------------------- iii

EXECUTIVE SUMMARY ---------------------------------------------------- iv

TABLE OF CONTENTS ---------------------------------------------••------ vii

LIST OF TABLES ------------------------------------------------------- ix

LIST OF FIGURES ------------------------------------------------------ xi

1. INTRODUCTION ---------------------------------------------- ------ 1

2. EFFECT OF BASE FUEL COMPOSITION ON AMK PERFORMANCE -------- ------ 1

2 .1 Background ------------------------------------------- ------ 1

2.2 Experimental Procedures and Results ------------------ ------ 3

2.2.1 Sources of Jet Fuel --------------------------- ------ 3

2.2.2 Antimisting Additive -------------------------- ------ 6

2.2.3 AMK Blending ---------------------------------- ------ 6

2.2.4 AMK Characterizations and Degradation --------- ------ 7

2.2.5 Results --------------------------------------- ------ 11

2.2.6 Discussions and Summary ----------------------- ------ 19

3. AMK BLENDING AND QUALITY CONTROL TECHNIQUES --------------------- 20

3.1 Background ------------------------------------------------- 20

3.2 Experimental Procedures ------------------------------------ 23

3.2.1 Materials ------------------------------------------- 23

3.2.2 Methods of Characterization and Degradation

of Blended Samples ---------------------------------- 24

3.2.3 AMK Blending Assembly ------------------------------- 25

PRECEDING PAG& BLANK NOT FILMED RAGE_E I INTENTIONALLY 81A1M(

vii
yi

TABLE OF CONTENTS (cont.)

PAGE

3.3 Experimental Results --------------------------------------- 27

3.3.1 Experimental Concept -------------------------------- 27

3.3.2 Development of the Blending Process ----------------- 28

3.3.3 Optimization of 2-Pass In-Line Blending ------------- 29

3.3,4 Evaluation and Development of

Quality Control Techniques -------------------------- 43

3.3.4.1 Filter Test, Cup Test, Nephelometry, FCTA -- 45

3.3.4.2 Pressure Drop and Trajectory Analysis ------ 58

3.4 Discussion and Summary 80

3.5 Conclusions - 83

REFERENCES ------------------------------------------------------••---- 85

APPENDIX A - AMK Received by JPL

APPENDIX B - Operating Procedure for Filter Ratio Test

APPENDIX C - Description of Filter Screen Device

APPENDIX D - Operating Procedure for FCTA Test

APPENDIX E - Operating Procedure for ICI Cup Test

r y . . .y

viii
V

LIST OF TABL__

Table 1. MASS SPECTROMETRIC ANALYSIS OF 150 0 to 288° C

KEROSENES------------------------------------------------- 4

Table 2. SELECTED SPECIFIC PROPERTIES OF AVIATION COMMERCIAL

JETFUELS -------------------------------------------------- 5

Table 3. CHEVRON JET A FUEL SPECIFICATION ANALYSIS -------------- -- 8

Table 4. EXXON JET A FUEL SPECIFICATION ANALYSIS ----------------- -- 9

Table 5. AMK BASE FUEL PROPERTIES -------------------------------- -- 10

Table 6. FILTER RATIO AND FLAMMABILITY OF FRESHLY

BLENDED AMK --------------------------------------------- -- 13

Table 7. INFLUENCE OF BASE FUEL AROMATIC CONTENT'ON

AMK. PROPERTIES -------------------------------------°------ 15

Table 8. INFLUENCE OF BASE FUEL AROMATIC CONTENT ON

DF_GRADABILITY OF FRESHLY BLENDED AMK -------------------- -- 17

Table 9. IN-LINE BLENDING: OPTIMIZATION OF THE TIME

BETWEEN TWO PASSES -------------------------------------- -- 30

Table 10, EFFECT OF MULTIPLE PASSES ON IN-LINE BLENDING ----------- -- 31

Table 11,. EFFECT OF PREWORKING SLURRY ON IN-LINE BLENDING --------- -- 32

Table 12. IN-LINE BLENDING: EFFECTS OF ADDING THE

SECOND MIXING STAGE ------------------------------------- -- 36

Table 13. IN-LINE BLENDING: RESISTANCE TO MECHANICAL DEGRADATION

OF DEVELOPING AND EQUILIBRATED AMK FUELS ---------------- -- 37

Table 14. CONCURRENT TURBIDITY AND FILTER RATIO MEASUREMENTS

ON DEVELOPING ONE PASS AND TWO PASS AMK FUELS ----------- -- 40

Table 15. CONCURRENT MEASUREMENTS OF UNDEGRADED SAMPLE

TURBIDITY AND DEGRADED SAMPLE FILTER RATIO ON

ONE PASS AND TWO PASS AMK FUELS ------------------------- -- 41

Table 16. IN-LINE BLENDING AT HIGH TEMPERATURE (60° C) ------------ -- 44

Table 17. CORRELATION OF TURBIDITY AND FILTER RATIO OF

AMK FUELS ------------------------------------------------- 46

PAGE

1x
x

LIST OF TABLES (cent.)

PAGE

Table 18. CORRELATION OF UNDEGRADED SAMPLE TURBIDITY

AND DEGRADED SAMPLE FILTIP RATIO OF

AMKFUELS --------------------------------------------- ---- 48

Table 19. EFFECT OF DILUTION OF AMK ON FIRE SUPPRESSION

AND CUP AND FILTER RATIO TESTS ----------------------- ----- 54

Table 20. EFFECT OF LOW TEMPERATURE DEGRADATION ON THE

FILTER TEST ---------------------------------°-------- ----- 57

Table 21. DETERMINATION OF EXTENT OF DEGRADATION BY ORIFICE

PRESSURE DROP ---------------------------------------- ----- 60

Table 22. EFFECT OF EXIT SECTION LENGTH ON THE

SENSITIVITY OF THE PRESSURE DROP AND

TRAJECTORY ANALYSIS TESTS ---------------------------- ----- 63

Table 23. DISCRIMINATION OF EQUILIBRATED AMK FUELS BY THE

TUBE PRESSURE DROP AND TRAJECTORY ANALYSIS

TESTS-------------------------------------------------- --- 64

Table 24. EFFECT OF TUBE EXIT SECTION DIAMETER AND SHEAR

RATE ON THE SENSITIVITY OF THE PRESSURE DROP

AND TRAJECTORY ANALYSIS TESTS ------------------------ ----- 65

Table 25. EXTENT OF DEGRADATION BY TUBE PRESSURE DROP

TESTING AND TRAJECTORY ANALYSIS ---------------------- ----- 73

Table 26. COMPARISON OF TUBE AND ORIFICE EXIT SECTIONS

FOR TRAJECTORY ANALYSIS AND PRESSURE DROP

TESTING USING DEGRADED AMK AND JET A ----------------- ----- 74

Table 27. TUBE PRESSURE DROP TESTING OF DEFECTIVE

FRESHLY BLENDED AMK ---------------------------------- ----- 75

Table 28. TUBE TRAJECTORY ANALYSIS OF DEFECTIVE

FRESHLY BLENDED AMK --------------------------------------- 76

Table 29. TUBE PRESSURE DROP AND TRAJECTORY ANALYSIS OF

AMK DILUTED WITH JET A ------------------------------- ----- 78

Table 30. TUBE PRESSURE DROP AND TRAJECTORY ANALYSIS OF

AMK DEGRADED AT LOW TEMPERATURE ---------------------- ----- 79
FIGURE CAPTIONS

PAGE

Figure 1. DENSITY VS. PARAFFIN CONTENT OF GAS TURBINE FUELS (150-288° C

FRACTION); FROM REFERENCE 2. ------••-------------------------------- -- 2

F i gure 2. SCHEMATIC DIAGRAM OF THE FLAMMABILITY COMPARISON TEST APPARATUS

(FCTA)• ---------------------------°-------------------------------- -- 11

Fi g ure 3. EFFECT OF BASE FUEL ON FILTER RATIO OF 0.3% AMK, ------------------- -- 14

r

Figure 4. INFLUENCE OF BASE FUEL AROMATIC CONTENT ON FM-9 DISSOLUTION RATE. -- -- 16

Figure 5. DEGRADABILITY OF FRESHLY BLENDED AMK. ------------------------------ -- 18

Figure 6. TYPICAL AIRPORT HYDRANT SYSTEM (FROM REFERENCE 2). ----------------- -- 21

Figure 7. IN-LINE BLENDING APPARATUS. ---------------------------------------- -- 25

Figure 8. CUP TEST RESULTS FOR ryK FUELS PREPARED BY IN-LINE BLENDING. ------- -- 33

Figure 9. FILTER TEST RESULTS FOR AMK FUELS PREPARED BY IN-LINE

BLENDING. ------------------------•-- ---------------------------------- 34

Figure 10. TURBIDITY MEASUREMENTS ON IN-LINE BLENDED AMK FUELS. --------------- -- 39

Figure 11. DEGRADABILITY OF IN-LINE BLENDED AMK FUELS. ------------------------- -- 42

Figure 12. CORRELATION OF TURBIDITY AND FILTER RATIO OF IN-LINE

BLENDED AMK FUELS. ------------------------•------------------------ -- 47

Figure 13.. CORRELATION OF TURBIDITY AND DEGRADABILITY OF IN-LINE

BLENDED AMK FUELS. ------------------------------------------------- -- 50

Figure 14. CORRELATION OF CUP TEST AND FCTA THERMOCOUPLE DATA FOR DC-10 FUEL

SYSTEM SIMULATOR AND BLENDER DEGRADED SAMPLES. --------------------- -- 51

Figure 15. CORRELATION OF FILTER TEST AND FCTA THERMOCOUPLE DATA FOR DC-10

FUEL SYSTEM SIMULATOR AND BLENDER DEGRADED SAMPLES. ---------------- -- 52

Figure 16. CORRELATION OF FILTER TEST AND FCTA CALORIMETER DATA FOR DC-10

FUEL SYSTEM SIMULATOR AND DLENDER DEGRADED SAMPLES. ---------------- -- 53

Figure 17. INFLUENCE OF DILUENT ON CORRELATION OF CUP TEST VOLUMES

WITH FCTA FIRE TEST. --------------- --------------------------------- 55

Figure 18. EFFECT OF DILUTION WITH JET A ON AMK FLAMMABILITY. ----------------- -- 56

Figure 19. PRESSURE DROP OF AMK FLOWING THROUGH AN ORIFICE SHOWING THE

CRITICAL SHEAR RATE TRANSITION. ------------------------------------ -- 58

Figure 20. EFFECT OF TUBE EXIT SECTION DIAMETER AND SHEAR RATE ON THE

SENSITIVITY OF THE PRESSURE DROP TEST- ----------------------------- -- 66

xi
FIGURE CAPTIONS (CONT.)

PAGE

Figure 21. EFFECT OF TUBE EXIT SECTION DIAMETER AND SHEAR RATE ON THE

SENSITIVITY OF THE TRAJECTORY ANALYSIS- -------------------

Figure 22. DISCRIMINATION OF EQUILIBRATED AMK FUELS

BY TUBE TRAJECTORY ANALYSIS- ----r--------------------------

Figure 23. EXTENT OF DEGRADATION BY ORIFICE PRESSURE DROP TESTING. ---

----- 67

----- 69

----- 71

xii
1. INTRODUCTION

Interest in reducing the fire hazard in aviation fuels has existed

almost since the beginning of aviation history. With the advent of the jeiengine and the subsequent change to kerosene-type fuels, there has been si g

-nificant safety improvements. However, past studies have shown that severe

fire hazards still exist with any hydrocarbon fuel when it is sufficiently

mixed with air at certain fuel/air ratios, as may be present during impactsurvivable aircraft crash landings.

During the past few years, studies by Federal Aviation Administration

(FAA) and other government agencies have shown that the hazards from aircraft

crash fires might be significantly decreased if an antimistin0 fuel could be

utilized (reference 1).

The approach to AMK fuels is to modify commercial jet fuels with a high

molecular weight polymer additive that would change the fuel into a shearthickening liquid. Fuels containing long-chain molecules of antimisting polymer have time-dependent rheological properties, including tensile viscosity

and shear-thinning and thickening behavior. The rheological characteristics

of this type of fuel have indicated considerable promise in suppression of

flame propagation under simulated aircraft crash landing fuel spillage tests.

An experimental study has been undertaken at the Jet Propulsion Laboratory :,,, determine the changes in mist characteristics, flame propagation charact f ,:°i't.,cs, combustion performance, low temperature behavior, base fuel

Rr'--cts, etc., which may result because of the use of antimisting fuel as compared to neat Jet A. This report discusses the base fuel effects, blending

and quality control techniques for antimisting fuel. Unless otherwise stated,

the experiments discussed below were performed with Jet A containing the antimisting additive FM-9" with carrier fluid developed by Imperial Chemical

Industries (ICI). The FM-9 polymer is available from ICI in a slurry formulation under the tradename of AVGARD. Appendix A shows the analysis of the AMKFM9 samples received from ICI during the course of this investigation. This

research effort has been broadly divided into two sections as follows:

A. Effect of Base Fuel on Performance of Antimisting Additive.

B. Evaluation of Blending and Quality Control Techniques. 

These areas are discussed in detail in the following sections.

2. EFFECT OF BASE. FUEL COMPOSITION ON AMK PERFORMANCE

2.1 Background

The properties of the AMK depend on the characteristics of the basi

fuel used in the formulation. The anticipated worldwide use of AMK will

require the use of base fuels from a variety of sources. Jet fuel properties

are influenced by the sources of crude feedstock and the refining process

used in the production of jet fuels. This is illustrated by the typical

density-paraffin content curve fo, , the kerosene fractions (150° to 288°C boil1 : 
7

ORIGINAL PAGE IS

OF POOR QUAL17Y.

ing range) of different crudes (Figure 1). The aromatics that appear in the

150 0 to 288° C commercial jet fuel fraction are a mixture of single-and multiring compounds, the concentrations of which are uniquely dependent on the

crude itself. Mass spectrometric data on the kerosenes from the crudes of

Figure 1 and Table 1 illustrate the wide range of aromatic types possible.

Aithuugh the total concentration of aromatics in these aviation cuts does not

exceed 25 percent, the atio of single-ring to muiti-ring compounds varies

considerably, a factor of considerable importance in combustion behavior.

PARAFFINS, %

Figure 1. DENSITY VS. PARAFFIN CONTENT OF GAS TURBINE FUELS (150-288° C

FRACTION); FROM REFERENCE 2.

Jet engine fuels are substantially 100 percent hydrocarbon mixtures and

any given fuel may contain several thousand individual hydrocarbon compounds.

These hydrocarbons are divided into four classes: paraffins, cycloparaffins,

aromatics, and olefins. Paraffins and cycloparaffins are very similar in most

of thr;r properties and together make up 75 to 90 percent of most aircraft

fuel. Only very small quantities of nonhydrocarbon compounds, rarely exceeding one percent, are likely to be present in aircraft fuels.

M

E

V

a

N

Z

W

a

2
C

i

While the distribution of hydrocarbons found in petroleum-derived fuels

varies from one crude oil source to another, the refin=r can meet the physical

and thermal property requirements of aircraft use by control of refining

methods.

Aviation turbine fuels are blenoed from straight-run distillates; the

distillation cut-points must be closely controlled to yield a product that

meets the requirement. Blending of two or more distillates is carried out to

match as closely as practical to the various specification limits. At this

point, additives may be introduced, e.g. antioxidants, metal deactivators,

corrosion inhibitors, etc.

With aircraft fuels, the global nature of jet aircraft operations mandates that the fuel quality be closely controlled. Specifications tend to be

industry standards issued by a government body or a consensus organization

such as American Society for Testing and Materials (ASTM) rather than manufacturer's requirements. In Table 2 are listed some of the requirements.

During distribution and handling, the preservation of the quality of the

fuel between the refinery and the point of use is an important but difficult

requirement. The difficulty arises from the complicated distribution systems

of multi-product pipelines and tankers which move fuel and sometimes introduce

contaminants. The importance is reflected by the sensitivity of gas turbine

engines and fuel systems to water, corrosion products, metal salts, microorganisms and other extraneous materials that can be introduced by the distribution system.

The compositional differences within the specifications and the differences in handling the fuel are expected to alter the characteristics of fuel

containing antimisting agents. The purpose of the program was to make a preliminary assessment of the base fuel effects. The research effort was divided

into the following subtasks: identification of types and sources of jet fuels

used in the U.S., rheological testing of undegraded fuels, testing of degraded

fuels and antimisting testing of undegraded fuels. The results of these

findings are discussed below.

2.2 Experimental Procedures and Results

2.2.1 Sources of Jet Fuel

The Oil and Gas Journal identifies approximately 30 domestic (reference 3) and 95 foreign crude oil suppliers (reference 4). A detailed survey

of aviation turbine fuel properties and their trends is contained in references 5 and 6.

In order to select representative base fuel samples a limited survey of

local (Los Angeles) jet fuel suppliers was done. The following local suppliers of Jet A were contacted: Exxon Oi; , Co., Gulf Oil Co., Chevron Oil Co.,

and Union Oil Co. In addition, contacts and attempts to obtain additional information were made with their research and marketing departments. Furthermore, several local airports were contacted and information on their jet fuel

procurement procedures was obtained.

3
1

ORIGINAL PAGE 19

OF POOR QUALITY

Ln

o r: .-^

n co

n

o

v tv rl

m co Ln Lo

n ri

n

M

N

N

m

i

OM O) 01

n

Q =D

n

•LU

n

01

MM

d 00

M l0

M

O

N

N .-1

0) dF

OM

O t0 01

O t0 .ti d•

to

N ti

L

M

M 4')

O

N ^^-I-I

Y3L 0 co 01

M 00 00 0) 00

n Ln

nc0

M

N .N-1

M

O

.^-•

1^

O 0) LO

N

O rl O\

rL t0 O\

N

1 LI; •ti 1 co d- N y M M M M 01 01 O t0 M

b

n

in

N

'""L 01

N

O

r~•L

N ti 41

Ln Cl al 01 O)

M

n 0) 00 1 V1 N N i•• N M r

co ti .M-1

C

Ln et .^

O

O

O co

00Ln of•f

N

N

.-L Ln d' r•

N

O r) .--L

U

I-L

04-Q co d'

N

01

M d• .-L

4

O

N . N M O Ln n N N 00

O

N

W

m .4•L

WM 00 ct

M

O

W

N

H

N

d

n C) tp rl

M .r

O r1

N

C c0 t0

n rL LD d'

N

O

ti ti

S

OD

ak

n am

va

d• r,

cn0

b

O

a

O c0 t0 r-1

O

r

r

N

N C OI

c

c

iy

C

Y O)

N

U

3

0

C

^ 

N •r

c

3

C

N lT

LC •L

a

4.. 'r O)

C V- C 4- 

7

N

r

°

L

C •r 4- 10 L •L L L

O

Ww • r

L

N

Nm m^0J

V

mL no

maol m 

O

r 1 O n.3 ++ M o 3

v

L. C^ 0 3 O N

m

c

3 ++

n

u

m

LnWZW

LnO

ui

uiN4YU

00

coN1 0OLnN

u- C) N.-L NYQZ4UCHWOHUWOLh

Ln

LnQN

01 amH

4
U

Table 2. SELECTED SPECIFIC PROPERTIES OF AVIATION COMMERCIAL JET FUELS

Civil

ASTM D1655A

Jet A Jet B

kerosene wide-cut

Characteristic

composition

aromatics, vol % max

**

20

**

20

sulfur, wt% max 0.3 0.3

volatility

dist.10% rec'd 204

temp. 50% rec'd 188

max ° C end pt 300

= flash pt, " C min 38

vapor pressure at 38° C, kPa 21(3)

max (psi)

density at 15° C, kg/m3 775-840 751-802

fluidity

freezing pt, ° C max -40 -5U

viscosity at -20° C, max, cSt 8.0

combustion

heat content, MJ/kg, min 42.8 42.8

smoke pt, mm, min 20 20

stability

test temp. *** * C min 245 245

*

**Full specification requires other tests.

***Fuel u to 25 vol% aromatics mayy be supplied on notification.

Thermapl stability test by ASTM D3241 to meet 25mm Hg pressure

drop and Code 3 deposit rating.

F^

5
The manufacturers can distribute fuel directly from the local refineries

to the airports via a pipeline. In the Los Angeles basin this is done by

Chevron and Union Oil Co, which pipe fuel from their refineries in El Segundo

and Wilmi , !gton to LAX. In addition, the County of Los Angeles buys and resells Jet A to a variety of small airports. Furthermore, large quantities

of Jet A are .old by brokers. Fuel is also sold by oil com p anies which do not

have local manufacturing facilities but buy the fuel from the producers on an

exchanca basis. In the case of Exxon Oil Co., the fuel is exchanged in large

quantities from Union Oil and Chevron and marketed as Exxon brand Jet A. In

return, Union Oil and Chevron get Jet A from Exxon in states where Ur-V on has

manufacturing facilities. The identification of Jet A is further complicated

during the storage of the fuel where fuel storage tanks may often contain fuel

from different suppliers.

The acceptance of the fuel by the user is based on the criterion that

the fuel must meet the ASTM D 1655 specification requirements for commercial

fuels. This prescribes test limits that must be met by the refiner who manufactures fuel; however, it is customary for fuel users to define quality control limits for fuel at the point of delivery. Quality control limits are

also met by third parties who distribute and handle fuel. Tests on receipt at

airport depots include appearance, distillation, flash point (or vapor pressure), density, freezing point, smoke point, corrosion, existing gum, water

reaction, and water separation. Tests on delivery to the aircraft include

appearance, particulates, membrane color, free water and conductivity.

The specifications have been developed to ensure satisfactory handling

properties, performance and adequate availability, but the nature of petroleum

is such that marketed fuels may vary considerably in physical properties and

still meet the specification requirements. In order to illustrate variations

to be expected in the properties of fuels of the same grade, representative

d?ta have been compiled in Tables 3 and 4. The values shown are representative of current production and all may vary within a modest range. Three fuel

samples were obtained, one each from Chevron, Exxon, and Gulf. At the time of

purchase, we were informed by Exxon that their Jet A was manufactured by Union

Oil Co. These jet fuels were analyzed in the relevant ASTM test categories.

Table 5 presents the results. Control runs were made using ICI-supplied Jet A

lot RMH 11118. This base fuel has 17.0 percent aromatics (ICI data) and is

purchased by ICI from Gulf Oil in New Jersey.

In order to evaluate the influence of higher aromatic content of the

base fuel or the properties of AMK, a fifth base fuel with higher aromatic

content was prepared. The fuel was made by adding 10 percent by volume of

tetralin to RMH 11118 Jet A and the new fuel was designated RMH 11118HA.

Except RMH 1118HA, the fuels selected in this program represent jet fuels

which are in everyday use, thus the properties of AMK prepared using these

fuels should indicate where it is feasible to use jet fuel from different

origins.

2.2.2 Antimisting Additive

The antimisting additive FM-9 used in this program is a proprietary fuel additive developed by Imperial Chemical Industries. The FM-9 is a

high molecular weight polymer with specifically designed properties for use
with jet fuels. The additive is supplied in the form of a free-flowing powder

or as a dispersion called standard ANIK slurry. An improved version of this

slurry is now available from ICI, Americas Inc. under ehe tradename of AVGARD.

The slurry composition is also proVrietary and contains 33.percent (w/w) of

FM-9 polymer in a carrier fluid containing mostly glycol and some amine.

For preparation of various samples of AMK using various base fuels, 35

lbs (lot N H273-1009) of standard slurry was prepared by ICI and shipped to

JPL. Only this batch of slurry was used in the program. The in-house prepared AMK was compared with AMK prepared by ICI in 0.3 weight percent concentration. Appendix A lists the AMK batches received by JPL.

2.2.3 AMK Blending

The addition of the antimisting additive to the various base fuels

was done in the JPL in-line blending apparatus. Detailed description of the

process and the apparatus is given in section 3.2.3. All batches of AMK contain 0.3 percent of the additive and were prepared in the 2-pass, 5 minutes

apart mode.

2.2.4 AMK Characterizations and Degradation

V

To assess the quality of the antimisting fuel, two standard

methods, the filter ratio test and Flamability Comparison rest Apparatus

(FCTA.), have been used extensively. These tests have been utilized to determine the dissolution rate of the additive in the fuel, the degree of fire protection and to distinguish one fuel batch from another, as well as to evaluate

the degree of restoration (degradation).

2.2.4.1 Filter Ratio Test

A filter ratio device (standardized by the U.S./United Kingdom

AMK Technical Committee) was utilized as the primary method of measuring viscosity properties. The details of this test are given in Appendix B and the

description of the filter ratio device is given in Appendix C. The filter was

a Dutch twill woven material with absolute pore size of 16 to 18u. A rubber

stopper was placed under the filter outlet and the tube filled until it overflowed with the reference fuel. The stopper was removed and the time required

for the meniscus to pass between the two reference marks was measured. All

the reference fuel was allowed to flow out of the device. The stopper was

then replaced and the procedure repeated with the antimisting kerosene test

fuel. The remaining fuel_ was discarded. The ratio of the time for the antimisting kerosene to flow between the two marks and that for the reference fuel

was calculated and reported as the filter ratio (FP.).

2.2.4.2 Flammability Comparison Test Apparatus (FCTA)

The FCTA, shown schematically in Figure 2, is described in detail in reference 7 and reference 8. Air is released from a pressure vessel

through a sonic orifice into a straight tube, where it atomizes a small jet of

fuel. The spray issues through a conic?', diffuser into ambient air and is

7
ORIGINAL PAGE 18

OF POOR QUALITY

Na-• NJdZ4ZO

F-dU

lLHUWdNJwwQ

t-W

itZOKwT

0 00

C3

00 NO n h0 r-1 .nO n a

mb N N

I O

•

a

0 1-;O M d -:r -zt Ln NN •rih +N 1 a o o M . r 11 N O h t 0 t 0 h O O

r Ol In

N h O M to

W d' 1 '-I •--1 N N N br

00

O O N to O

O

to

O toO -1 'n O co rt of d' .-^ r t N rl M t0 r-I t0 r ID M d' g 11 

O

u d' ra 

•r v rl

N • 

•

r • Op d' N Z O t0 N t0 rl

N0

m Ln M :

N 1I+ O to t0

b Id' 1 '-1 NNNN

CL

cu Y

O O O O O

m O M

O t0 O to Ot

J Nd' M U9 OD

N M v v v 00 to

to .-1 O 1I • vM vt • •^ O

r Ol O N

N

O co O Cl) to

m d' d'

N N N N N

N

1 O

O to t0 O O

7 O to d'

O rt M co t0 O

r OO .-I rl

1 t.t) r-I d' t0 d' M M O M M d' to rt .-^

O zrN

r

N

C ^OOto

N NOO

—co —CD

OM d'

N

Co tO t 0 0) M l D

2 d• 1 '-I .-^ .-I N N C to O n 000 7 O t 0 O - d' O h

C" N .+ v U'1 I ^ tp tD 

CO

M

m y d' to d'rl N In N ^N N

N7n

v G: OO rl d• 

N O O d' d' M t0

d' d- rl rl N N N

W

1

o to

O in to o0

C

O d'O d' O W N

O O t0 1 0

O

O .m Lo-e

L

v OO .-a to 

N .-r

u N O M

N

O d- h C1 --i d' d- h O d' h LL I r NNN

u

LoOUdCOuvN

coh
Table 4. EXXON* JET A FUEL SPECIFICATIONS ANALYSIS

Aromatics, % volume 19

Mercaptan sulfur, % weight 0.0003

Sulfur, % total weight 0.05

Initia -boiling point, ° F (° C) 325(163)

10% evaporated, ° F(° C) 355(179)

20% evaporated, ° F(° C) 364(184)

50% evaporated, ° F(° C) 397(203)

90% evaporated, ° F(° C) 490(254)

Final boiling point, ° F(° C) 520(271)

at 400° F(204° C), percent boiled off 53

Flash point, ° F(° C) 115(46)

Gravity, °API at 60° F 42.0

Specific gravity @ 60° F(15.6° C) 0.816

Freezing point, ° F(° C) -48(-44)

Viscosity @ -30° F (-34.44° C),

centistokes 7.9

Aniline-gravity product 6,500

Heat of combustion, Btu/lb 18,600

Luminometer No. 46

Smoke point, mm 21

Existent gum, mg1IO0 ml 0.2

Particulate matter, mg/liter <1

Free water, ppm <30

WSIM 97

Thermal stability:

Filter P, inches, Hg 0.1

Preheater deposits No. 0

c

*Data from Exxon turbofuel A data sheet DG-1C

9

t-Nomp._ _ _-
Table 5. AMK BASE FUEL PROPERTIES

PROPERTY EXXON GULF CHEVRON ASTM

Gravity, ° API at 60" F 38.9 41.4 40.7 D 1298

Freezing point, ° C -540 -44.5 -44.0 D 2386

Viscosity (-20° C), cSt 5.95 5.74 5.83 D 445

Aromatics, vol. % 20.7 20.1 19.3 D 1319

Napthalenes, vol. % 1.6 2.7 2.1 D 1840

Distillation, ° F D 86

Initial B.P. 340 342 325

5% 369 368 350

10 377 374 360

20 388 386 370

30 399 398 390

40 409 401 406

50 417 418 420

60 426 430 432

70 436 443 448

80 448 458 464

90 466 478 488

95 481 496 512

Final B.P., ° F 509 516 544

Distillation Residue, % 1 1 1

Recovery, % 99 99 99

Distillation Loss, % 0 0 0

10
ORIGINAL PAGE 19

OF POOR QUALITY

ignited by a butane torch. The fuel is delivered by a single stroke displacement pump, and issues through an upstream facing elbow with an inside diameter

of 0.52 cm. The inside diameter of the straight mixing tube is 2.66 cm. The

air mass flow is controlled by varying the air pressure and the fuel mass flow

is controlled by a constant speed actuator that regulates the fuel pump. Once

the air pressure and speed control are set by the operator, the operation of

the apparatus is controlled by an automatic sequencing switch. Appendix D

describes the JPL operating frocedure for FCTA test.

2.2.4.3 Degradation of AMK

The degradation of AMK samples by a kitchen blender prepared

from various base fuels is described in section 3,2.2.5. In an alternate

technique, samples were degraded by a continuous flow single pass degrader

which utilized a pressure drop across a needle valve. After degradation, the

samples were characterized by FR.

2.2.5 Results

j The properties and sources for the various base fuels used for

production of AMK were discussed in the previous sections. The preparation of

the samples was done in JPL's in-line blending apparatus. Two parallel control runs, using ICI-supplied Jet A (RMH 11118) were prepared for comparison

and reproducibility evaluation. They indicate that the apparatus produces AMK

with FR of 26f 2 fifteen minutes after blending using RMH 11118,

To evaluate the influence of higher aromatic content of the base fuel on

the properties of AMK, a base fuel with higher aromatic content was prepared

DISPLACEMENT PUMP

Figure 2. SCHEMATIC DIAGRAM OF THE FLAMMABILITY COMPARISON TEST APPARATUS

(FCTA).

i

11

t=
by adding 10 percent (v/v) of tetralin to RMH 11118. This fuel was designatQd

RMH 11118HA. For preparing the AMK, standard slurry of FM-9 supplied by ICI

was used.

All six batches (1 kg each) of AMK produced from various base fuels were

also characterized by FCTA. In addition the AMKs prepared from RMH 11118 and

RMH 11118HA were tested for their degradability at various times after blending. The AMK was degraded for 30 seconds in a kitchen blender and the degraded samples were characterized by FR.

One set of data is presentee' in Table 6, including times after blending,

FR and FCTA data. In addition the filter ratio vs. time after blending is

shown in Figure 3. The data indicate that all filter ratios fall in a very

narrow range. Judging from the filter ratio the so-p.roduced AMKs are very

similar to each other. The FCTA data presented in Table 6 confirm that the

fire protection capabilities of the AMKs are almost identical. They also indicate that the fuels may have some fire protection capability well before

filter ratios have equilibrated, but that at least one hour of development is

necessary before full fire protection capability is obtained.

The data from evaluation of AMK prepared from Jet A with higher aromatic

content are presented in Table 7 and Figure 4. The data indicate that AMK

with higher aromatic content gives significantly lower filter ratio, e.g. 24.7

vs. 41 for RMH 11118-based AMK. The filter ratios are also lower during the

process of dissolution of the polymer in the fuel. The FCTA results indicate

the same fire protection capability.

Figure 4 also shows that the rate of dissolution of the polymer in Jet A

with higher aromatic content is faster and equilibrium filter ratios are

reached sooner. The equilibrium filter ratio of about 27 is reached in approximatel.y 2 hours in the case of RMH 11118HA-based AMK, while the equilibrium ratio of about 41 is reached in 16 to 18 hours in the case of RMH 11118-

based AMK. Visual observ ation on samples turbidity during the dissolution of

the polymer, indicated that the AMK from RMH11118HA becomes clear faster than

the rest of the sampl -2s.

As indicated above, experiments were performed to evaluate the influence

of the higher aromatic content on the degradability of freshly blended AMK.

For comparison purposes 3-month old AMK RMH1-172 was also degraded for 30

seconds in the same blender. The fi;tsr ratio value of 4.4 for this sample

was considered to be the one which should be reached, by the freshly blended

AMK if it has reached maximum degradability. The data are presented in Table

8 and Figure 5. As expected, the AMK made from RMH 11118HA reaches filter

ratio of 4.4 sooner than AMK made from RMH 11118. If the times for the AMK

fuels to reach equilibrated filter ratios in Figure 4 are compared with the

times where the curves intercept the 90 percent line in Figure 5, it can be

seen that these times are approximately the same. In other words, AMK made

from RMH 11118HA reaches its maximum filter ratio in about 120 to 140 minutes

in Figure 4 and also reaches it maximum degrability in about 140 minutes, as

seen in Figure 5. This is proof of an earlier concept that the degradability

and the dissolution of the polymer are connected and that the increase in the

dissolution rate will shorten the time for reaching maximum degradability.

The data (Table 8, Sec. 3.3.3) also suggest that the power requirements to

degrade the polymer will be higher if the degradation is done before the

polymer has reached its dissolution equilibrium in the fuel.

12
ORIGINAL PAGE 15

OF POOR QUALITY

YdWZWJ

coJxNWWW0

h-1Jr-. m££CJWazdOHdaW

F-JWa

roH

F ` L i r 1

9 i L

b vl ^n rn N c

^ 

a

a ro

m

Ca

o

L V&-

rd

um

ro

E C C ro fa

O a

a

0

~ 'C r 00 to N e--1 ro rl L O

OU

m

u N fu N 

a pl^ tL0 CL 4J 41 .^ a A N d N N Z Am d N V U

a Q

O

O

O

O

O

U

O

b

N

N r1

N

0 3 ()

*^ aoN N

0

0

0 0000

HU L p W C a S

^

E ,4' .-a

o

c

o

Oo

0

ro a

n ,^ 00

L

O a 

Q

NV- •r

r ro 

O . ca

M

M 6. C r U--, a EL

a m

o 4-

c

t4- •r

ro

o ti

2

M

M

M

M

K C lL •r .0 EL

4+ m

^ C

O ro •r

I^

b

N 'O

N r-I

N

w C

N

N

N

N

OC • rr

N

y E a

m

m

J

oZ

W

Ox

=

r ti

d ac co 'w '" .-^

a

H 41

W

2

x

Z

fu a

U

£

m^

z

v^cacaLa

wa°

ror x

a•r

GNi^ ^c Y • r a

> 

d

c > 

a

E ro ¢

no(u

v z <n

x i^

13
Go 00

z==

Z 2==

0 J^«

W V V 1 "9

• 4 q XO

O

0

ORIGINAL PAGE 19

OF POOR QUALITY

Y

Q

M

O

W

O

O.r

4K

Z W

C JH

W

0 Z

Z O

W

ZW W J W

p

m N

W <ca

W

Q O 8 W r ^ UW

H WWW

M

v

L

m

u-

;•i

1 I I 0

^ s

o s ^^ d Q

01i" x31114

14
ORIGINAL PACE 19

OF POOR QUALITY

FR, 30 FR, 240 FR, 340 FR, 26 FR, 100

Jet A min. after min. after min. after hrs. after hrs. after

Base Fuel blending blending blending blending blending

RMH 11118HA 19.4 27.2 27 27.7 26

RMH 11118 25.5 36 36 41 41

i

N

L

Table 7. INFLUENCE OF BASE FUEL AROMATIC CONTENT ON AMK PROPERTIES

FCTA DATA

100 hrs. ifter blending

Jet A Set 200*

Set 900*

Base Fuel AT° C AT° C

RMH 11118HA 10 98

RMH 11118 20 110

*FCTA, Appendix D

t^

15

e ,--
_f0

x

O

°

Q

w co

r r

r r

r

r ^

a

X •

°

R $ in r

ouva aaiii^

ORIGINAL PAGE IS

OF POOR QUALITY

16

w

CCx

z

0

J

O

V)

N

cm

O

rn

F

W

Z

O

6N ~

I.- W

D H

Z ZOU

U

.-^

H

Z f

CD

D C Z

W J

J w

m uOC

W w

H

Q m

cW w

` O

t—

w

Uz

W

J

Ii

z

v

v

L

m

01

LL
YQOWOZWJ

6]rJx

V)wxw

LLOT

fr+JHmdOd

oC

17WzO

F-ZW

F-ZOU

URIGINAL PAGE 45

OF POOR QUALITY

Oo

roa

LL

X In

ra r-1

M

L >1 b 1

h ^D 00 !;1

Cn a tY 1 00 W LL 1 11 c 2 LL I LL

ex

M

M

^

tl_

r^O

O

h

,.-1 -0 r-1M

M

M

'-1

.r0

0

L •^

LLv ^+ N ro

N

h^

d b CJ

n

M

Lcr 41

en

w O

L •r

O 4+

V- ro In

N Ta O] ro 111 10 ^--^ L N mM M ^t

a rn

LL N

fm

GO

O

O

ti

ro KX

V LL

ro v 1.-+ cv

O rn

M

o

L 71 

4' 1 O1 co 01 Ot

0)a LL 1 1 0) ^ is LL 1 LL ^ 1

_N lD r1

h C'

^OM

M

M

,^

.r

d .--1

N

N

N

M

r-1

O

O L •.- L 6 k^

LL

m

N l0 O1

O cl

^c ¢ ro

M

MM

a

L

d Im

U- 4J

GIC

d O L•r VO.. cf

N

n co

co1 RS 01

hh I^

L

-

N

N

N

mM

a rn

LL 

v

v ^ i•1 G .--.

G^ Q N

w. .'- an •.

e

h

L 

E

..

.-

N

c S -G lff• i-I t\ r- Ol 1

N UJ ,.^

O

N r +^ rl E.- ryN 7 ro Y

F.°^ wnz I CO

ya

ro a

roLm

C1Ld

I.J

roO

I^

rozLa

LL

11 aW

17
100 

90 

80 

70 

'if. , 

8 60 

x 

- ~~~ 50 

'" '", 

3:'" 40 

30 

2fi'-

10 

0 

I 

-~~":--'---. 

r- .----.-~.___. --. .-r----. -,- -- (- - r- I -I -, -~ r-, T 

RMHI-I72 

x - At'lK FRO~l RMHll1

.- AMK FROM RHHlll

100 1000 

TIME AFTER BLENDING, MINUTES 

Figure 5. DEGRADABILITY OF FRESHLY BLENDED AMK. 
The dependence of degradability of AMK on base fuel type was further

evaluated by using Chevron, Exxon and Gulf base fuels. The AMK was prepared

again in the in-line blending apparatus using 1.5 kg batches of base fuel in

the mode of 2-pass blending with five minutes delay between passes. After

blending, the various AMKs were allowed to equilibrate for 24 hours and then

degraded. This time, degradation was done in the continuous flow single-pass

degrader which utilizes a pressure drop across a needle valve. The undegraded

and degraded fuels were characterized by their filter ratios. The data are

presented in the following cha;-t.

AMK made FR before FR after

from base degradation 24 hrs AP degradation

fuel after blending

Chevron 26 2000 psi 1.3

Exxon 27 2.000 psi 1.3

Gulf 32 2000 psi 1.3

The data indicate that the various base fuel AMKs degrade to the same

level (as measured by FR) and the influence of the base fuel on the degradability of AMK is minor, in fact not detectable, for these particular batches

of base fuel. It was expected that if the filter ratios of various base fuel

AMKs fall in a narrow range (±7), the degradability of the fuel should not be

much different. Comparison of the filter ratio data for these three batches of

AMK with the data for the previously prepared batches indicates that the

filter ratio is slightly lower for the last run. Although both sets of

batches are prepared by 2-passes 5 minutes apart, the latter batches are

larger (1.5 kg vs. 1 kg) and take a half-minute longer for the fuel to pass

through the apparatus at the maximum flow rate. This causes a slight reduction in the filter ratio due to the longer residence time.

2.2.6 Discussions and Summary

Limited survey of aviation turbine fuel manufacturing and distribution practices indicated a high level of complexity, quality control and

standardization. It also indicated that substantial variations within ASTM

specification D1655 that are relevant to AMK properties (see Table 5), can be

expected. Certain equipment or conditions of use may also permit a wider, or

require a narrower, range of characteristics than is shown by this specification. Of the various compositional differences within the specification, the

differences in aromatic content were considered most limiting and were studied

in more detail by increasing the aromatic content of the fuel. The rest of

the base fuels used in the program were purchased from the local suppliers and

had about the same percent (19 ±2) aromatics. The investigation was done on a

laboratory scale using only one batch of polymer slurry. With the exception

of the higher aromatic content base fuel, the rest of the Jet A fuels produced AMY, with relatively narrow range of properties. No significant dif4

19
ferences were observed in the samples' dissolution rate, blending and rheological behavior. The same observations were made for the fire protection properties and degradability (freshly blended or equilibrated) of the samples. No

formation of gel and gel settlement was observed with any of the samples and

all blends remained homogenous. It should be mentioned that all the experiments were done at 20° C.

The increase in aromatic content improved the polymer dissolution rate

and s.herefore shortened the equilibration time. Freshly blended samples were

less turbid and maximum degradability was obtained in shorter times. In the

area of filterability, the higher aromatic content significantly affected the

filter ratio measurements. The filter ratio for the undegraded fuel decreased

approximately two-fold as the base fuel aromatic content was increased from 17

to 27 percent. The corresponding filter ratios for the degraded fuels showed

the same tendency to decrease. No other significant differences were observed. In summary, the use of higher aromatic content base fuels was found to be

beneficial for the FM-9 dissolution rate at ambient (— 20° C) temperatures. The

conclusions of this Section can be found at the end of the report.

AMK BLENDING AND QUALITY CONTROL TECHNIQUES

3.1 Background

The introduction of jet fuel additives such as antioxidants, metal deactivators, corrosion inhibitors, etc., to the fuel is usually done at the refineries immediately after the fuel blending process and is carried out to

match the various specification limits. These additives are low molecular

weight, chemically stable structures and they survive the complex distribution

and handling process from the refineries to the airports. In the distribution

process extraneous materials such as water, dust, rust, etc., may be introduced into the fuel. The principal means of removing these contaminants are

tank settling and filtration. With aviation fuels, it is common practice to

install several stages of cartridge-type filter-coalescers between the storage

tank and the aircraft delivery point. Figure 6 is a s::hematic of a typical

airport fueling system. Filter elements of fiberglass and paper are designed

to coalesce water and remove particulates at high flow rates. Coalesced water

is prevented from passing with the fuel by hydrophobic barrier filters. These

are the processes and steps a fuel additive usually undergoes if added to the

fuel at the refineries. All the antimisting additives so far considered and

evaluated are high molecular weight polymers and as such are susceptible to

mechanical degradation after dissolution in jet fuel. Their ability to alter

the Theological properties of the fuel make AMK fuel blends more difficult to

filter than untreated kerosene.

Th p filtration considerations, sensitivity to bulk water and limited (-

4-8 months) shelf life all make the introduction of antimisting additives into

kerosene at any stage other than at the aircraft refueling point impracticable.

It is therefore necessary to demonstrate the feasibility of blending at the refueling point and to ensure that the fuel blend remains homogeneous, develops

fire-suppressing properties within a short time (15 to 20 min), and is compatible with fuel systems and other fuel additives. The nature of the blending

process is determined largely by the form of the additive itself. FM-9 antimisting additive is obtainable in a fine powder form. Some work in the past at

RAE in the U.K. has been done on the metering of the additive powder by suction

20
k y

Cf

KWQN

Kva

K0Q

Cke dWN 

WW

ol

ORIGINAL PAGE 1

OF POOR QUALITY

NWUZWzwwzE0

d'

LLfWHNYNzz0Y

F—z0azJ

_Ud

FUIL

V^ W

V

ZO

Q 1-

ou

LL N

t^

wONQKQdwNi zwHJ

u0FNZazwaO

zOQQdWNKw

I-JW

w0N ^. Ym

21
directly into kerosene. That work is reported in proprietary technical group

meeting memorandums and indicates that the powder tends to compact under these

conditions. In addition, the low density of such powders and possibility of

dust explosions pose handling problems. Therefore, blending of AMK directly

from FM-9 powder was not attempted during this research effort.

Currently at ICI, large quantities of AMK needed for evaluation and research purposes are produced by dissolving the powder directly in kerosene.

This method is a batch process and substantial variations in the quality of AMK

produced this way have been noticed in the past. As indicated previously, AMK

for field use needs to be blended at the aircraft fueling point and the consensus of opinion has been that the optimum method for making the fuel would be

the single-stage blending process, metering the additive in the form of a high

solid content dispersion in a carrier fluid. Dispersions can be treated as

viscous fluids, and liquid-liquid contact has an intrinsic appeal over solidliquid contact. The dispersion has been made available and is called AVGARD°,

supplied by ICI. The exact slurry composition is proprietary and contains 33 percent by weight of FM-9 Polymer dispe; in glycol/amine carrier fluid. Work on

the optimization of the dispersion of FM-9 slurry in jet fuel has been carried

out by ICI, by Shell Research Ltd, and by RAE. In addition, RAE has been using

slurry dispersion for development and evaluation of in-line blending processes.

The results from these investigations indicate that the slurry has satisfactory

properties (shelf life, viscosity, homogeneity, meterability, etc.). RAE has

also shown the feasibility of manufacturing antimisting fuel by an in-line

blending technique. However, the RAE tests suggest that the freshly prepared

antimisting fuel, blended via in-line techniques, although fire resistant, was

particularly difficult to degrade for some hours after blending.

In the search for a rapid dissolution technique, attempts by General

Technology Applications Inc., Arlington, Virginia, with FAA funding, have been

made to utilize cryofracturing for that purpose. In this process, when macromolecules are fractured in the presence of liquid nitrogen and when the comminuted particles are directed, under nitrogen, into a solvent, most of the

particles dissolve within a few seconds. The technique has been successfully

applied for rapid in-line dissolution of high-molecular weight (MW = 3.6 x 106)

polyisobutylene (PIB) in Jet A kerosene, but proved inapplicable to the FM9/Jet A system.

With the above considerations in mind, JPL research concentrated on

slurry blending of polymer and fuel for the production of AMK. The objectives

were (1) to address new prospects for polymer dissolution, (2) to demonstrate

an efficient in-line blending process built around a static mixer, (3) to demonstrate the feasibility of an in-line device constructed from off-the-shelf

equipment, and (4) to efficiently produce high quality batches of AMK to support the other in-house tasks.

As indicated above, the development of an equilibrated macromolecular solution will take time. An equilibrated solution is not a requirement per se,

but tests show that significant equilibration is necessary for antimisting behavior and especially for energy-efficient degradation. The quality control

assessment of fuel development is thus integral with the control of the blending process. It is also true that methods used to judge a blending process are

also AMK quality control methods themselves. For these two masons, the blending and quality control (QC) sections of this report are presented together.

22
Quality Control techniques are most important for the determination of

fire suppression ability and the determination of extent of degradability. It

is important to realize that the nature of AMK in these two cases is quite different. Tests which adequately characterize one type of AMK and give corresponding results in one case may not be adequate nor correspond in the other.

A corollary to the above categorization is our exclusion from this report of methods which might be considered QC methods but do not relate to

either the extent of development of freshly blended AMK or to the characterization of degraded AMK. For example, the extent of formation of low temperature gels is important to AMK compatibility with aircraft fuel management systems, but the gel test is not considered in this section.

The filter ratio test has been and continues to be a commonly used and

simple tool. It is least sensitive with highly degraded samples. The FCTA

test, using either a fast response thermocouple or a calorimeter sensor, complements it with its region of maximum sensitivity. Both test_ handle laboratory needs but are inappropriate for the field; the filter ratio test is not a

real-time test and is shock sensitive, while combustion tests are unsafe. New

QC tests must be relevant to routine, continuous airport use.

It should be noted that while fire tests are direct, most analyses determine fluid properties. What is actually required in AMK behavior is flammability suppression and flammability restoration. Unfortunately this behavior

is linked to several properties but to none rigidly.

Historically, ICI has introduced the cup test to assess the virgin

quality of equilibrated AMK FM-9 and RAE has developed the filter test to

assess the degradability of AMK FM-9. The UK-US Technical Group has since

examined many QC techniques. The cup and filter tests are particularly simple.

Fire tests such as the rocket sled (RAE), spinning disk (reference 9), FCTA

(reference 7 & 8), and various wing shear facilities directly gauge flammability behaviour. JPL report (reference 10) "Influence of Liquid Water and

Water Vapor on Antimisting Kerosene (AMK)" addressed several QC methods. The

AMK literature reports use of the Brookfield viscometer, capillary viscometery,

other viscosity methods, and some turbidity melsurements. The work (reference

11) with the Rheometrics Mechanical Spectrometer studied the time-dependent

shear thickening behaviour which is at the base of the mist formation process.

Recent attempts (reference 10 and 11) to characterize extremely degraded

samples for polymer fragment molecular weight involve Gel Permeation Chromatography and Pratt & Whitney's (reference 12) transition velocity technique.

Finally, the filter ratio test has been extended by the use of screens of various mesh sizes and Nucleopore filters (reference 12). In comparing the QC literature, it is important to remember the domain in which the methods were used.

We examined the following quality control techniques: filter ratio test,

cup test, pressure drop measurement across an orifice and a tube, trajectory

analysis downstream of an orifice and a tube, and nephelometry.

3.2 Experimental Procedures

3.2.1 Materials

All blending experiments started from slurry and jet fuel. In

every case, the slurry originated from ICI 35 pound lot #H273-1009. This

23
slurry is described in more detail in section 2.2.2. The slurry tended to

separate, and settle with a few percent of liquid appearing on the surface and

in voids. To ensure representative composition and to control the loss of

amine and glycol, the paste was mixed thoroughly with a spatula and 12-ounce

samples were taken as required. ICI Jet A was always used, RHM 10608 for the

first 17 experiments and RMH 11214 thereafter. The standard ctioices for

experiments in quality control were ICI AMK, lot RMH1-160, and RMH 11214 Jet A.

The quality control section also contains data on samples obtained from Douglas

Aircraft Corporation, which were from the compatibility study of AMK and the

DC-10/KC-10 fuel system. Additional data on samples can be found in reference

13. The source of any other fuel used is indicated in the report of the

individual experiment.

3.2.2 Methods of Characterization and Degradation of Blended Samples

3.2.2.1 Screen Filter Ratio Test and Orifice Flow Cup (ICI Cup Test)

The filter screen device was utilized as the primary method of

measuring viscosity properties and is described in section 2.2.4 of this

report. In the tables in this report, in those cases where the FR is reported

as "plugged", it will be in excess of 150. A detailed procedure for the cup

test is presented in Appendix E.

3.2.2.2 Pressure Drop and Trajectory Analysis Devices

Both pressure drop and trajectory information are available from

the same device. This device consists of a positive displacement driver, a tap

off to a pressure transducer, and an interchangeable exit section. The exit is

horizontal and set directly above the zero of a distance scale with which it is

aligned. The pump was a single stroke, non-reciprocating type to minimize sample degradation. The pressure tap is taken off of a section larger than any

subsequent diameter and is placed as close as possible to the exit section interlock. This ensures that the pressure measured is an index of the fluid resistnnce in the exit section alone. All data were collected manually, reading

pressures off a strip chart and noting the point of impact. To prove the concept quickly, a Sage Model 355 syringe pump (Orion Research, Cambridge, Mass.)

and feed off from a B-D Luer-Lok automatic syringe refill kit were assembled.

Standard syringe needles were used as tubes and truncated syringe needles as

orifices. The orifices had diameters from 0.5 to 2.5 mm and L (width)/D ratios

of about 1. The sample reservoir was a 100-cc ground glass syringe, the largest

available. Trajectory analysis was not performed with this first device.

The FCTA apparatus was modified to provide the second experimental arrangement. The front end plate with its sonic nozzle was removed and the exit

fuel line and check valve at the tee into the pump was disconnected. A closecoupled length of 1/4-inch tubing then replaced the fuel line with a pressure

transducer tee. This led either to, as in the first device, a Luer interlock

and syringe needles and orifices, or a piece of standard 1/4-inch tubing used as

an exit section. The tip was always one foot above the floor, horizontal to it.

The FCTA could be converted to and from this use in about half an hour.

-a

24
'i

ORIGINAL PAGE 19

'j 3.2.2.3 Turbidity

OF POOR QUALITY

The measurements were done with a model DRT-100 Turbidimeter manufactured by H. F. Instruments. The DRT-100 Turbidimeter is a continuous

reading nephelo-metric instrument which measures reflected light from scattered

particles in suspension and direct light passing through a liquid. The resulting ratioed optical signal is stabilized and amplified to energize a mete,

The instrument provides a linear readout of turbidity in nephelometric turbidity units, Note that JTU (Jackson Turbidity Units), FTU (Formazin Tu&Adity

Units) and NTU (Nephelometric Turbidity Units) are interchangeable. The data

in this report is presented in Formazin Turbidity Units because the DTR unit

was referenced to factory Formazin calibration.

.

3.2.2.4 Flamability Comparison Test Apparatus

This instrument was used for characterization of degraded, undegraded and developing samples and is described in section 2.2.4.2 of this report.

3.2.2.5 Sample Degradation

Unless otherwise indicated the degradation of the samples was done

in a kitchen blender (Hamilton Beach Scovill Blender with 5-cup [1.25 liter]

container). The sample size was always kept the same (300 ml) and samples were

degraded for 30 seconds at 22° C on the highest speed (liquefy). The degraded

samples were characterized by filter ratio and were always done within one

minute after the sample was degraded.

3.2.3 AMK Blending Assembly

The in-line blending setup which was used to produce AMK is presented in Figure 7. The apparatus had several variants and Figure 7 shows the

BASE

FUEL VALVE

TANK

SLURRY

INJECTION

PORT

PUMP STATIC MIXER

PRESSURE

TRANSDUCER

AND RECORDER

AMK

TANI:

BLENDER

VALVE 02 VALVE 03

Figure 7. IN-LINE BLENDING APPARATUS.

25
last. The in-line blending system consists of a slurry injection port, a pump

and the mixing elements (static mixer and blender). The entire system is made

from off-the-shelf components with the exception of the base fuel and AMK fuel

tanks. The injection port is part of the B-D Luer-Lok automatic syringe refill

kit. The pump drive module is a high flow rate, explosion-proof unit, Model RPF manufactured by (FMI) Fluid Metering Inc., Oyster Bay, N.Y. The RP-F unit employs a 1/4-HP motor with model RP-F-2 pump head module. The head is made of

316 stainless steel with sintered carbon for cylinder liner material. The pump

has maximum flow rate of 16 gph and a maximum pressure rating of 100 psi. The

pump has a simplified positive displacement mechanism based on a valveless

pumping mode and is recommended for handling semi-solid fluids and heavy

slurries. The main component of the system consists of a Static Mixer ® manufactured by the Kenics Corp. The device is simply a straight 1/4-inch stainless

steel tube, 9 inches long with a series of fixed, helical elements enclosed

within the tubular housing. The elements are fixed to the pipe wall, and the

trailing edge of one element is attached to, and forms a right angle with, the

leading edge of the next element. The helical design of the central element

causes a transverse flow to arise in the plane normal to the pipe axis. As a

consequence, fluid near the center of the pipe is rotated out toward the circular boundary, and vice versa.

Radial mixing and multiple flow separation is achieved in this manner.

The unit is an in-line mixer having no moving parts and no external power requirements; in addition the unit is amenable to quick changes, has low cost of

operation and hardly requires any maintenance. There are other motionless

mixers available on the market. The distinguishing feature of commercial

motionless mixers is the method whereby stream splitting is achieved. The

Kenics device was selected because of it's lower pressure drop.

In the second half of the program a Waring base blender was added to the

system. A stainless ste21, semimicro container (Eberbach 8580) with a maximum

working capacity of 250 ml was used. The container was adapted for a flowthrough operation by welding two 3/8-inch I.D. tubes to the wall of the container, one near the top and one near the bottom. The components of the inline blending system are assembled by flexible PVC tubing which gives some

see-through capabilities to the system.

In brief, the AMK blending consisted of weighing the appropriate amount

of slurry in a 20 ml B-D Plastipak® Luer-Lok tip disposable sy r inge and then

locking the syringe into the injection port. Care was taken that the slurry

did not contact the fuel; any wetting of the slurry with jet fuel at this

stage causes premature swelling of the slurry at the wetted surface and formation of transparent gel which make the consequent dispersion of the polymer

particles very hard. With valves #1, #2, and #3 closed, the required amount

of jet fuel is placed in the tank. After the pump and blender are turned on,

valve #1 is opened. With the opening of the valve, the slurry from the

syringe is carefully injected in the fuel line. The AMK is collected in the

tank, allowed to develop for the desired amount of time, then transferred back

to the Jet A tank and passed through the system for a second time. After the

second passage, the fuel is again collected and the time is recorded. For obtaining reproducible results, the time between the first and second passes

should be kept the same (*-5 sec). If samples are taken for evaluation before

26
the fuel is fully equilibrated, the time when they are taken should be recorded. It should be noted that the end of the second pass was always considered the start of the polymer equilibration process.

After each batch the system was cleaned by circulating jet fuel through

the system by pumping the fuel with valve #1 closed and valves #2 and #3

opened. The most popular batch size was one kilogram and the system was

always used at maximum flow rate.

More details about the in-lire blending system are given later in this

report.

3.3 Experimental Results

3.3.1 Experimental Concept

The considerations for choosing slurry blending of polymer and

fuel for the production of AMK were addressed in section 3.1. Also identified

were the difficulties of effectively degrading (restoring) freshly blended A11K

as the main concern in the area of AMK blending. The general concept was that

the degradability of the polymer (FM-9) in the fuel is directly related to the

rate of polymer dissolution in the fuel, or the maximum susceptibility to

energy-efficient degradation will be approached when maximum equilibration of

the polymer in the fuel is reached. In other words, the sooner the polymer

dissolves, the easier it will be to degrade.

The following general parameters which influence the rate of polymer

dissolution were identified:

polymer particle size

solvent (fuel) chemistry

polymer chemistry

mode of mixing

slurry viscosity

polymer particle porosity

solvent (fuel) temperature

polymer surface properties

degree of polymer particle

agglomeration

For most of the parameters, ideally, the best time for their optimization is during the polymerization and polymer isolation processes, where control over particle size, porosity, surface properties, etc. is greater and can

be varied. The scale at which jet fuel is used make; any attempt to optimize

the fuel (solvent) chemistry and temperature in order to accomodate any additive very impractical. Proprietary and patent restrictions and the above considerations limited JPL mainly to slurry/fuel mixing. The area of polymer

particle size is very important and it is known that it can greatly reduce the

dissolution rate of polymers in general. Attempts were made to reduce the

particle size in two ways. The first, using the in-line blender to disperse

the slurry, was to allow it to swell for ten minutes then break up the particles with a second pass through the moderate shear conditions of tire static

mixer. The second approach was to work the slurry prior to contact with the

fuel to eliminate aggregates and produce primary particles.

As indicated before, most of the blending studies were done using the

in-house-built in-line blender. The basic rationale behind using the static

27
mixing system is that the only power requirement or driving force is that contributed by the positive displacement fuel pump. In a 1-pass mode, no other

mixing motors or devices were employed. This significantly lowers the cost of

operation and maintenance. Preliminary laboratory experiments indicated that

a homogeneous dispersion can be achieved at rather moderate shear conditions.

Review of the static mixer literature indicated that the blending efficiency

is independent of velocity and viscosity constraints and is a function of the

number of static mixer modules. Furthermore, the static mixer can effectively

disperse multi-phase streams of liquids and solids. The literature also indicated numerous applications of static mixer in the chemical, refining, polymer, food and other major processing industries.

3.3.2 Development of the Blending Process

Since very little was known about the slurry and slurry mixing of

AMK, initial experiments; were simple attempts to suspend the slurry mechanically or by hand in the fuel and observe the process of dissolution with time.

The dissolution process was also observed under a laboratory microscope and

the appearance of the solution was compared to that of fully equilibrated AMK

from ICI. The additive was also added in powder form to jet fuel and again

the dissolution process was followed, with time, under a microscope. The additive powder was also passed through a series of sieves and attempts were

made to obtain information about the ?olymer particle size distrioution. It

was found that although 90 percent cd ';e particles fall into the 10 to 9011n

size range, a few relatively large particles (up to 1 mm in diameter) were

present in the powder.

The experiment indicated that on contact with kerosene, the FM-9 additive particles begin to swell. If the dispersion is not rapidly homogenized

in the fuel, the swelling occurs only at the fuel/slurry interface, producing

a coating of translucent swollen polymer gel around the solid phase which

slows the rate of dissolution. The process of swelling of the polymer was

further investigated by casting thin films from solution of the polymer in dichloromethane. The films were then cut into 5 cm long and 0.5 cm wide strips

which were then submerged in kerosene. The swelling of the strips was followed

with time by measuring the strip's dimensions. It was found that the rate of

swelling is very slow, e.g. it took 72 hours for the length of the strip to

double. In a separate attempt to measure the rate of swelling, known amounts

of FM-9 polymer powder were placed in small baskets made from metal cloth (400

mesh); the baskets were submerged in kerosene and the weight gain was measured

with time. In this case the surface of the polymer powder in the basket was

coated with swollen polymer gel and ;indered the diffusion of the jet fuel.

The conclusion from these experiments was that a rapid and homogeneous

dispersion period prior to the particle swelling may help the dissolution

rate. In other words, before the particles start to swell they should first

be separated. Separation of particles and breaking up of agglomerates was attempted first by homogenizing the slurry prior to contact with the kerosene.

It was found that the slurry received from ICI tended to separate, with liquid

ap • ^aring )n the surface and in voids. Homogenizing the slurry reduced liquid

separation and thus was expected to improve reproducibility. This was done

first in a French press ce!l (membrane) disruption device. The press consists

28
simply of a piston operating in a cylinder which vents the macs through a needle valve. The press was run at a total pressure differential of 40,000 psi.

A single pass generated a material which was less gritty than the original

paste. In order to avoid the high pressure, the paste particles were comminuted using a hand-operated homogenizer. This more modest instrument was described as developing a pressure differential of 1000 psi and as capable of reducing particles to 1 micron or less. The homogenizer is available from ChaseLogeman Co, of Hicksville, New York. The paste was sheared as it flowed

through an orifice and out past a closely-fitting ribbed plate. Paste consistency dropped and was markedly srno,)ther after just 1 pass. However, to ensure the maximum particle size reduction (judging from smoothness), the paste

was passed 4 times.

The benefits of homogenizing the paste were tested on the in-line

blending system. Initially the system was tested as a single pass mixing device but produced AMK with unacceptably long equilibration time. Shortening of

the equilibration time was achieved by making a second pass and adding a m niblender to the system.

The static mixer design literature suggested that viscous materials

should be added less than a diameter upstream of the mixer, but attempts to

place the injection port downstream of the pump failed. Excessive back pressure made the injection of the slurry by hand using the syringe impossible. A

mechanical syringe pump which was used next stalled, due to the back pressure.

As Figure 7 indicates, the paste was then successfully injected upstream of the

pump. The slurry did not accumulate in the plumbing and the pump aided the

slurry breakup. The preliminary finding was that one pass through the mixer

for a total of 0.2 sec residence time produced a turbid solution, which progressively developed shear thickening characteristics over approximately half

an hour. The initial results were compared with the results from a proprietary

batch blending procedure developed by ICI which was received by JPL at that

time. However, it was not clear how long the turbid stage lasts, nor the

length of time for full antimisting characteristics to develop by the ICI method.

3.3.3 Optimization of 2-Pass In-Line Blending

The initial first batches of AMK were made in the earlier version

of the blending apparatus which did not have the mini-blender as second mixing

stage. Samples made by a single pass through the blending system produced AMK

which plugged both filter ratio and cup test apparatuses for hours after blending. With the introduction of the second pass, sample characterization became

possible immediately after blending. Filter ratio and cup tests with an occasional fire test (FCTA) were the methods used to characterize the freshly

blended batches of AMK. Next, the time between the two passes was optimized;

the data is shown in Table 9.

The most important

passes through the mixer

the time from the end of

lection in the next pass

between passes increased

period lengthens from 1

finding was that the length

 is an important parameter.

 collection of fluid from one

• Progressive improvement is

• This is seen in the filter

minute (Experiments 2, 4) to

of time between two

This period is defined as

pass to the start of colevident as the time

ratio data, as the

2 minutes (Exp. 6), to

29
`

Table 9. IN-Li-L BLENDING: OPTIMIZATION OF THE TIME BETWEEN TWO PASSES

Experiment Time Between Development Cup Test Filter

Number Passes Time (ml) Ratio

` (min) (hr:min)

2 1 0:02.5 6.5 -

0;11 3.9 -

' 0:19.5 2.6 - 

" 0:30 3.4 - 

0:40 2.9 -

0:50 2.8 -

1:30 2.5 -

;_ 48:00 - 66.2,64.4

4 1 0:30 - plugged

0:40 1.0 

17 0:53 1.0

=

73:00 2.2,2.4 plugged 

6 2-1/4 0:32 2.8 -

^° 0:34 - 59.6

`. 1:03 2.4 55.2

1:34 - 55.8 

24:00 2.3 57.1`

7*4 0:19 - 34.3

0:20 2.8 -

0:30 2.8 -

1:03 2.6 45.6 

j, 1:33 - 43.3

24:00 2.3 51.3

13 5 0:30 - 41.6 

9

0:18 3.1 -

0:22 - 38.2 

0:30 3 ±.5 -

-------------------------------- --- 0:33 - 44.6

No Waring blender second mixing 1:03 2.8 46.8

stage. 1:30 2_7 -

1:36 70.7 

r;

*

Immediately thick and only 24:00 2.4,2.5 51.3

slightly cloudy.

- ** Immediately only slightly cloudy; the best by eye.

Plugged indicates FR > 150

^a

30 

V
the optimum 4 (Exp. 7) to 6 minutes (Exp. 9). Repeated passes did not substitute for the proper time between passes and Experiment 5 (Table 10) demonstrates this.

Table 10. EFFECT OF MULTIPLE PASSES ON IN-LINE BLENDING

Experiment Development Cup Test Filter

Number Time (ml) Ratio

(hr:min)

0:20 - plugged

0:40 5.8 -

0:51 - plugged

0:53 5.4 -

72:00 2.7 plugged

4 passes, one minute apart

No Waring blender seconu mixing stage.

The initial experiments were plagued by problems of sample characterization. Any improvement in that area gave better sample rating. The effect of

homogenizing the slurry is presented in Table 11. The combined data from most

of the experiments done in the blending apparatus up to the addition of the

mini-blender are presented in Figures 8 and 9. In these figures the development of several batches of AMK is followed by cup test in one case and by filter ratio test in the other. It became evident that 4 to 6 minutes is optimum

time between passes. Working the FM-9 slurry by extrusion from the French

press caused the AMK to develop near-equilibrium filter test behavior perhaps

twice as fast as AMK made from unworked slurry. However, this is the result of

a single experiment judged by filter ratio only and is inconclusive FCTA tests

could have confirmed the benefits of slurry extrusion, but as previously indicated, the polymer dissolution initially was followed only by cup and filter

ratio tests. The rest of the extrusion experiments demonstrated that simply

reducing the particle size is insufficient to improve blending.

Two experiments (Table 11), one at the standard 0.3 percent polymer concentration (#12) and one at half that concentration (#14), failed. Extreme

(over 150) though decreasing filter test times were observed and only a partial

reduction in turbidity. Even after three days, the 0.15 percent solution still

plugged the filter screen. It was concluded that the low pressure drop homogenizer design reduced particle sizes but also critically reduced porosity.

With the solvent transport blocked, the particle swelled more slowly and perhaps had the opportunity to form stable gum coats.

One of the important observations was that during the equilibration

period the cup test cannot always distinguish between adequate batches of AMK,

but quickly screens out inadequate development (#4, #5). It is possible for a

sample to have a good cup test but an unacceptable filter ratio (plugged).

Increasing the period between passes from 4 to 6 minutes speeds the material

31
Table 11. EFFECT OF PREWORKING SLURRY ON IN-LINE BLENDING

Experiment Slurry Working Development Cup Test Filter Blending

Number Instrument Time (ml) Ratio Method

(hr:min)

;- 11 French press 0:18 - 37.0

"-^ 0:20 3.4 - 2 passes

0:39 - 54.2 6 min apart

0:40 3,0 - 0.3% AMK

1:08 - 65.4

' 1:10 2.8 -

1:32 - 65.2

1:34 2.6

24:00 2.5 60.9

E

^ 2.5 -

Y- 12 Hand homogenizer 0:06 - plugged 2 passes

4 min apart

0:18 - plugged 0.3% AMK

0:23 3.7 -

r^ 0:29 - plugged

0:33 1.5

1:02 - plugged*

'

14 Hand homogenizer 72:00 plugged 2 passes

5 min apart

0.15% AMK

No Waring blender second mixing stage.

* FR = 195. FR steadily decreased with the development of this sample.

32
M

N atn

g

O 'nV

Z

E

ZWJ

co

KW

LL

a

W

H

^ y

nw

:)Z n ^

z

zW

J

m

W

cn

z

J

1

r

0W

4

1WC

tl

N

J

W

lL

Y

4

z0

Ln

t—J

LnwW

C

NW

H

a

U

co

UJ

L

m

ORIGINAL PAGE 19

OF POOR QUALITY

10 o. 0

N .t a t. d

X

0

^ ^

X X i X

W

i

N

X a

W W H W W^ W p

N

1 I

W

a 1

W

Q 1 1 N

e~e

a

a

a

a X

a

al. a a a Wa

a Z a? a lI °a Iu

Z Z et Z_ N

\

Z_ _Z

0=9) Q

Q^

N `o o N

6GW

I

I

I

I

I 1

I I

i

I

i I

1 I

^'

N

N

N

VI

cA 0

N VD

N

V1

0 yA

N (A

CL 1 1 1 1 6a. 1

L

t J

N N N N N N Lu

q Q D O O x n

W ,L►

Z

q

q 1

N

a 10 in It m N .- O

I W '1S31 df10

33
R

W

_aJ1 } wzawz 0

Il

Z ulJw Z

W Y

J ^

00W

1•

o

uQ 

N

WF

r V)wCF-Nw

H CD Kwn^z

J W L + J

W co

WFZ

rn

urw°

ORIGINAL PAGE IS

OF POOR QUALITY aw

r

11

}G

c

c

10 Q,

j

F- N CL

<`

N

X

o

Lu

•

W

W

Xw 

X

F

w 1

o^

w

i

Q ce

Q

Q

ZQ

ZQ Ln

N

<< 1 Z Z

C,4

Z c41

.- N

V

1

%0 'o

W

1 ! I I II

1 1i

CL

N N

N

N In

~

N (n

NH to

Q

~

Q Q a a

QnQo.Qa

F

N

C

N N

N

N N;H

C

q D

O

O

x

.dCC

r:

Ja
through the plugging stage (the dispersion stage is complete within a second).

Pre-working the slurry seems to speed up the final stage, with a slope after

the filter ratio minimum twice that of the unworked slurry. Experiment 5

demonstrates that it is possible for the apparent viscosity to remain low as

judged by the cup test, while flow through the steel mesh is plugged.

As previously indicated in section 3.3.2, the next approach to improved

blending was to increase the intensity and number of modes of mixing in the 2-

pass in-line setup. Downstream of the static mixer, a commercial Waring blender with a micro volume head was installed. Following the separated recombining plug flow of the static mixer, the fluid experienced a moderate shear

turbulent flow for about 5 seconds. This approach was motivated by the finding that a passable AMK can be made from slurry and Jet A in a single short

period of mixing followed by a 20-minute development. Judging from the filter

ratio, the products are as good or better than AMK produced by the static mixer alone. The results are summarized in Table 12 and all blending runs are 2

passes 5-minutes apart. Additional data not presented in Table 12 can be

found in section 2.2.5 where the above blending procedure was used repeatedly

to produce AMK from different base fuels.

The innroduction of the FCTA fire test to follow AMK development is

shown in experiment #17. The test indicates substantial fire protection 5

minutes after blending. Later tests presented in Table 6 confirmed the data,

but also indicated that full fire protection is obtained in about 90 minutes.

These tests indicated that adequate fire protection is reached well before

filter ratios have equilibrated and that the dissolution end point can not be

established by FCTA. Comparison of the equilibrated filter ratio data for

freshly blended AMK indicates the good reproducibility of the blending procedure, one of the primary objectives of the task. This permitted us to look

into the area of degradability of freshly blended AMK and also the area of

quality control. In addition, it enabled us to evaluate further the reliability of the currently used quality control methods.

The degradability testing was done by producing a batch of AMK in the

blending apparatus, and while the AMK was equilibrating, samples of the fuel

were degraded and tested immediately after. In addition, a recording ammeter

was used to measure the energy consumed in polymer degradation as a function

of time after blending. To degrade the samples we used a Waring blender operating at "high" speed on 500 ml of sample at initial temperature of 20° C for

exactly 1 minute. Energy requirements were calculated assuming constant power

factor and voltage. The results were corrected for no-fluid baseline and are

shown in Table 13. The blending runs were all 2 passes 5 minutes apart. The

initial degradation tests indicated that freshly blended AMK resists mechanical degradation and will require more energy than equilibrated AMK to degrade

to the same level. The filter ratio result confirmed this: less than 50 percent reduction in filter ratio after degradation of a 15-minute sample. The

degradability of two other developing samples of AMK was followed as above but

with filter ratio test only and is presented in Table 10 and Figure 5 (section

2.2.5). Maximum degradability as measured by filter ratio test in these experiments was reached in about 16 hours for freshly blended AMK prepared from

RMH 11118 base fuel. With the same batch, the filter ratio equilibrium was

also reached in 16 hours. As already pointed in section 2.2.5 these results

confirmed the concept that maximum degradability should be reached when the

polymer has reached its dissolution equilibrium in the fuel.

35'
Table 12. IN-LINE BLENDING: EFFECTS OF ADDING THE SECOND MIXING STAGE

Experiment Time Between Waring Blender Jet A Development Filter FCTA

Number Passes Second Stage RMH Time Ratio Fire Test

(min) Number (hr:min) (Set 200)

• 7* 4 off 10608 0:19 34.3 -

1:03 45.9 -

1:33 43.3 -

'

"I

24:00 51.3 -

9* 6.5 off 10608 0:22 38.2 -

0:33 44.6 -

;. 1:03 46.8 -

_ j 24:00 51.3 -

F

122„7 13* 5 off 10608 0:30 41.6 -

15 5 on 10608 0:16 36.3 - 9

72:00 69.5 -

16 5 on 10608 1:00 44.4 -

17 5 on 10608 0:05 - Pass

0:14 23.7 Pass

20 5 on 11214 0:16 23.0

0:30 26.6

0:45 26.8 -

4:00 33.6 -

66:30 38.6 -

d

21** 5 on 11214 0:16 21.3

1:01 27.9

2:33 31.2

70:15 38.7 -

2 Pass Blending. When the Waring blender was on, it was operating during both

F * passes.

Data excerpted from Table 9.

-

**

Data excerpted from Table 14.

i

36
Table 13. IN-LINE BLENDING: RESISTANCE TO MECHANICAL DEGRADATION

OF DEVELOPING AND EQUILIBRATED AMK FUELS

Experiment Waring Blender Development Filter Ratio Relative Degrader Powe

Number Second Stage Time -Before -After -Instantaneous 1 min

(Blending) (hr:min) Degradation Initial Average

13 off 0:05 -- -- 0.51 --

0:15 -- -- 0.59 --

0:30 -- -- 0.79 --

1:00 -- -- 1.09 --

17 on 0:15 23.7 13.9 0.49 0.88

16 on 1;10 44.4 11.2 0.80 0.79

AMK 1-160 - - 36.4 2.22 1.02 1.00

AMK 1-160 - - -- 2.20 0.98 1100

Jet A 10602 - - -- -- 0.67 --

r.

Degrader Power: The wattage in excess of that

empty. Power levels are have

by the degrader power for AMK

Degradation Procedure; Waring blender, high s

Run 13 - 250 ml. Runs

Blending Method: 2 passes, 5 minutes apart.

6I

necessary to run the blender

been normalized by dividing them

1-160.

)eed, 1.5 quart container, 20° C,

16, 17, AMK Fuels - 500 ml.

37
In addition to cup test, filter ratio test, FCTA, and degradability test

(filter ratio) the polymer dissolution was followed by turbidity measurement.

Again, using the in-line blending apparatus, fresh batches of AMK were prepared and allowed to develop with time. While developing, samples were taken

and the turbidity was measured. In some of the experiments, in addition to

the turbidity measurements the development of the fuel was simultaneously followed by filter ratio test and degradability test. Several single-pass inline blending tests were done in order to evaluate again the possibility of

the 1-pass mode. These tests were also used for evaluation of the turbidity

measurements as a quality control tool. This subject is further discussed in

section 3.2.2.4.

The turbidity measurements data is presented in Figure 10, Tables 14 and

15. The degradability tests of developing 1-pass and 2-pass in-line blended

AMKs is presented in Figure 11. The two horizontal straight lines in Figure

11 at filter ratios of 2.7 and 2.9 represent the filter ratios of degraded ICI

samples RMH1-232 and RMH1-177, respectively. These are the levels of degradation to which the developing samples should be approaching if they were fully

equilibrated and degraded by the same method (see section 3.2.2.6).

The turbidity data indicated that the development of freshly blended AMK

can be followed by turbidimetry. Immediately after blending, single-pass material has a much higher turbidity reading than 2-pass material, but it

rapidly falls and reaches a constant level in about 5 to 6 hours. The 2-pass

material which starts with a lower reading also reaches constant level in

about 5 to 6 hours. The final turbidity level—for both is about the same and

they fall in the range of measured turbidity levels for fully developed antimisting fuel received from ICI. If parallel to the turbidity measurement one

does degradability tests, the picture that emerges is quite different. Degradability experiments #21 through #25 presented in Figure 11 clearly indicated that 2-pass material is dissolving faster and approaches maximum

degradability much sooner than 1-pass material. For this particular bass fuel

(RMH 11214) it takes about 10 times as long for the single-pass AMK material

to reach degradability as it does the 2-pass AMK (- 6 hrs vs - 60 hours).

About 6 hours was the shortest time for obtaining maximum degradability in

this type of blending system, polymer and base fuel. The degradability test

also indicated that the correlation of turbidity and degradability of developing AMK is not very good. To some extent, it is the same way for the correlation of degradability and filter ratio for one pass AMK. This is seen in

Experiments #18 and #19 where the filter ratio reaches maximum in 1 to 2

hours, whereas in experiments #22 and #23 the filter ratio of the degraded

samples is between 6 and 7 for a 1-hour sample. More data on the correlation

between these tests can be found in section 3.3.4.

Attempts to shorten the in-line blending equilibration time were made by

further increasing the time between the passes in the 2-pass mode. The inline blending was done the same way as described previously except that the

time between the passes was increased to 8 minutes. The development of the

sample was followed with filter ratio test. FCTA test was done at the end of

the experiment. The results from these tests showed much faster AMK development, with equilibrated filter ratio of about 20 in 2 hours. In addition to

obtaining significantly lower filter ratio, the fuel failed the FCTA fire test

at the 900 setting (see Appendix D). The problems were attributed to degradation of the polymer on the second pass in the in-line blending apparatus.

38
ORIGINAL PAGE 18

OF POOR QUALITY

v

r

N 0

NJ

W

g

^

6

W

gY

4

O

W

Z

W

J

b

W

u Z

c ^

^E Z

w

Z

0

a F,

O

Z ^

w

i--

i w

O

M:

Lo

J W W ^_

Q

W

Y

H

H

m

O FOti

v

L

0)

W
ORIGINAL, PAGE 18

OF POOR QUALITY

L O a a

GI • r M m N h CJ N L 00

4+ ++ a • a o N ri h rl 00 A O. 1-J 'r N r R' N N M M L E .- V W ao•rro Q1 vJ u fY

0

T

Y

a OM NhNhr m O r 1nM a O1N 00 00 .n

rl 1--m 0a N 01 1 n .-i LD Nln Oh In O O hrl lfl N N 13 11 1 1 • 1 I Lim 0) cm 0100 0000

hhLo toM MIn Lo aaa a

FC In

•r v E r 1 n 1 D 1^ x O N 1 O h o O O o. -1 N a O M 1 n O O N o u l

L

E •• 00000.•r rl rl r1N Ma 11100 MO M MO o rIM rl

fn r

I-.0 OOOOOOOOOOOOOrIti rt NN Nln 0100 O V) N M h h h

CL L O N N 'r O tD 00 1D tD 0

rO _' M t O t 0 M x

u- NN N M M

T

0 .-. aNMN o1 x

'b O a)c1 M l ♦: h t D a a M r l O l co

r

1 1 1 N 1~LmOl tD 4'1M LC) Lo 1 to I as L v

7

C

N • r hN W Oln 00001 O OO In 000 E E

r ..

O•--i rIM aO rlN .. .. .. .. .. .. .. ..a

.. OOOMNN .. .. .. .. .. ..

1- L O O O O O N N N N M a a tD h 00 L to lD 00

L O OJ •r tD O O o O 4-J ++

M N a Cl N N

• r of In In In to tD Ll.

5'1

M N h 01 M M h N h M 00 M M N M a I n a^ MMIOx m x C^I^Nx 1n NOp M r1 01 co r10 Ot . 01 Ot

r

1 1 . rlO .

1

rl LL 11'i a N O m co x h h h to tD to In M In In In M tf1 M a a a

Lv NNN Nri

FC

a D 01 00 u'1 00 0 00 0 NNN O O O O O In o 0 0 0 E E E E C 0

C%j N M M M 0 0.-i rl •-•INNMM M V a 0 r•• NM Lo O NM M a00 M O M

.. 1/1

.r ..

1- L

.. .. .; . .; . .. .. .. .. .. .. .. .. .. .. . . .. .. .. .. . . . . ..

0000000000000•--1 •••1 ••^ rl NMa aln t0 O x00 Nb

G

v N a h h J.

C

L O a r• CJ • r O .-• 01 • N 4J 4J U 3

1 0 00 C7 00 C) CJ O •r C 00 Ln tp L 'r N O L1. a ^ O_N

co

0 0

d a U y N w

>1 u C In J.+ 4 + 4J .-. O O O L ^.a

r 00m00mh L UL GJ N o N a J•-• 00011000 NNt d U L C OJ E r W 1 1 •

.

IA 10 O1 • r J..1

0

v

M m M 01 to tp In In In C OJ • r tO -

L L 00 .-1 r1 O O m t L .-

O

c C M C O O O_ 1--' ♦^ C n O i-1 N X

_

b.0 L U• I IC W C a r {J UJ r •r

u•1 O to O m

Ma 00 m Er--0 o.wa N E O.- r i M M O O 6 o u J o L r c= 4) E` .• •. •. •. .• •• '• .. .. .. rn o E W u m E 00000.-i .-1 00a s 0o O 10 .0 E t p M

O M S m to F- •r m

Y

NN

¢

CL.

O

O

Z

N

/n

¢

n.

W

7

6

Z

O

N

F-Z

W

V) /n¢

W

O

I--

C'

W

J-J

H

LL

Z

¢

}

O

mC

H

H

ZW

tY

aY

H

U J

Z W

O ^

U Li

a

N

v

H

40
ORIGINAL PAGE IS

OF POOR QUALITY

V L

a 0) O N r N .- a U

M N •r M t0 O 10 w r 0) Lr Y1 L r 0)o a 0) • r b 1p M M N :3^> 0.N 01 0) W 6' a 0 0 0 N 2

O 0) a U 0

N N O O 0 L r

¢ to a • r L U L 0) 0) 0 N 1 0)a O to 01 t00 010110 M t0 h t0 1n 0101 to a. w U L C4- 0) a • r i-- cr •--I h to M 0) m 01 0) m O 01 h h t0 07 0 td Ot•r N a b ^a u- . . . . . I . . . . . . . . . . . C Ql • r 10 .N >1 C L Lv. hh t0 t0 t0 In V)Ln Ln to LO M to In to t(1 OOML 4.1 0, O 0 r M C N N

F- C C i^ ^ L b

o O Uu

C a r I-t 01 L •r 0

tnO O U) C) a to to In to 0000000 T E.- nN a 01 E e ti N M .1T O M M N 0 C' M O O M O M O C L • r ^ O Y 0E1

MCD U

•E L 0 0 0 0 rl H r-I N M M U') tp to U) IT N a) O tEO r- r E F-.0 hhl^h 0) 0M2m 47 W •r

a a Q L O

a 01 O O O1 a Q) L M 4J •r vv M (u o0 L r i) L O_ J-1 •r 0)• r 10 M N) 0) E r t0 vwW M

a) v•r=n O a N w C

C

4 O N

a t0 h h N h O O h V I 0)a 0 T H . .l0 to 0\ O1 t000 l0ht.O. N W a •r t- .

1 I a Io .O W N N r-1 ti .--t O N t o d' -zr C -:r qr C L L^.. .-1 rIHHHH

O 0117

C

E E O.-1N M[ I to V'h NOC 00 Lo to O

E E C).^ •"'^^ HrIH NO M O tnONtnOH V'

.. .. M .r .. F- L .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 0000000 111 h0.--tN00 •J' L N N c C h h h

v

Cu L ko a 0 O M N O N 10 +I L r}1 O M O • . M H

0) W K

O

4

N a• r N LC) O t N N O N t 0 N 0) O I o M M (n M 1 0) a O H to h M w01 117 V.

c. h t ¢N (D 'a {- . . . . . . . . . .

I 1

a a mau_ vMNN.-•^.-tQlm r^tatntntnu^,v ^raaa e^ C L Lv H H HH.-yH

Fc

01 r H N M •7 t!') hN O OCO tO M V O hN Ntn 0000 E E H.--I rt .-t ti HN N MMa Md- O C) C) x100

r

}- L O O 000000 000 H HN Mtp to (OS N to

t N a h

a

01 L O a Ql • r 1C! 01

L^ h O O A

N O)•r M h l0 V' N QI W O

C a 4^ 0) 1 01 • r— M 01 V'm 1Cn V W N1010 OO MO ct

• E a 00 00 00 C) C) dr 0) M N H m M N of tO 0110 00 0 0 a ro WF t I I

L C Ld W to Oh Cl)mrr 001 00 OD lO to m mf r !t V V a'Lo to 0) O (M N C .j - H H H H

X F

W

G

O) • r E E V h O h O M t C) C O N M C p 01 0 t O c,) C ) 0o 0 0 0 0 0 0 0 O Q .--I H N N N N N M M M d' O NM O M l!') M O M M N O O

1 00000000000 C, C:) M M M tO to -1 .-tN N00^

41

0

0H

¢

K

wWE-J

HW

W

J

t1

N

OWO

aco

w

0

OZ

4

Y

H

OH

mC

N

W

J

d

E¢

O

w

0

C

W N O J Z W

W

W

O Y

f

FZ N W N E 4 wa

^oN 3 ¢ h

E OZ

H ¢ Z

W N C N o: 4 u L U

Z W O Z U O

H

01

b

1'-
^' cn 1^ N V m N p

Duda a3liid

8

W'

J

O

W

_

Y

f

Q

W

W

J

CO

V) W

p J

T z^ H

w

O

H ^

HH

J

H

m

Q

0

Q

CD

C7

W

N

r-1

L_

Of

Lt 

42
Finally, Table 16 presents the data from 2 experiments which were done

to evaluate the influence of higher fuel temperature on the dissolution rate.

The blending procedure was not changed. Only the temperature of the base fuel

was raised to 60° C and the apparatus was used in the single-pass mode. The

development of the fuel was followed by filter ratio test and turbidity. The

data in Table 16 should be compared to that in Table 14 (Exps. #18 and 19).

Both filter ratio and turbidity data indicated much slower dissolution rate

with some filter ratios measuring over 150. The experiment was done twice

with the same results. Due to the limited practical application of this approach, no further work was done.

To obtain a working approximation, blending experiments using FM-9 polymer concentrate in Jet A were performed. The concentrate was prepared by dissolving the slurry in Jet A fuel at polymer concentrations approaching 5 percent. The concentrate was then used for preparing 0.3 percent FM-9 AMK usino

the in-line blending setup. It was found that 5 percent is about the maximum concentration at which one still has a workable liquid. At concentrations higher

than that the viscosity of the liquid was very high and the liquid was difficult to work with. Blending of the concentrate was very rapid and equilibrated filter ratios and turbidity readings were obtained almost instantly after

blending. FCTA test showed adequate fire protection. It was assumed that

this approach has been exhaustively evaluated at ICI and RAE and no further

work was done in this area.

3.3.4 Evaluation and Development of Quality Cont r ol Techniques

Seven quality control tests were examined. These are the filter

ratio test, cup test, orifice pressure drop test, orifice trajectory analysis,

tube trajectory analysis, tube pressure drop test, and nephelometry. The

orifice and tube tests differ only by the length of the exit section on the

device. Since the flow behavior is complex, it was not clear that the two

geometries would result in comparable behavior, therefore they are separated

for reportiny purposes.

The filter ratio test was standard for this work. It is relevant to

both applications areas, namely determining the level of fire suppression and

"s onset after blending and for the second part determining the ease of fuel

degradation to restore flammability. To be rigorous, the concept of the

degradability of AMK relates fluid behavior, under a mechanical input by a

device to complete and stable restoration to near Jet A character for normal

engine use. However, degradability is measured in practice by filter test or

transition velocity behavior, not misting and jet engine combustor behavior.

When interpreting quality control data, it is important to remember this

distinction. Taking the filter ratio test as the operational standard of

degradability and fire suppression ability breaks our development effort into

three general areas. These are: investigation of the filter ratio test,

optimization of the other tests, and verification of the other tests against

the filter ratio test standard. The latter area includes much checking under

conditions where the filter ratio test was found to give improbable results.

Direct testing, i.e., fire tests and degradability measurements, were

primarily used to judge filter ratio test accuracy.

43
Table 16. IN-LINE BLENDING AT HIGH TEMPERATURE (60° C)

Experiment Development Turbidity Filter Bulk

Number Time Ratio Temperature

(hr:min) (FTU) (° C)

26 0:05 20.0 plugged

0:06 19.3

0:09 19.3

0:20 18.3

0:33 17.6 plugged

27 0:05 19.4

0:06 19.3

0:07 19.2

0:12 17.6

0:17 17.4

0:22 15.6

0:23 - 48.5*

0:28 - 31

0:30 15.6

0:37 - plugged`

0:38 15,1

1:01 13,.3 28

1:12 - plugged*

1:23 12.5

i:40 11.3

2:00 10.5

3:00 9.4

4:00 8.8

5:00 8.3

24:00 6.7 105 22

48:00 6.0

72:00 5.5 143

Blending method: JPL in-line blender, 1 pass, Waring blender second stage,

64° C feed, 55° C output. The 1 kg of material was allowed

to cool by natural convection in air.

The first three filter test samples were cooled (20° C bath) for about 10

minutes immediately before analysis to lower their temperatures to the 20° C

standard,

44
The quality control development work may also be classified by sample

type, which is to say, area of application. Nephelometry and the cup test

were only used with developing AMK fuels, since this is the most likely application. The pressure drop, :and throw (trajectory analysis) tests, however,

apply to various degrees, to both areas. In addition, digital image processing has been integrated into a new technique for measurement of degraded

and undegraded fuel spray characteristics. This test method is described in

detail -in Reference 14.

3.3.4.1 Filter Ratio Test, Cup Test, Nephelometry, FCTA

The first quality control method considered is nephelometry. It

will be characterized in terms of its matchup with filter ratio and

degradability.

Eight turbidity vs. time runs are plotted in Figure 10. There are five

1-pass in-line blended batches, indicated by the triangular symbols, and three

runs at the standard blending procedu re of two passes, 5 minutes apart. The

1-pass and 2-pass envelopes converge ai. an hour and a half, and equilibrium

(non-changing) turbidity values are ,,^Isached at 6 aaurs.

The turbidities of developir,g samples track filter ratio in general.

Both illustrate asymptotic behavior with rates of change that remain in

proportion as the samples develop. See Tables 14, 16, and 17 and Figure 12.

During the first few minutes, however, there are differences. Turbidities

always decrease in time, even at short development times of 4 and 5 minutes.

Filter ratios, however, are rising at the quarter hour mark from some minimum

value, which is a reversal of the initial rapid decline in filter ratio whose

presence is inferred since devel-ding AMK is no doubt plugging immediately

after blending. Runts 18 and 19, with only one blend pass, are poor quality

blends and show extended initial plugging behavior, with the filter ratio

minimum of one run shifted to the 40-minute mark. Note that the turbidity did

not point out this anomaly. Also,.though a log-log plot of turbidity against

filter ratio shows that the rates of change are fixed for any one blend batch,

the slope varies from batch to batch. First (#21) through fourth power (#19)

relationships are observed. One consequence is that equilibrated filter

ratios and turbidities cannot be predicted from initial values.

Table 16 presents two batches blended at 60°C, which resulted in extreme

plugging of the filter test apparatus. Yet the turbidity at 1 hour is the

same as for a FR=87 sample of properly blended batch (#18 Table 14).

A second way to understand turbidity measurements is to correlate them

with degradability, as presented in Tables 15 and 18, and Figures 10, 11 and

13. Four batches of AMK were blended and characterized by simultaneous turbidity and degraded sample filter ratio test measurements.

The reference for the degradability of AMK fuels in this study is the

behavior of ICI blended AMK fuels 160, 177, and 232 under the standard degradation procedure. The procedure specifies that 300 ml of fuel at 22° C is

degraded in a Hamilton Beach Scovill Blender at the highest speed for 30

seconds. All three reference fuels have a degraded sample filter ratio of

45
15.6

9.8*

7.8*

10.3

7.8*

6.4

5.1*

4.9*

10.5*

8.7*

7.5*

5.1*

4.9

7.6*

5.5

4.7

4.2

Table 17. CORRELATION OF TURBIDITY AND FILTER RATIO OF AMK FUELS

Sample Development Filter Turbidity

Time Ratio (FTU)

(hr:min)

DEVELOPING AMK FUELS

18 0:15 87

0:38 58.1

1:05 63.9

19 0:15 52.6

0:32 54.0

1:01 59.0

4:00 62.0

72:00 62.0

20 0:16 23.0

0:30 26.6

0:45 26.8

4:00 33.6

66:30 38.6

21 0:16 21.3

1:01 27.9

2:30 31.2

70:15 38.7

FULLY DEVELOPED ICI AMK FUELS

RMH1 - 160 25.2

RMH1 - 177 49.7

RMH1 - 232 30.5

RMHI - 233 27.8

* Interpolated data

**Very temperature sensitive

All data in this table were measured at 22° C.

The Developing AMK data were excerpted from Table 14.

6.7*

7.6

4.1

11.0**

46
10

0

m

D

0

1 n+'

ORIGINAL PAGE IS

OF POOR QUALITY

v

O 2 PASS EXPERIMENT 20

O 2 PASS #21

V 1 PASS 018

C. 1 PASS f19

+, H ICI AMKs RMH 1-160, 177, 232

10 20 30 40 50 60 70 80 90 100

FILTER RATIO

Figure 12. CORRELATION OF TURBIDITY AND FILTER RATIO OF IN-LINE

BLENDED AMK FUELS.

47
Table 18. CORRELATION OF UNDEGRADED SAMPLE TURBIDITY AND QEGRADED SAMPLE

FILTER RATIO OF AMK FUELS

Degraded Undegraded

Sample Time Sample Sample

(hr:min) Filter Turbidity

gatio (FTU) g9^

DEVELOPING AMK FUELS

22 :32 7.7 9.10

1:00 6.05 6.751

6:00 4.89 4.661

23 0:30 10.3 8.20

1:33 7.15 5.551

6:12 5.07 4.501

72:00 3.26 4.53

24 70:30 3.452 4.72

25 0:30 6.3 6.79

1:34 3.62 6.051

6:00 3.05 5.87

70:00 2.62 5.771

21 70:15 2.84 4.25

ICI AMK FUELS

MK RMHI-160 2.863 6.72 i

AMK RMH1-177 2.875 7.64

AMK RMH1-232 2.726 4.15

AMK RMH1-233 4.6-12

Jet A 0.87

Interpolated DEGRADATION PROCEDURE

2 Average: 3.40, 3.49

3 Average: 2.84, 2.88, 2.85 300 ml

4 Average: 6.55, 6.68, 6.94 30 seconds

5 Average: 2.79, 2.96 Hamilton Beach Scovill Blender

6 Average: 2.70, 2.74 Highest Speed (Liquefy)

5 cup (1.25 1) container

22° C

The Developing AMK data were excerpted form Tabie 15.

48
2.72 to 2.87, despite relatively larger -variations in filter ratio (25.2 to

49.7) and turbidity (4.15 to 7.64). This is an indication that the degradation procedure might be used as a quality control test.

Figure 11 presents the degradability of the blend batches as a function

of time. Only one experiment with 2-pass blending, #25, was followed during

its entire development. Its curve reaches an equilibrium level at about 6

hours. The three-day sample falls, in the band for fully developed AMY., a

position corroborated by experiment 21 (for which only the final degradability

is available). The two single-pass blending experiments, 422 and 23, reach

the same level, but not for about 5 112 days. A third 1-pass experiment, H24,

confirms that 1-pass material is not quite fully degradable at the three-day

mark.

Figure 13 presents a time-independent plot of turbidity against degradability. There is a near-linear relationship between the two for most of the

development, but the relationship fails completely at the point where degradability reaches a filter ratio of 5. It is also significant that the new ICI

AMK, RMH 1-232, with an age of two months, correlates with the three JPL

blended batches, but the year old ICI AMK does not. Variations in age, water

content, and base fuel turbidity are possibly factors explaining the-difference.

Figures 14, 15 and 16 make use of the mass of DC-10 fuel simulator data

to indicate the relationship between cup and filter ratio test results and

FCTA calorimeter and thermocouple fire tests. This is the only report of

calorimeter fire test data, as this sensor is harder to use than the rapid

response thermoucouple. The solid circles are the results of samples degraded

in a blender. The open circles are the results of DC-10 Fuel Simulator sample

firings. Each point is the mean of several determinations scattered with a

standard deviation of 10 'to 20 percent. The.calorimeter was HYCAL C-1300-A-05-072

and was positioned 9 incites downsteam of the nozzle exit, 20 inches off axis.

The thermocouple was placed on axis 10 inches from the nozzle. Samples degraded by fuel management system equipment tend to have higher flammabilities

than blender degraded samples with the same cup or filter ratio test. This

fact could be important in setting acceptable filter ratio limits. For

undegraded fuel, cup tests of less than 3.5 ml will result in a FCTA test

pass, with a temperature rise less than 10 percent of that of Jet A. Most often

samples with filter ratios greater than.17, will pass ( less than 17 percent that

of Jet A or about 75° N and below FR =7, they, will faii. The calorimeter correlation is slightly better than that obtained with the thermocouple.

A thoroughly unexpected resul't'is the collapse of fire protection when

AMK i5 diluted with relatively small quantities of Jet A. Table 19 and Figures 17 and 18 present the data. The effect does not depend on mere dilution

by Jet A, but on whether or not the diluting material contains glycol. This

was shown for filter ratio test only by Timby (reference 15). The cup test

and filter ratio test data are both misleading. Table 19 demonstrates the

effect on the cup, filter ratio, and fire tests of the addition of two diluents: thoroughly degraded (FR=1.4) AMK and Jet A. As the fraction of degraded AMK diluent rises there is, a, gradual increase of flame temperature, but

even at 40% diluent the mixture still passes. The flammability of jet fuel

was never reached. The filter ratio shows the expected gradual decrease.

However when Jet A is added, the filter ratio, inereases, eventually exceeding

49
W

Z

U

Qm

Y

0

Z

", A N H N Y °a^a^QI

Q q 4 U +

0

—I(

P

ORIGINAL PAGE 19

OF POOR QUALITY

-^•

wzH

J

I

Z

H

C)

O

rH

J

ca

H

Q

IL Q

cm

cm

Y w

C]

^ Q Z

W G

QQ Y

OC ~

0 0

W H

^ D]

Z

D F= J

W

w

O o w

oX: H Q

p^ m ¢oJ W

a cc

wwO J w o]

M

In L

7

p1

LL

M

O P m n v Wa v •• ..

)IWV a3aVS03a Ao 0I1VS S3111A

50
4: 

t:; 

~ 

'" '<i ..... ~ 

1.0. 

o DC-10 SIMULATOR SAMPLES 

• BLENDER DEGRADED AMI( 

O.al 

O.6~ 

oJ 

00

0 

8 

0 

0.21- 0 

0 

0 0 0 

0 0 

00 0 0 co 

0 0 0 0 0 

0 0 

0 0 0 

I d- oL--ocm I 0 

2 3 4 5 6 7 

CUP VOLUME, nil 

Figure 14. CORRELATION OF CUP TEST AND FCTA THERMOCOUPLE DATA FOR 

SYSTEM SIMULATOR AND BLENDER DEGRADED SAMPLES. 
<I: 

0-

W 

t11 

.., 

l- N 

~ 

~ 

----~-~-,.~------

I.O~I-----------r----------'-----------~----------~----------r-------

0.8, 

I 

0.6 

0.4 

0.2 

o 

o 

o 

o DC-l0 SIMULAT

• 0 

• BLENDER DEGRA

0 0 0 0 

~ 0 

5 

o 

00 

o 

10 

o 

0

0 

o 

o 

o 

o 0 

o 

a 

..L 

15 

o 

o 

a 

FILTER RATIO 

o 

a a 

a ~ 

a a <b a a£, a 

.1 1 

20 25 

Figure 15. CORRELATION OF FILTER TEST AND FCTA THERMOCOUPLE DATA FOR DC

FUEL SYSTEM SIMULATOR AND BLENDER DEGRADED SAMPLES. 
ORIGINAL PAGE IS

0O

OF POOR QUALITY

cC9

O 0

0

i

0

8

zo

O LL

0 .

8o ^ W

g uia W S

0

0 wh

O CW

O O

F4g U

0

cD

0 ao

Q

U x

0 oe LL W

Q

00 W z W

0 -^ m

0 0 LL

O

ra

cz

0 0 JGu-i J

LL O

X: 0

LL

O N

O O O W

0 00 a > J n W

0 O

K J

0' W

O

0

ULL

R

v h ti

N

O L.

61

LL

LMW

QQ^ ^

v5

Q

0

0 Q

O

o

^ W

O_ O

^ W

CO

O ^

O co .O ry O

O O O O

V 13fe/a 

N313WIaOlb^ 

53
100. A mixture of 17 percent Jet A in AMK is already reduced to a marginal

pass. This radiometer and thermocouple fire test data are plotted as a function

of the mixture in Figure 18. The cup flow increases with dilution, indicating

progressive weakening fire protection as expected. However, Figure 17 shows

that Jet A diluted samples have an immediate increase in flammability with an

increase in cup test volume. In contrast, degraded samples must reach a cup

test of 7 before a flammability rise is seen. Put another way, the figure

i demonstrates that the fire protection of Jet A diluted AMK is much less than

the fire protection of degraded AMK at any given cup test value.

Table 19. EFFECT OF DILUTION OF AMK ON FIRE SUPPRESSION AND CUP

AND FILTER RATIO TESTS

% Diluent Polymer Cup Test Filter FCTA Fire Test

in Undegraded Loading (ml) Ratio Rise AT ARAD***

AMK (wt. %) (° C) eTJet A* ARADJet A

Diluent: FR 1.4 Degraded AMK

0 f - 38 46ass 0.12

20 0.' = 42.5 46 pass 0.12

40 0.30 25.4 70 pass 0.18

60 0.30 - 27.0 231 fail O.f1 -

80 0.30 - 23.2 273 fail 0.71 -

Diluent: Jet A

r 0 0.30 2.8 33 ±1 - pass 0.027 ± .01 ** -

17 0.25 3.3 38 ±5 pass 0.16 ±.03 0.045

33 0.20 4.0 38.5 ±1

_

fail 0.5 -.1 * 0.3 ±.1

67 0.10 6.9 80 ±13 - fail 1.1 *-.1 1.0 ±.2

83 0.05 7.5 >100 - fail 1.1 ±.1 1.0 ±.2

*Jet A FCTA temperature rise 386° C ***Radiometer data

**FCTA fuel speed 250

Work previously reported by JPL also indicated that AMK has the tendency

to form a stable transparent gel when it is sheared at low temperature. We

anticipated that the quality control methods for AMK including the filter

ratio test might be influenced by the temperature history of the fuel. In

addition, Pratt & Whitney (reference, 12) recently reported very high filter

ratios for AMK after exposure to temperature below 0° C.

Samples of AMK first were exposed to moderate shear such as may occur

when the fuel is passed through aircraft booster pumps and then attempts were

mace to degrade the fuel. It was found that one pass through the JPL in-line

blending apparatus produces AMK with a filter ratio of 12 to 15, which is

close to the filter ratio produced by passing AMK once through boost pumps

as reported by McDonnell Douglas (reference 13). These pumping and degradation results are arranged in Table 20 to show their effects on quality control

tests. In the first three pairs of experiments, the filter ratio is increased, from 12 to over 100, from 3 to 50, and from 9.5 to over 100, by lowering

54
P

NW

m JO

F-NW

F-aUwOZ0

I-QJw

ce00U

E O

z I—

h^

win

^ w

C3 C U w r

C:) w

Z U

w w LWi H

z^

n 'yv

rn

•rw

ORIGINAL PAGE IS OF POOR QUALITY

G

o O 00' O—

O

O

O 00

0 cn

0 00

0

0

0

O

O

O0

O

O

H

8

Y

a

Y

O

Q

Qw

LUO

O

O0

0

J0

E

0

O J_ KW

C 

c

N

o

Q ld

w

O

{—

LU Q m

1,

OY

Oo

n

•

O°

O I 1 I p

4

N

O

W

dYN

O

v 13riv/lv
UKiGiNAL PAGE 19

OF POOR QUALITY

2

O THERMOCOUPLE

O RADIOMETER

FCTA

SPEED CONTROL: 2

gAIR PRESSURE: 95 psi

0.5

a

t

4

4

0.1

0.0.5

0.02

0 0.10 0.20 0.30

FM-9, % WT

I I I I I

100 67 33 0

% JET A IN MIXED AMK

Figure 18. EFFECT OF DILUTION WITH JET A ON AMK FLAMMABILITY.

the temperature in otherwise identical tests. This increase is partly justified by the fire test results, which indicate enhanced resistance to degradation at low temperature. In the second pair, the 200 speed FCTA temperature

rise is halved by lowering the temperature, and at -40° C, there is only a 50°

rise at speed 900, better than even the undegraded AMK rise of 100° C. The

filter ratio increase is to some extent temporary, as found in the retested

filter ratio after a wait of one to four days. This effect varies from lot to

lot. The apparent filter ratio of AMK 172 is not reduced by 15 seconds in the

blender at -20° C, whereas AMK 231 shows a two-fold reduction. Yet the fire

test behavior of these two samples is not significantly different. Additional

experimentation shows that heat treatment (60° C) somewhat reduces the filter

ratio of low temperature degraded samples. This is an indication that the low

I

56
ORIGINAL PAGE 15

OF POOR QUALITY LOA N

rl .-1

O O O et M M

0O

LA

O

O 0i r N rl

iz

L^

N

N O rt OtiA

O

M O

LA

n

'-1

N N I

^^ 1 N •--1

57

L L

N U1

C C

N N

m m

U U

N N N VI

N N

O O 00 Lp M Cl)

Ln

O OO

•-L A

O O

N tr1 a

0

CD a

N N

•r

Y L

ro

a

N O

Ln O • L N

o O

00N

i0

d T

Y •r

N L0

U O

O O1

O C N • r ••

Y N

YIO C7 •--I N r-1

Y d

to Y Y

y ro Y 3

010

Y

roL

w N m

7 U)

r W •p d♦< Y. roX

'vC

Old

9. 4NdNOO

lT

O O O O N N N N 1

LJ

L

L

C1

N

N C N C U G) V N • r r r

Cm aca

Y U Y U N N

N !A N N N) N

ro lA ro to d. r-y d M

ri N ri N ^ 7

[1d

00W

MM

NN

n ;1 N N

O O

N N

W co M M

N N1

NN

OVi N

M •--1

N N 1 1

L Ca) N

m m

N W

lA lA

N •--L

W L1p

M N

N 

N

t` M

rl N

N N U U

C C

Y Y

N ^ N N

ro ro

^. d

H N

NoL v

tt U

H*

d . 1 C) F Y O U N

lL

FLnW

Ew

41

K Y L FJ N Y O

J Y r Y

N • r ro W LL LY

WSF4- N O V E A _ O

N F-^

CDQO O d d •r ^ O L1 Y r E C7 ro N C o ba L •r W a) p L

E Y f- E < ^ W ^-+ 4 WaSW C N

1- O L 3 4J

C) ro ro U

J a L W L CL—

CD rn E H cz F^ UW

LL

ILW

COY

CD rov N O

4) L f

.Db p61L

C O

r })

r ro lL p,'

L

G) Y S d

d tY ^Z

t\ lA

LV
ORIGINAL PAGE IS

OF POOR QUALITY

temperature shear causes excessive entanglement of the molecules, rather than

additional covalent crosslinking, and explains the deviation of filter ratio

test values without a corresponding divergence fire protection behavior.

3.3.4.2 Pressure Drop and Trajectory Analysis

Figure 19 illustrates the shear thickening behavior characteristic of fully developed AMK. When flow rate, increases from 6 to 7 units

(dimensionless flowrate), there is a tripling of the resistance to flow. This

at,rupt transition is called the critical transition. Under the conditions of

0

7

UJ

6

^J

J

V.

cm 5 N

W

.J

Z

O

N

Z

w 4

f

0

3

2

1

22 GAUGE, 55 mm NEEDLE,

0.71 mm ID, VD = 70

1critical - 9200 s

-1

AMK: RMH 1-160 AT 2&C

0 1 2 3

PRESSURE DROP ACROSS EXIT SECTION, psi

Figure 19. PRESSURE DROP OF AMK FLOWING THROUGH AN ORIFICE SHOWI14G THE

CRITICAL SHEAR RATE TRANSITION.

58
this figure, flow through a 0.7 mm ID tube with a L/D (length to diameter

ratio) of 70 at 20° C, t critical is 9200 inverse seconds. Peng and Landel

(reference 11), measured a value of 3000 s- 1 for this 0.3% polymer solution.

The oscillations at the supercritical flow rate are not characteristic of the

material, but rather of the fact that the syringe pump would stall, allowing

the material to relax and pressure to fall, which allowed flow to resume to

start the cycle over. The syringe pump was used only to generate part of the

Table 21 orifice pressure drop data. The FCTA pump, which did not have significant backpressure problems, was used for the remainder of the work.

Table 22 presents the effect of the exit length on the sensitivity of

the pressure drop and trajectory analysis tests. A 152 mm tube and a 371 mm

tube of the same 3.15 mm diameter were used, giving L/D ratios of 48 and 118.

There is a significant negative effect of increasing the length on the throw,

i.e., trajectory tests. The onset of throw shortenin is about the same for

both tubes, at pump speed 200, and the rate of c ange of the difference between Jet A and AMK levels off at similar levels of 450 and 500. Huwever, the

magnitude of the deviation at 450 is 4.8 inches for the short tube, but only

2.3 inches for the long tube, and the same behavior is found at the upper

speed limit, 8 inches as opposed to 4 inches of shortening. The Jet A throw

length is virtually the same for either tube.

The pressure drop test also is better with the short tube, but only

slightly. The onset of rapid pressure rise is at speed 300 for the short, and

350 for the long tube. Both reach a maximum AMK-to-Jet A pressure drop ratio

of three and a half at speed 500. Both AP ratios tail off to 2.5 at maximum

speed 1000. The AP ratio is in general a little higher with the short tube.

A comment is in order over the choice of absolute differences to compare

AMK samples with Jet A for the trajectory test while ratioing AMK and Jet A

pressure drops. Some ICI AMK fuels (also see Table 23) have a plateau region

where the throw remains constant despite increasing flow rate and thereafter

the difference between the sample and AMK throws varies only slightly with

flow rate. An absolute magnitude difference conveys more information in this

case. The gap between AMK sample and Jet A pressure drop shows no such

behavior. Also, fluid pressure drop scales with diameter and tube length

according to well known laws. Ratios between APs of two different fluids are

transferrable between one geometry and the next. The Jet A pressure drop

normalized pressure ratio is thus the statistic of choice in this case.

We turn to the effect of tube diameter having concluded that a tube of

L/D = 48 is bettee than a longer tube. Three tubes, 0.84, 1.37 and 3.15 mm in

diameter and with L/D restricted to 48 to 60, are compared in Table 24. Figure 20 graphs the pressure drop data, and Figure 21 the trajectory data, of

Table 24. Since the FCTA pump only has a sixfold flowrate range of 4.37 to

26.4 ml/sec, there is unfortunately a corresponding change in i range with

diameter. Shear rate varies as VD- 1 or as inverse diameter cubed, where V is

the mean flow viscosity. Throughout this report diameter changes are linked

to Y changes. The only exception is found in Table 21, where the syringe pump

driver provided a lower flow rate, and thus f, range.

The product throw times area is the volumetric flow rate. Thus the

product throw-diameter squared is independent of diameter and shear rate for

59
Pressure Drop Apparent Viscosity

Range Range

eP/y

Flowrate y high low high low

Sample (ml/min r1 (psi) ( psi ) (poise) (poise)

0.54 mm Orifice*

K

RMH 1-160,

FR 36.5 0.33 356 0.02 --- 3.20 ---

1.25 1350 0.04 --- 2.22 ---

2.31 2490 1.16 0.68 32.1 18.8

2.46 2650 0.99 0.52 25.8 13.5

1.20 1295 0.14 0.12 7.45 6.39

1.23 1325 0.16 0.14 8.33 7.29

1.94 2090 0.40 0.25 13.2 8.25

2.08 2240 0.42 0.24 12.9 7.39

2.23 2405 0.51 0.27 14.6 7.74

2.30 2480 1.59 0.59 44.2 16.4

2.39 2575 1.88 0.72 50.3 19.3

Degraded

AMK

FR 27.8,

Cup 3.13 ml

1.23

1.37

1.66

1.94

2.01

2.08

1325

1475

1790

2090

2165

2240

0.23 0.17

0.23 0.17

0.36 0.23

0.41 0.28

1.24 0.51

1.95 0.85

12.1

10.8

13.9

13.5

39.5

60.0

8.6

8.0

8.9

9.2

16.2

26.2

Degraded

AMK

FR 22.2,

Cup 3.67 ml

0.62

0.92

1.23

1.80

2.08

2.29

2.37

1.94

2.43

2.51

2.58

670

990

1325

1940

2240

2470

2555

2090

2620

2705

2780

0.02 ---

0.04 ---

0.06 ---

0.31 0.23

0.43 0.29

0.47 0.27

0.56 0.34

0.43 0.33

0.86 0.57

1.68 1.23

1.79 0.76

2.57

2.58

3.17

11.0

13.2

13.1

15.1

14.2

22.6

42.8

44.4

---

---

---

8.2

8.9

7.5

9.2

10.9

15.0

31.4

18.8

^ ...

Table 21. DETERMINATION OF EXTENT OF DEGRADATION BY ORIFICE PRESSURE

DROP (page one of three)
ORIt mm 

PAO, 6^ OF POOR 

QUAL11IS

Table 21. DETERMINATION OF EXTENT OF DEGRADATION BY ORIFICE PRESSSUP,E

DROP (page two of three)

Pressure Drop Apparent Viscosity

Range Range

4P/y

Flowrate y high low high low

Sample (ml/min) (s- 1 ) si) (psi) (poise) (poise)

Degraded AMK, 0.38 410 0.01 ---- 1.0 ---

FR 16.9, 1.17 1260 0.02 ---- 1.3 ---

Cup 4.62 ml 1.77 1910 0.06 0.05 2.2 1.9

2.15 2320 0.16 0.12 4.6 3.5

2.44 2630 0.29 0.24 7.6 6.3

2.67 2880 0.39 0.31 9.3 7.4

3.11 3350 0.48 0.37 9.9 7.6

2.67 2880 0.26 0.19 6.2 4.5

3.26 3515 0.46 0.34 9.0 6.7

3.78 4075 0.83 0.53 14.0 9.0

3.93 4235 1.07 0.73 17.4 11.9

2.67 2880 0.29 0.22 6.9 5.3

4.16 4485 1.46 0.75 22.4 11.5

4.46 4810 1.47 0.66 21.1 9.5

Degraded 0.38 410 0.00 --- 0.0 ---

AMK, 1.17 1260 0.00 --- 0.2 ---

FR 11.3, 2.67 2880 0.07 0.03 1.8 0.8

Cup 6.5 ml

0.712 mm Orifice*

Degraded 1.3 610 0.00 --- 0.5 ---

AMK, 10.5 4935 0.05 0.05 0.7 0.6

FR 11.3, 13.0 6110 0.23 0.20 2.6 2.2

Cup 6.5 ml 15.5 7285 0.51 0.41 4.8 3.8

18.0 8460 0.73 0.55 6.0 4.5

20.5 9635 1.03 0.80 7.4 5.7

23.0 10810 1.34 1.07 8.5 6.8

25.5 11990 1.28 0.91 7.4 5.2

61
r

ORIGINAL PAGE 15

OF POOR QUALITY

Table 21. DETERMINATION OF EXTENT OF DEGRADATION BY ORIFICE PRESSSURE

DROP (page three of three)

5T '

Pressure Drop Apparent Viscosity

Range Range

oP/ Y

Flowrate y high low high low

Sample (ml/min (s- 1 ) (psi) ( p si) (poise) (poise)

1.31 mm Orifice

AMK

RMH 1-160

(14° C) 4.37 20,010 4.88 16.8

6.10 27,920 7.74 19.1

8.25 37,790 11.8", 21.6

10.48 48,000 15.2 21.8

DC-10 Fuel 4.37 20,010 1.44 4.96

Simulator 6.10 27,920 3.29 8.13

Sample 8.25 37,790 5.85 10.7

3.9.3.3(4) 10.48 48,000 9.02 13.0

Engine Intake 12.50 57,250 13.14 15.8

AMK, Top of 14.65 67,100 17.45 17.9

Climb 2/14/82 am,

Filter Ratio 6.0

Jet A (15° C) 4.37 20,010 0.94 3.24

6.10 27,920 2.11 5.21

8.25 37,790 3.95 7.21

10.48 48,000 6.42 9.22

12.50 57,250 9.05 10.9

14.65 67,100 12.8 13.1

16.8 76,940 16.4 14.7

*Syringe pump as fuel driver

**FCTA pump as fuel driver

***N,.e change of units from per minute to per second with change of fuel

driver.

Note. The high and low values of pressure drop and apparent viscosity are the

extremes of the oscillations observed.

62
W

O!NNWdWY

F-WO}

F-H7HNzWNW2

F- Ln

Z Ln

O W

F2

F- N C=-M H

Zm

w}

J JQ Z Z

O Q

I— Y

U R

W O

Lo FF- W

X Q

W a'

F^

W

O O U

W 

W O

L L. z

W o NNd

.nm

FORIGINAL PAGE 19

OF POOR QUALITY

0 "M .H 00 N cD 00

^ Ma+n W 00OtiNUnn n

4

m 00000.-+r•.+•-1N4

r N

(u

E

7EW IzrM NOS N OOS in 

CL

C

H 

NM

Nm V U1 to 'O n OS U)

MM

ll'1 Ln 0 0 0 0 0 0 O 7 0 H 

N

O

r

L

(v

E

O N

E M L 1^ mer O Ln N N a

N M

N

to N

n OOOO'r NN V V I^OS

d

M

L ^

G.

L U7 M'O MMONr mwN

Q

Y N M Un m m N C to OOOO N.--I NN MKf L7 .--L J0 E

U

d

6

M ^M to t0 to to

FN b ti tO O tr; rl:

O

L w Nw w m U7 N N N N N N M d' N

^

N

N

to to lb U) M M 

mV

N 'O rl L)0"4;l nOm0

C Ln r1 r-1N NNc.'N mM V' .-1

ti

tI

N

3O

EEE

m OU) W W m

m MLoM

r

F--

N r1 'O N L1') OS .-1 m U) ' p W M H M .-L .-• .•1 N N N N N M N Mm I 1 + I E Y E to 00 m m to 00 In Ln

U

QN tp rt U')Ol H Hr1 N

C 00* ) m m

o

t o

rl.- L N N N N N N M m r l

r1

+N

tr In o Ln Ln Ill to to L O1!') 2J

^y NOO O.-+

V n. N nOt\ O •r1 vaiIo-v X0 .4- 'O to ti'.NMmct ^t atn^ao

._, u4-0

G.N 0 0 0 0 Cl 0 0 0 0 0 0

E

0-

O N(Sm m V V ttnn'O00O00 F1 N r

Qj

4- , n O m 00 m u't L

m .•r N R ^h U)'O'O OO 00'r

\

3i— d'tON c; cZ 

m4 rl t0 O E .-I •-L .H r• .-+ r-1 N N rW

E

co to

00 .,M

EE L

E •YQ N, E

L11 ^ 10d

O D^

J J F63
ORIGINAL PAGE IS,

OF POOR QUALITY

Table 23. DISCRIMINATION OF EQUILIBRATED AMK FUELS BY THE TUBE PRESSURE DROP

AND TRAJECTORY ANALYSIS TESTS

Flowrate Pump y AMK AMK AMK AMK AMK AMK* Jet A

ml/s) Speed (s- 1 ) 233 232 232 205 177 160

Throw (inches)

4.37 000 1425 6.8 6.5 6.5 - 6.5 6.5 6.3

6.10 100 1985 11.3 11 11 11 11 11.3 11

8.25 200 2690 15.5 15 15 15 14.3 16 16

9.37 250 3055 i-.8 - 17 - - - 18

10.48 300 3415 11.5 - 19 11.5 11 19.5 19.5

11.49 350 3745 10.5 - 20 - - 20.8 22.8

12.50 400 4075 11.3 20 20 11 12.5 20.5 24

13.6 450 4425 12.8 - 21 - - 20.3 26.3

14.65 500 4775 14.8 - 22 - - 21 27

16.8 600 5475 18.5 24 24.5 18 19 23 29

21.8 800 7100 27.8 28 30 - 27 29.5 38

26.4 1000 8605 36 36 -38 - 35.5 38.5 47

Filter Ratio

Fire Test (° C)

Speed 200

Speed 900

Jet A Ref (200)

27.8

20

140

-450

30.5 30.5

20

145

-450

33.3 49.7

20

110

-450

25.2

15

85

-290

Pressure Drop (psi)

4.37 000 1425 0.25 0.20 0.26 - 0.24 0.22* 0.24

6.10 100 1985 0.38 0.28 0.36 0.37 0.35 0.32 0.34

8.25 200 2690 0.52 0.69 0.50 0.56 0.63 0.40 0.34

9.37 250 3055 1.05 - 0.57 - - - 0.49

10.48 300 3415 1.82 0.79 0.79 1.70 1.75 0.68 0.49

11.49 350 3745 2.53 - 1.25 - - 1.21 0.62

12.50 400 4075 3.06 1.87 1.73 2.97 2.71 1.64 0.59

13.6 450 4425 3.54 - 2.09 - - 2,14 0.74

14.65 500 4775 4.07 - 2.35 - - 2.51 0.89

16.8 600 5475 5.03 3.30 3.08 4.72 4.11 3.39 1.00

21.8 800 7100 5.95 4.56 4.40 - 5.71 5.01 1.51

26.4 1000 8605 7.66 5.52 5.68 - 7.14 6.25 1.87

Exit Section: 0.124" ID x 6" tube (3.15 mm ID x 152 mm)

*AMK 160 data are excerpted from Table 29.

64
L C W O Y •^Y

U

^ a

O

rO x%

Y yOy

W E 9 N C N a

oawtO Y

O

a"

9 N

oJ.EE

N U1

Y N

J ~

v000

aV

t y 1- a

N

N r• L a O J

QYJ Y•

E YN

.^ n

E9

v J

^ N .v d J L

va

L y

adl w a

to d

9

a

a ar.^ l•i J N Y

a CI

avn

m d 1E^

T •Y IS ^ V L n 4• a

++ Oa L

JAY E ny L l

a J u

a N d

N L O •^ n LN T d

L Y

o aa

C N 4

2 d O N N L •^ a ttr

M ^ M M 4

ORIGINAL PAGE

OF POOR QUALI'

_o a

^ M Y

a R N

O

L ^n

K ° E .h•1

^

L b I

W N N

ui

^^ LSO h n N N v ¢a[

^ N y4

e a N mE lm

^ a

O 6

T Y

H ^

1--1 n ^ r 1--1 n

In °^rd

Z L N N WN

J n0 N ^... N N

W

= n Q

N

Z m

O y

W ¢

4

C a

Y

O' '_aJ W

S ^m n

N L 1

O 4N S Z y

N C

E 1 In

W 2 VY

W i?

^ fL-• N

1-. N

^ y

Z

O N

^ ^ 4

V N Y

W ^

^ r

C/1 r

•-I

W J 2 ^¢

Z LSO 

^ Q H N

I— T

SY

W C ¢

O

O F- M ^ U N

li Q ¢ 11 ^ W F--

•>i

v

N dY ^

O E ^m LL v

MY11 O Ndn9= '-•dl(IOmNq -WMMM=lc .-NOOmON dutb m g r b1 •

00 j C1 .+ OjO.r .y tnd OL;00.-^.y Nrl

M gg M1 q gmb.ynl00 .yghM1gM1mC m 41001 •+ n.•IN N.r .•.N ptOO gUfgbti

0000•+ O.r 'iN 1'r^N OO.+N O'n q^NI

mqm O MVb N Nb.rb mlllN MtOmMO gNbN.-1 .-.m bgm00

000 I r1 O'1 .-INMdYI 1 OONmm 1 1

q l(f0 I M m.-INhdMN Nggmmm nl0 n O N ti b O M O V n O IO O^ g m m h b N 1 .-I.-INNNm NNmV

NN 1 h^ 1 1 qIO •'I V •'. VgNgVmmN M m m N N b O d O^ m b b ti N M N M

10 d I b^ 'I I m M m mm g m g q V q q ^.••rN I o^..on 1 I N M .+ .+ ti .+

nN I I 1 WmW^N pp010101m^•Ymh tO O^ m^ d m b •"I .yNM NNM

0

m m

^O.•. Ob mbt01[IbNm bN^gVgmM1 40 n 1 rq•. II M ll) n^ f •'I b M N N M d 1 J n •w M

b

M^ In m In 1n

^

n d o ^ m M U'1 q ^ I 1 1 ^ N V n^ M d 10 ^ H ti . II N-^ .qa h l(1 N M

E o

E J

n N

q n 1 1 IH NbtiNO ^ .-.^M^^ I 1 VnNm E Ir+

~ ~ E

ra H N M

S m I I 1 OI N V n N m M b^^^ N N N M

O

0°000 c000°00 4 0 0 0 0 V V M c 0 0 0 bbmVV NOmMOq•+

I[I IfI N.^. 1C ^dNgbNd nO^m.+N

NmdbmO

n o Cn Lo no lno mn.Ndu1 M.wNYfmmV

dbmON Qlpm NtO r+lO ..'^ ."^ ••. r N N

1nb oln w vl oln Nm q.+r^M100 CgbdOd•^b

•-1 ti N (•1 f L. n m

n ouxmo m•+Ndbmmd

V lcmO N.-• •-. .-. N N FL .r O

N IOn N

Mdb 1 N

000 .+

•+mbNmmtO hOd..00V

Oti..NmV01

d'+IOdmNbM dbmMgNpb

OOOtiNbhq

m balm b aoln r.d g n Nrdi rdivugi o ln^

.+M Yb1mN •"I d M11wg0^ OOO C;

tO tO M.+h Nn.•.gOdm Nmbnn.-Inti

.•. 010 .•+r` ^lO b ri pl .-i Qbm^^ .M-••i OO O.^NpNn NM101Gq

mb0 M1bO M1N

1 q MOgM1r•MN MNngn

I 11 .+ O I(i Vbm ti01 ti .r b r• r•j O^ N O O .r N d NNm10bq

boM I o m.rdgd-.o IO IOOgmmom Nminnnodb

q r` M N . i 00 d 1(1 ra O) •+ O O O O .y to .ej 1[1 M M m ti ti N M N b q

65
0

C4

co

wx

fz

^o n

' w

H

a

z

z

a w • x

0z

a

N tY u

,,..^ W W

¢o

E o0

Q .. -'

^ oa

L) 11

w w

w w

H ^

CD

F 2

O

• U. w u x 2w ^-

wW

J in O

•O i- >

H

O w

O ?

F- N U ti

W !n

W wrr

• w W

O W N

O

N

N a

0

IO1

.-

w

,,KteiNAL PAGE 19

OF POOR QUALITY

s

0 OD __ O N O N v •O ao O° ^ O U O O O O O p ^

as/IW 4'll 1V IN 401) dP/dP] Bol ' '

66
ORIGINAL PAGE IS

OF POOR QUA LITY

A

67

§

^

$

$

8 k

f` & < _ ƒ¥ LU

\ ƒ^ <Mn ^

^ 

\' ƒ

^ /

§ R,

uj

k®\

QQ

*

» "o \^ \

.

. . £ §2

k k k = , ^e^u«

^

J:.

§ | | ƒ ^^

a 2 0 uj f.

®- C4 k § | |

| | k d

§ $ $ 2 A K A § 2

z

w© '2Anos @gWVIO- oHI

A <

\ \

n ^

'x \ui

3<

/\

f °& \ {/

Lu

2

o

LL. \\

LL 2

° \\

{

o°
simple fluid. The Jet A data particularly illustrate this point. At 6.1

ml/second, the product is 105, 101, and 109 in in-mm 2 for the three tubes.

There are two additional factors besides the viscoelastic die swell

which affect the throw as predicted by ballistics: aerodynamic drag and

stream breakup. Using our apparatus., Jet A breaks up after traveling about 40

inches, while AMK fuels stay together for about 120. If the stream breaks up,

the maximum density point of impact is reported. The 3.15 mm tube results are

slightly affected, and the .84 mm tube results ext: • emely influenced, by these

phenomena. Fortunately the effects cancel out for similar AMK fuels compared

with the same tube.

The differences between the three ICI AMK fuels are only seen, in the

throw-diameter squared data, for the largest tube. This is seen in Figure 21

by the extreme width of the shading of the 3.15 mm tube line. There are,

however, differences between the collective AMK behavior and Jet A. These are

best understood with reference to the shear rate. At a i of less than 2000

s- 1 , all AMK fuels and Jet A are identical. In the range 2000 to 9000 s-1,

the AMK are throw shortening. In the 1.37 mm tube data, there is a common

transition (which is not the critical shear rate) from throw shortening to

throw lengthening behavior at 32,000 s- 1 . In the 0.84 mm tube, the transition

to throw lengthening occurs at about 85,000 s- 1 , so this transition has a

diameter dependence. The smaller tubes will have to be operated at less than

9000 s- 1 to measure the more subtle effect of diameter on sensitivity. In the

throw lengthening regime, there are no distinctions between AMK trajectories.

The pressure drop phenomena are not biased by the drag and stream

breakup effects downstream of the nozzle. This allows comparisons between

results at different flow rates, with confidence and the dissection of some

diameter effects. There is a laminar to turbulent transition (Re = 2000) in

the available flow rate range with each tube, at 5930, 31,300 and 83,800 s-1,

but the laminar region is only significant for the largest tube. The pressure

increases linearly with flow rate in the laminar region, and with flow rate

squared in transitional flow. This enlarges the pressure measurement dynamic

range but does nothing to discriminate between AMK fuels. With the 3.15 mm

tube (L/D=48), the maximum AMK to Jet A pressure ratios are 3.1, 4.6, and 5.0

for AMK batches 232, 177, and 205, respectively. These ratios are seen as the

spacing between the Jet A and AMK curves in Figure 20, and occur at 4100 to

5500 inverse seconds. The ratios decrease at higher shear rate. The highest

pressure ratios in the 1.37 mm tube (L/D = 60) are 6.2, 6.9, and 8.1 respectively and occur at 17,000 s- 1 . The trend is that these pressure ratios would be

even higher when examined at lower flow rates. The smaller tube shows the

least difference between Jet A and AMK. It is unclear however, what the behavior would be much below 75,000 s- 1 . To summarize: the smaller diameter

tubes yield the best AMK-Jet A discrimination, and the 2000 to 9000 s' 1 region

where shear thickening sta, rts, yields the best discrimination between AMK

fuels.

The same three AMK fuels are compared through more detailed data and

with two additional AMK fuels in Table 23 and Figure 22. The most important

result is that all equilibrated AMK fuels are throw shortening: that is, they

travel less far than Newtonian fluids. The AMKs fal natura y into 2 groups.

AMK 160 and 232, old and new batches with FRs 25.2 and 30.5, show a plateau of

nonincreasing throw at 3700 to 4500 s- 1 . AMK fuels 177, 205, and 233, old,

58
I•

`IYK

YK` __r 1 ^S r

R

N

nm Ir)

m

m

sifiF2rL

pp ^^

•.

•O^ MNNw

O

N

t

!c

0

Y

YY

¢N

!Y, Q

cSY

Q

Q i;

G

qX

O

+

Q0 00

._n

a

R 'O

10

HOS

NR

fii yoN

m

g

N

O0

I

p

ORIGINAL 

PAGE 19

OF POOR QUALITY

NJW

LLYS¢OWcmY

J J

Crz w

i^ y

W 5

m^ O^

O Z U

O W

Qw Z

W Hf W

2 m vi U I-- N

omNN

OJL7

Q1 W 

(NI) MOVI

69
and new batches with filter ratios 49.7, 33.3, and 27.8 are actually throw

decreasing with flow rate in the range 2800 to 4000 s- 1 . The five AMK batches

are best separated at 3000 s- 1 and 4700 s- 1 . The maximum deviation of any AMK

from Jet A is about 14 inches out of 25 1/2 inches, by AMK batches 205 and 233

jointly at 4400 s- 1 . However, two other AMK batches differ from Jet A by only

5 inches at this y. All the AMK curves coalesce at higher shear rates. An

AMK-Jet A separation in every case of at least 8.5 inches is reached at 7500

s- 1 . Note that age and filter ratio do not correlate with the details of AMK

behavior in the throw test.

It is significant that the onset of high pressure drop correlates sample

by sample with the onset of throw shortening behavior for each of the 5 AMKs.

For example, for AMK 233, AP j umps at speed 250 where the first significant

(greater than three-quarter inch) trajectory deviation also occurs. The two

phenomena are linked.

The largest AMK pressure drop to Jet A pressure drop ratio appears with

;. every AMK to be bimodal. This is an artifact rather than actual behavior.

The dip between the maxima is due to the fact that the 450 and 500 speed Jet A

pressures (also 250 and 850) were measur ed in a different experiments, and are

slightly higher than the surrounding Jet A data. This lowers the AP ratios

slightly. The maximum discrimination of AMK and Jet A occurs at speed 450, rlf

4400 s-1 with AP ratios of from 3 to 5.2. The absolute magnitude of the pressure drop difference between AMK and Jet A continues to rise with flow rate,

(

w

("' but the ratios drop. Since the onset of pressure rise varies from batch to

ft° batch, the maximum discrimination between AMK fuels is obtained by measuring

APs at least 2 different flow rates, the first at 3000 s- 1 , the next one at

3500 s- 1 or 4500 s-1.

Table 21 and Figure 23 present flow rate scans with progressively more

degraded AMK fuels using the pressure drop technique with an orifice as an

exit section. Constant shearing rate is maintained by a constant speed drive

and orifice pressure drop is the dependent variable. The results are expressed as the ratio of pressure drop to shearing rate, AP /y, which is a measure of resistance to flow in viscosity units, or 'apparent viscosity'. Note

that the apparent viscosity, with values of some poise, is more an index of

E.^ entrance effects and shear thickening than of true viscosity, which is about

0.03 poise for undegraded AMK and 0.02 poise for Jet A. Above some critical

i value of f the apparent viscosity increases rapidly with y and nonsteady gel-

((( lation (due to backpressure partly stalling the pump) produces large amplitude

pressure fluctuations. The fluctuation envelope is indicated by the crosshatched regions of Figure 23. The critical shear rate of 2400 s- 1 for undegraded AMK measured with the orifice test is reasonably similar to the critical value of 3000 s- 1 mee;ured by Peng and Landel. As the polymer is degraded

(characterized by Filter Ratio) the critical shearing rate increases and the

apparent viscosity vrsF -is smaller. For undegraded AMK, the apparent viscosity jumps from 12 to 50 poise at 2400 s- 1 . At filter ratio 17, the rise is

from 13 to 22 poise at 430U s- 1 . At filter ratio 11, it is unclear whether

the gradual rise to 8 poise at 10,000 s-1 is shear thickening or just a Newtonian entrance effect. The above work utilized a 0.54 mm and a 0.71 mm ori-

°^ fice. The flew regime is definately laminar, with Reynolds numbers of 200 or

( less.

70
ORIGINAL PAGE 13

OF POOR QUALITY

N

C7

2

r

uj

W

r

o a0zin

Ln

w

K

Nw

w

co

W

H

WH

L1

r

m

z

C ' a

0 r G

w

z

co

w

^ ^ w0

H ^ = r

W

rX

W

N

MN

a

m

w

J ^J p 0 0

F

uj E ce

din W O. O

W V II I=Ip V aL^ V m

a u U^^ oe ,?-

0

n

II

nc

(13ONM1 'Ir JN3d) JoYI @ IN

h

Ce 0 0

$ g ^ o

oas• un/w6 ^ ^,/dv

71
Experiments with 0.54 mm orifice were also conducted using degraded fuel

ith filter ratio 1.5 to 3. In the y range available with the syringe oump,

bout 10,000 s- 1 , there were no critical transitions and even the apparent

iscosities were barely distinguishable from Jet A.

The final page of Table 21 presents laver data which is not graphed. In

ve 20,000 to 77,000 s" 1 range with a 1.31 mm orifice, there is an apparent

iscosity separation of undegraded AMK, filter ratio 6 AMK, and Jet A. There

are no critical transitions seen: undegraded AMK is past its transition and

we have never found one at filter ratio 6.

The largest sample-to-Jet A apparent viscosity ratios, e p uivalent to

pressure drop ratios, are found at the lower shear rates. At jigher flows,

the fluids are experiencing such strong forces that differences are masked.

Table 25 presents a similar stud y of the differences between degraded

samples and parent AMK or Jet A using a tube (rather than an orifice) as the

exit, section. There is some disagreement on the Jet A throw data, but this

does not affect overall conclusions. Undegraded AMK becomes throw shortening

somewhere between 3300 and 6000 s- 1 and maintains this behavior well past

19,800 s-1. The degraded (FR=6) sample has the best possible behavior, being

different from Jet A and even more different from its undegraded parent. It

becomes throw lengthening somewhere between 6200 and 9000 s- 1 and maintains

this well past 19,800 s-. Note that at low shear rates, before lengthening

or shortening behavior is observed, all samples behave as if they were Jet A.

Table 26 extends the throw and pressure drop data of the degraded sample of

Table 25 to orifice behavior. With a 2.53 min orifice, the degraded AMK shows

the same throw lengthening as with the 2.39 x 165 mm tube.

Consistent with Table 21, the degraded (FR=6) sample shows no critical

transition, and slightly greater than one pressure ratio (extending to

slightly less t"an one with the orifice) over the entire 3270 to 19,760 s-1

range.

Tables 27 and 28 demonstrate the ability of the pressure drop and trajectory tests to distinguish substandard developing batches from good AMK.

Batch 1 has the lowest quality of the two. Both experiments used the JPL inline blender. The first batch had an excessive deviation from plug flow, with

mixing of fluids as much as three minutes different in development time due to

the triple batch size. The second batch had excessive time between passes

leading to unintentional degradation. Both experiments show moderate throw

lengthening at 4000 s- 1 to well over 8600 s- 1 , This would categorize defective batches with degraded AMK fuels and successfully distinguishes them from

properly blended AMK. The throw lengthening increases somewhat with batch age.

The pressure behavior is more ambivalent. The better batch, number 2,

shows a sample to Jet A pressure drop ratio which increases with age: at

speed 800 the pressures are 1.74, 2.21, and 2.52 psi for ratios of 1.15, 1.46,

and 1.68, at 1 hour, 3 hours, and 1 day, respectively. The poorer lot shows

the opposite behavior with time. A critical transition is weak and around

y = 8600 S-1.

72
iaDle 25. EXTENT OF DEGRADATION BY TUBE PRESSURE DROP TESTING AND TRAJECTORY

ANALYSIS

Flowrate Pump y AMK Jet A FR 6.4

(Ti /s) Speed (s'1) 160* (Ref) DC-10 Sample

Jet A

(Ref)

Throw (in)

4.37 000 3,270 13 13 18 18

6.10 100 4,560 --- --- 29 28

8.Z5 200 6,115 14.5 30 38

12.5 400 9,355 27.8 38 51

16.8 600 12,530 44.5 52 67

21.8 800 16,300 60 67 85

26.4 1000 19,760 76.5 82.5 102

Pressure Drop (psi)

4.37 000 3,270 0.53 0.49 0.45 0.41

6.10 100 4,560 --- --- 0.83 0.67

8.25 200 6,175 5.24 1.17 1.23 1.15

12.5 400 9,355 9.42 2.47 2.40 2.45

16.8 600 12,530 12.86 4.22 --- 4.16

21.8 800 16,300 16.6" 7.41 7.03 6.35

26.4 1000 10,760 18.82 8.77 9.89 8.75

*AMK RMH 1-160 slightly degraded by inverting the supply bottle 29 times.

The AMK and associated Jet A reference data are excerpted from Table 29.

k

*Center position of a spray.

Exit Section: 2.39 mm ID x 165 mm Tube

73

Al
Table 26. COMPARISON OF TUBE AND ORIFICE EXIT SECTIONS FOR

TRAJECTORY ANALYSIS AND PRESSURE DROP TESTING USING

DEGRADED AMK AND JET A

Pump y Throw (in) Pressure Drop (psi)

I., Speed (s' 1 ) FR 6.3 FR 6.4 Jet A FR 6.3 FR 6.4 Jet A

,i 2.53 mm ID Orifice

I; 000 2755 18 18 18 0.09 0.09 0.11; 0.10

'I 050 3385 22 21 0.12 0.135

100 3845 25 0.14 0.16 0.18; 0.16

200 b205 34 34 35 0,28 0.28 0.29

C.

300 6615 43 0.41

i 400 7890 50 51 50 0.55 0.59 0.59; 0.59

500 9280 59 0.78

g 600 10570 69 67 1.11 1,02

800 13750 86 82 1.73 1.62

{ 1000 16660 102 104 100 1.99 2.51 2.20; 2.16

2.39 mm ID x 165 mm Tube*

000 3270 18 18 0.45 0.41

100 4560 29 28 0.83 0.67

200 6175 37 38 1.23 1.15

r 400 9355 58 51 2.40 2.45

800 16300 102 85 7.03 6.35

y 1000 19760 124 102 9.89 8.75

*These data are excerpted from Table 25.

r

^s

,' 74
MNm

L L D

ro ro ro

m m 

H ro ro

C- O

C C L

E ENn^

O 41

X +1d

N N O L

v 0 . u

00 U

N N X

ro ro

a

CL 0.

n a

N N N L

ro I 1 m

ro O) 0) Y Y y .. ro C O m OUU Y N a) a

V)

U 

t

uu++al

+) + • X

L

roro x, mmw^

il

Y mW LnnM Oto m a

0 0 0 Cl 0 N .-I .-1

N

aro

ON

V

I

I

rl 1 I lA 1 rU

O r/ 1 1 0 1 1 I N I co

00

L

N LnO

0

O

a) ! LN 2_ Ln m lfl (7) 01 N.L er 1p r 1 09 m N r+ r N 1 L m C; 0 C 1 O.--tNM V d N I NL L Ol O i n lA a' U L M ID tit I I r 0 4 1 1 M '-I O O O I O I .-i m a m N r b .-1 x114 m Om A u U N V cr In ID 1 rOtom ro ION uLC) 1 -0000 0 0 0 1 0 .-1 .ti N N Lr) O O

N N O V Ln

N er ct

O

t

LL

DL In r v Ol f-I l{)

a' l0 lO

L 0 Cl 0 1 0 1 r I N O) NNa L L L to N O) ITm 41 t

^Ln LDo IO m Q\ I,nM rLO

W

NI O O O O O O N Ol t L

UZ raN 00 to

ro 'i

1

m

I O O O 1 0 .-1 .-( Nr

N CD L Ln In Ln to Cl Ln

O)

y

rNrr 00

.N.. lO :t zk x-110 NMcrZr ch fo r m

+

o

N

O

r0 1-v

D }^

E a) 0 C) C) ro a)00 4- E N CD tn OLn 0000 L 00 a) O C1 NM-^tcr tl7 In W O ..-N TIY CL ti) '-I L Wv o ¢

+ 4 al Q r H a a) i= ! U 22 LL ( ) W n N"7

a)

4J

ro N m Ot t) Ner In lO lO a(J mom' 3^\ O E m .-•! N m er t0 .--t to r- ^ ti .-1 N N '-I N N W

YfQWG

IJJmYJNWWWa

r-I UWWWOWO

C7Z

f-NWdO

tYOWs

V)NNWdWm7

r_rN

a1

ro

F75
1

JWC

lLWHUWWWp

CL,

WO

V)NJZ

CD

tiU Y W F ^0 G

K p

F- Wp

W Z

co W

F- J

F- co WNaa

ro i-

¢

* 00

M

4

J b N d• LD t^ Oi N n a 'rN NNNN McP 7

U

U >1 o n

ro

0

'O 1 I L[ 1 1 1 N 1 00

O

NaN Zt

O

-e

t

3

cr

L In co to to 1^ L ^t 1

F- bMto

O

M V'.

a

m .r NN C1M eYNN

tt

L to to L

b N q• I O1 1 0m q• N N N V to N

b

U U U

00 to to to

^

1a 0 0 i c,

Lom m u;c4 NM toOO LOo . r N N t V M cf L o N N O a' LO

L.. 00 Cl) to L17 LO L 1

3

c 01

O C

a

LO M

m

tT I my

.-+ N N

N a to .-t L •^

HV

L 00 LO lf7 to Ln

W

t

nMtoCnjC

m

a rn

N tiNNNNMCf to r•s ! e L co Cl) to co M .-t

LD M Lo1 0l to d'M 1:

N .-1 N N N m d' LO ^•-t I t . 1

VON O •rl CD to Lo to Lo O C)

rner1DN ^oo^ n aN

N 'J7

m O a' n LO . 00 .- I--

•^-

N m a c q• Lnm .J

roaoow

Y L 0 0 

a

O N T CX Q. a L L

E a 0 0 0 0 0 0 0

a 'u-0 ¢ II 0

otno n0000 + ¢ a a t1N NMChaLOt000O a a++

^-+

-,U. U C

L CL QJ

a

6 <L I) t NN7

m

ro n L \ to C^ to

OE Wv^ LO tD t0 06 00 V' .

IX. r1NM 

q' 1p.-^l0 LL.^ .-t .-t N .-. '-1 N N

MNa

L L f]

ro o ro

CL 1

H

ro ro

o

C C

L

N W

E E Lnr

oW

a

X iJCL 00 p L as •^.a

N NU

HN

X

M, ro

a

a CL

LO a N N ti L

ro

I I

m

ro

m m DY Y 0 -0 M O ¢ .

U•.

U N N N a a t/) 7 L C

u u 1J v

ro m X Fm m Wit

7G
The anomalous behavior of AMK as judged by the filter ratio test when

diluted with Jet A or low temperature degraded has been discussed earlier.

Tables 29 and 30 demonstrate the extent to which the pressure drop and trajectory analysis identify or ignore these effects.

Jet A dilution converts throw shortening shaken AMK (20 bottle inversions

and some swirling) into throw lengthening diluted AMK. The 0.2% polymer

diluted fuel fails the FCTA with a flame temperature half that of Jet A (see

Table 19). Therefore the trajectory test is successful when it lumps diluted

and degraded AMK fuels together, since both fail the fire test. With the 3.15

mm tube, the diluted samples track Jet A to shear rates of 4425 s- 1 , for 0.2%,

and to 4775 s- 1 , for 0.1%. With the 2.39 mm tube, the diluted AMK fuels do not

throw lengthen until 9355 s- 1 . With either tube, the greater the dilution, the

greater the throw lengthening.

The pressure drop ratios do not separate 0.2% diluted AMK from shaken

AMK as well as the throw test. At 5475 s- 1 with the 3.15 mm tube, shaker. AMK

has a 3.24 pressure ratio, while 0 . 2% diluted A.MK is at 1 . 40, and 0 . 1% diluted

AMK is demonstrating polymer drag reduction effects with a pressure ratio of

0.92. The 2.39 mm tube is superior for distinguishing these samples, with

pressure ratios at 9355 s- 1 of 3.81, 1.69, and 0.94, respectively. The diluted samples are also different from virgin AMK in tracking the Jet A pressures until higher shear rates are reached.

The difference between AMK and shaken AMK (20 bottle inversions and some

swirling) shows that both quality control tests are quite sensitive to the

initial degradation. AMK was shaken as a control for the degradation due to

the mixing itself when the AMK was diluted. The maximum sample to Jet A pres-

^.ure drop ratios occurred at speeds 450 and 600, or 4425 and 4575 s- 1 with the

3.15 mm tube for the ICI AMK fuels discussed in Table 23. The same location,

speed 600, is seen in this data. Shaking reduces the maximum pressure ratio

from 3.39 to 3.24. The throw length is even strongly affected, the throw

shortening being reduced by 1.5 inches out of a sample to Jet A shortening of 2

to 9 inches.

Table 30 presents the data for an analysis of low temperature degraded

AMK. With the 152 mm tube, throws are virtually identical before and after

the test, despite a doubling of the filter ratio by pumping. Both show a behavior not seen before, of being slightly throw lengthening from 3400 to 7100

S-1, and throw shortening, like an undegraded AMK above that. With the longer

370 mm tube, again the throws before and after pumping are identical, but the

behavior changes to progressively throw lengthening. This might be explained

by excessive sample degradation in the longer tube itself. This would be consistent with the conclusions from Table 22.

The pressure drops before and after the pump samples are about the same

for either tube length, as desired. The shorter 3.15 mm tube produced only a

gradual increase of AMK-to-Jet A pressure dro,; ratio from 1.34 to 2.21 over

the 2690 to 8605 s-1 measurement range, while the longer tube did have a

slight critical transition • at about 5500 s- 1 . Its pressure ratios were 0.96,

1.23, and 1.74 at 2690, 5500, and 8600 s- 1 , respectively.

77
Table 29. TUBE PRESSURE DROP AND TRAJECTORY ANALYSIS OF AMK DILUTED WITH JET A

AMK Shaken Diluted Diluted

Flowrate Pump Y 160 AMK` to to Jet A

(ml/s) Speed (s-1) 0.3%) (0.3%) 0.2% 0.1%

3.15 mm D x 152 mm length - row to

4.37 000 1425 6.5 6.5 6.8 6.3**

6.10 100 1990 11.3 - 11.5 10.8 11

8.25 200 2690 16 16 15.5 - 16

9.37 250 3055 - - 18 - 18

10.48 300 3415 19.5 19.8 20 19.5 19.5

11.49 350 3745 20.8 21.5 - - 22.8

12.5 400 4075 20.5 22 24.5 24.5 24

13.6 450 4425 20.3 - 27.5 25.5 26.3

14.65 500 4775 21 22.8 29.3 29 27

16.8 600 5475 23 24.5 33.5 -34 29

21.8 800 7100 29.5 - - -43 38

26. 4 1000 8605 38 39 49 52.5 47

Gauge 11 - 2.39 mm ID x 6.5 mm enyt - Throw (in)

4.37 000 3270 - 13 13 12.8 13***

8.25 200 6175 - 14.5 29.5 28.5 30***

12.5 400 9355 - 27.8 Q3 46 38***

16.8 600 12530 - 44.5 55 62 52***

21.8 800 16300 - 60 70 69 67***

26 4 1000 19760 - 76.5 - - 82.5**

3.15 mm ID x 152 mm length - Pressure Drop psi

4.37 000 1425 0.22 0.25 0.21 - 0.24**

6.10 100 1990 0.32 - 0.29 0.24 0.34

8.25 200 2690 0.40 0.43 0.39 - 0.34

9.37 250 3055 - - 0.51 - 0.49

10.48 300 3415 0.68 0.64 0.48 0.43 0.49

11.49 350 3745 1.21 0.96 - - 0.62

12.5 400 4075 1.64 1.50 0.57 0.59 0.59

13.6 450 4425 2.14 - C.80 0.73 0.74

14.65 500 4775 2.31 1.08 0.77 0.89

16.8 600 5475 3.39 3.24 1.40 0.92 1.00

21.9 800 7100 5.01 - - 1.48 1.51

26.4 1000 8605 6.25 6.03 3,03 1.8 6 1.98

Gauge 11 - 2.39 mm ID :< 165 mm engt - Pressure Drop psi;

4.37 000 3270 - 0.53 0.52, 0.58 0.49

8.25 200 6175 - 5.24 1.74 1.11 1.17

12.5 400 9355 - 9.42 4.18 2.31 2.47

16.8 600 12530 - 12.86 6.67 4.19 4.22

21.8 800 16300 - 16.67 9.25 5.74 7.41

26.4 1000 19760 - 18.82 - - 5.77

"A control batch of AMK which had experienced the same mixing forces and

shear as invlved in the dilution process.

**The 3.15 mm Jet A data are excerpted from Table 23.

***Center point of a spray, ratifier than a single stream..

78
;I

Table 30. TUBE PRESSURE DROP AND TRAJECTORY ANALYSIS OF AMK DEGRADED AT LOW

TEMPERATURE

Flowrate

(ml/s)

Pump

Speed

y

(s- 1 )

^hrow (in)

Before After

Pump Pump

**

Jet A

Pressure Drop

Before After

Pump Pump

(psi)**

Jet A

3.1 mm ID x 152 mm Tube L D = 48

8.25 200 2690 16.5 16.8 15.8 0.45 0.41 0.32

10.48 300 3415 20.8 21 20. 0.57 0.52 0.47

11.49 350 3745 23 22.8 22. 0.71 0.64 0.53

12.5 400 4075 - 25.3 24.5 - 0.74 0.62

13.6 450 4425 27.8 27.5 26.3 0.90 0.91 0.69

14.65 500 4775 30 30.3 27.3 1.10 1.09 0.72

16.8 600 5475 33.5 33.5 30.3 1.70 1.88 0.98

21.8 800 7100 38 "39 -39 3.44 3.49 1.59

26.4 1000 8605 -43 "44 -47 5.12 5.28 2.35

3.15 mm ID x 370 mm L D = 118

8.25 200 2690 16.5 16.3 16 0.57 0.57 0.59

10.48 300 3415 21 21 20 0.75 0.76 0.81

11.49 350 3745 23.3 23 22.5 0.85 0.94 0.88

12.5 400 4075 25.5 25.3 25.3 1.01 1.21 1.05

13.6 450 4425 28 27.8 27.5 1.32 1.32 1.11

14.65 500 4775 30 30 -29.5 1.21 1.52 1.20

16.8 600 5475 "35 "36.5 -29.5 2.19 2.18 1.77

21.8 800 710E "44 -44 -38.5 4.39 4.37 2.77

26.4 1000 8605 49.3 49.3 -46 6.33 6.80 3.78

Sample Tested 27° C 27° C

Temp.

Filter Ratio 34.4 56.8

Cup Test 3.2 3.3

FCTA Fire Test 25° C 50° C

Speed 200

Speed 900 150° C 200° C

Jet A Ref. " 450° C

*JPL Wing tank Simulator sample; using AMK RMH 1-205; final -44° C.

**These data are excerpted from Table 22.

79
3.4 Discussion and Summary

By using a rapid dispersion technique (static mixer) at relatively

moderate shear conditions, FM-9 slurry was blended in Jet A to produce AMK.

The parameters which influence the polymer dissolution rate, were identified

and attempts were made to optimize some of them. The main efforts were in the

area of mixing and the area of polymer particle size. Work concentrated exclusively on metering the additive in the slurry form as received from ICI.

To avoid batch to batch variation, only one slurry lot was used in the entire

program and no attempts were made to modify the chemistry of the slurry.

The AMK was prepared in an in-line blending apparatus, which has a

static mixer as the main component of the unit. The in-line blender was a

bench top unit and produced AMK at a maximum flow rate of one liter per

minute. The unit produced AMK in a 1-pass or 2-pass mode and the only significant difference between the two is the degradability of the AMK. With

both methods, stable homogeneous despersions of the polymer in the fuel were

obtained, which with time, produced fully equilibrated AMK.

Fire test (FCTA) studies on in-line blended AMK indicated that the fuel

developed adequate fire-suppressing properties within a short time. The 2-

pass method produced AMK which has adequate fire-protection properties in 10-

lb minutes after blending and the 1-pass method within 20-30 minutes.

The degradability of AMK was assessed by comparing the degradability of

freshly blended and equilibrated sample. This was done by establishing the

time after blending at which a developing sample, if degraded, will show the

same degree of degradation (by filter ratio) as equilibrated AMK. After that

period, the sample was considered to be fully equilibrated. By using this

method, it was found that maximum degradability is reached much after adequate

fire protection is obtained. The results confirmed the concept that maximum

degradability should be reached when the polymer has reached its dissolution

equilibrium in the fuel. The data also confirmed results by RAE (Reference

15) that freshly blended AMK resists mechanical degradation and will require

significantly more energy than equilibrated AMK to degrade to the same level

of degradation as measured by filter ratio.

When analyzed for degradability, the difference between 1-pass and 2-

pass freshly blended AMK becomes significant. Again, 2-pass material developed maximum degradability in 4 to 6 hours, while for the 1-pass AMK takes ten

hours longer. The improvement in the degradability of the 2-pass material was

obtained by breakup of the partially swollen polymer particles formed during

the wait period (5 minutes) between passes which "n turn, facilitates the mass

transport from the particle to the fuel. It is clear that homogeneous dispersion of the polymer (in a slurry form as currently constituted) in jet fuel

via single-stage in-line blending is feasible. There is a strong indication

that the problem with the degradability of the freshly blended .AMK is not as

such an additive dispersion problem, but depends more on the rate of polymer

dissolution. If polymer chemistry must remain the same, then additional work,

is needed in other areas such as particle porosity, polymer surface.properties, etc, which may improve the rate of dissolution. It should be noted that

these results are based on experiments with one batch of slurry as supplied by

ICI.

80
In summary, the data indicates that FM-9 can be in-'Me blended and that

static mixer technology can be used for obtaining satisfactory polymer/fuel

dispersions. The unit repeatedly produced high quality AMK with very little

variation in it's properties as characterized ,.,/ the standard AMK Quality

Control methods. The fuel quality and the reproducibility enable us to

support other on-going programs such as base fuel affects on A11K (Section

2.0), and development of Quality Control methods for AMK.

In the area of Quality Control method the Filter Ratio test has evolved

to be the workhorse of present quality control methods. However, there are at

least four cases where its reliability is questionable: (1) If an AMK has a

low temperature history, it can have a higher Filter Ratio than the starting

material, even though it has been partially degraded. (2) When AMK is diluted

with jet fuel, the fire protection is quickly lost (with less than one-half

part Jet A per part AMK, 0.3% polymer) but the filter ratio actually increases. The cup test is also misleading. Though the volume passed increases

with dilution as expected, the fire protection of diluted AMK at a given cup

test value is much less than that of a degraded AMK with the same cup test

result. (3) When the polymer slurry is improperly blended, particles remain

so that the fuel has poor fire protection, despite filter ratio values which

range from apparently good to extremely high. (4) Quantification of degraded

samp les with filter ratios as low as 1.1 is desired. In this case, the filter

ratio test is not misleading, but is insensitive. Improved tests are thus

required.

Six of the quality control tests, i.e., cup, filter ratio, orifice pressure drop, tube pressure drop, orifice trajectory, and tube trajectory analysis, operate by some combination of Newtonian entrance effects, Newtonian

bulk viscosity resistance to flow, and rheopectic shear induced stiffness in

passages where the shear rate must be large. The pressure drop tests measure

the same behavior as the filter ratio test in a single, larger passage. Trajectory analysis is based on the fact that recovery from viscoelastic effects

are time dependent so that there may be a relaxation of the exiting fuel.

Note that each flow test could be implemented in two ways, with constant pressure measuring flow, or constant flow with pressure drop measurement. Much of

this development work involved testing at a range of flow rates, shear rates,

and geometric dimensions to obtain extensive data. Application in the field

should probebly involve scanning the blended AMK at one or a rew fixed conditions which are chosen to give maximum descrimination. The extensive data

tables are presented in part to allow these conditions to be identified at

some future time.

Nephelometry is not related to these six in any direct way. Its principle of operation is different. In the developing AMK, secondary particlejet fuel mixture, or polymer powder-jet fuel mixture, there are inhonogeneities which can be at various times dry particles, wet particles, gels, solvent swollen polymer, and polymer solution concentrates. To the extent that

these different components have differing refractive indices, there will be

enhanced light scattering, a more turbid fluid. Thus nephelometry is a useful

and particularly easy non-destructive test for the purpose of following developing batches of AMK. It has some limitations which should be appreciated before it is used, however. Foremost is the fact that turbidity reaches its

equilibrium value after 6 hours, whereas batches require 10 hours at a minimum

and up to 5 days to reach full degradability equilibrium.

01
1

The filter ratio test, by contrast, is useful for almost all of the development. With this nephelometer, there is about a 15° C rise in sample temperature when the sample remains in the light beam. With most developing and

equilibrated AMK this only causes an 0.2 FTU change in a 5-15 FTU value, but

one AMK experienced a 6 FTU change. The turbidity of developing AMY, always

exhibits a steady decreasing behavior, regardless of the filter ratio. Some

slightly off-blended batches will have a filter ratio over 50 for the first

half hour, and nephelometry does well to ignore this artifact. However, defective AMK which plugs filter screens does not show significantly different

turbidity behavior. Water is also a factor. Fresh AMK has a turbidity of

4.2-5 FTU, while year old AMK is at about 7 FTU. Keeping the above problems

in mind, a nephelometer with a flow through cell attachment offers very simple

continuous monitoring capability and can be used as a real time in-line quality control device.

The FCTA fire test data from DC-10 simulator samples correlate with filter ratio only slightly better when collected with a calorimeter than a fast

thermocouple. If FR > 17, a sample will most likely pass the fire test; if

filter ratio < 7, it will fail. A pass is defined for this usage as a temperature rise of less than 17% of that for Jet A, or about 75°C at a fuel speed

setting of 200.

AMK filter ratio is increased by the addition of Jet A diluent and may

exceed 100 while there is absolutely no fire protection. Also, a diluted AMK

has much less fire protection than a degraded AMK at the same cup test value.

This behavior does not occur when the diluent is degraded (filter ratio less

than 2) AMK. Similar results on dilution of AMK with Jet A and glycol containing Jet A have been reported by RAE (Reference 16). The pressure drop and

trajectory analysis tests are consistent with the fire protection results.

The tube exit section trajectory analysis, or throw test, can be used to

follow the development (dissolution) of freshly blended AMK. The throw test

does not give misleading results for fuel with low temperature degradation

history except that a low temperature history may distort the trajectory shear

rate curve into a unique shape regardless of degradation.

ine trajectory analysis depends on the plastic phenomenon of die swell.

Since horizontal distance traveled by a fluid across a constant vertical drop

from a horizontal nozzle is linearly related to the fluid exit velocity, throw

varies with volumetric flow rate divided by the fluid cross-sectional area.

This means that the product of the throw and the exit cross-section, is the

appropriate parameter for analysis, as it varies only with flow rate and die

swell. Die swell is the quotient of the exit section and the average fluid

cross-sections. Undegraded AMK swells at certain shear rates, so its travel

is actually shortened. Degraded and defective AMK, on the other hand, necks

down. Its throw is extended relative to Jet A. This opposition of effects

gives the trajectory analysis its sensitivity and discrimination.

Tube length is important. A tube of L/D (length to diameter, ratio) 48

was found to have twice the sensitivity of a tube with L/D 118. We were not

able to isolate the effect of diameter on sensitivity. Diameter changes with

our apparatus resulted in large changes in shear rate. At y less than 2000

s- 1 all AMK fuels behave as if they were Jet A. From 2,000 to at least 20,0;

s ••1 , AMKs are throw shortening. At higher shear rates there is a transition

82
to throwlengthening behavior. This is diameter dependent, occurring at

32,000 s- I with a 1.37mm tube and rising to 85,000 s with a 0.84 min

The change in the behavior of AMK to that typical of degraded AMK is probably

due to degradation during the test at high shear rates.

The maximum practical throw without stream breakup is about 40 inches for

Jet A and 120 inches for degraded AMK (filter ratio > 2) An inclined ramp

for fluid impact could limit the maximum throw to 40 inches with only a slight

increase in complexity. Absolute distances of course depend on the apparatus

geometry. In this work,the exit section was horizontal and connected directly

to the FCTA Fuel pump.

The choice of shear rates for optimu m sample discrimination depends on

the application, and also on tube diameter. Furthermore, with a 315 mm tube,

the maximum deviation from Jet A by any AMK was achieved jointly by AMK 205

and AMK 233 at 4400 s- 1 , a deviation of 14 inches out of 25 inches. 'There is

a large envelope to A14K behavior at this point so to guarantee a more

significant reading, all virgin AMK trajectories coalesce at 7500 s- 1 to give

about an 8 inch deviation out of 40 inches. Substandard developing AMK is

throw lengthening starting about 4000 s- I . Jet A diluted AMK fuels initiate

lengthening at 4500 to 5000 s-1.

The pressure drop tests are also reliable in every circumstance tested,

but lack sensitivity. Altering tube length from L/D = 48 to 118 and reducing

the exit section to an orifice do little to affect the sensitivity. Smaller

tube sizes do improve the test. AMK to Jet A pressure drop ratios peak at

about 3 to 5 for undegraded AMK at about 4400 s- 1 with a 3.15 min tube, and at

6 to 8 for a 1.37 min tube (L/D = 60) at 17000 s- 1 (and may i ncrease at lower y

with the 1.37 

min The maximum discrimination of undegraded AMK fuels

from Jet A occurs at 4400 s- 1 (3.15 

min but the maximum discrimination

between AMK fuels is available by observing the range of onset of thickening.

For this purpose, testing at 3000 s- 1 and 3500 and/or 4500 s- 1 is best.

Substandard developing AMK fuels have peak pressure ratios on the order of 2,

rather than 3-5, for good quality AMK.

Critical shear transitions have only been observed with samples of filter

ratio > 17 or possibly FR 11. Only the apparent viscosity difference from

Jet A characterizes more degraded samples down to about filter ratio of 5.

Shear rates in the 20,000 to 100,000 s- I range are more conducive to this.

Highly degraded samples have not been successfully characterized. Tube results have been at least as good as, orifice results.

In summary, the data siggests that with some refinement and automation

both trajectory and pressure dro p measurements can be modified and employed as

real time in-line quality control field instruments.

3.5 Conclusions

Conclusions for Section 2. Effect of Base Fuel Composition on AMK

Performance:

1. Significant compositional differences for base fuel (Jet A) within

the ASTM specification D1655 that were expected to be relevant to AMK

83
2rties were found, but with the exception of aromatic content, these

ations did not significantly alter the AMK characteristics.

2. The increase of the aromatic content of the base fuel was found to

be beneficial for the polymer dissolution at ambient (20°C) temperature.

3. It was demonstrated that by using static mixer technology the

antimisting additive (FM-9) can be in-line blended with Jet A, producing AMK

which has adequate fire-protection properties.

Conclusions for Section 3. AMK Blending and Quality Control Techniques:

1. Comparing the degradability of freshly blended and equilibrated AMK

indicated that maximum degradability is reached much after adequate fire

protection is obtained. At the dissolution equilibrium the degradability (as

measured by FR) is highest.

2. The results of AMK degradability as measured by filter ratio confirmed previous RAE data that power reauiren^pnts to degrade freshly blended

AMK are significantly higher than equilibrated AMK.

3. Nephelometry offers simple continuous monitoring capability A nd can

he used as a real time quality control device for AMK. The data indica;.es

that it should not be used as the sole quality control device, but in parallel

with another instrument.

t thrust) and pressure drop tests

ating AMK quality and their field

Id be further evaluated.

84

are useful laboraapplications as
REFERENCES

1. E. Klueg, 6th US/UK Technical Committee Meeting on Antimisting Fuels,

1980.

2. Encyclopedia of Chem. Technology, Vol. 3.

3. "Evaluation of World's Important Crudes," Oil and Gas Journal, 1973.

4. "A Guide to World Export Crudes," Oil and Gas Journal, 1976.

5. R. Friedman, Aviation Turbine Fuel Properties and Their Trends, NASA

Technical Memorandum 82603.

6. E. M. Shelton, Aviation Turbine Fuels, 1980. DOE/BETC/PPS-el/2.

7. T. I. Eklund and W. E. Neese, Desi n of an k aratus for Testing the

Flammability of Fuel Sprays, FAA Report FAA-RD-785 (1978).

8. A. M. Ferrara, Laboratory Scale Testing_ of Modified Fuels, FAA report to

be published.

9. R. J. Mannheimer, IAA-RD-79-62, 1979.

10. A. H. Yavrouian, M. Sarboluki, V. Sarohia, Influence ^f Liquid Water and

Water Vapor on Antimisting Kerosene (AMK), DOT FAA CT-,-9.F'18.

11. S. T. J. Peng, R. F. Lan "el , "Rheological Behavior of Progressively Shear

Thickening Solutions," J. Appl. Phys., 52, 1981.

12. A. J. Fiorentino, J. R. Planeli, An Assessment of the Use of Antimisting

Kerosene in Turbofan Engines, NASA'CR-16f6 ,PW 5W-bb- NASA/FAA report, coer

13. F. Y. Ching, A. T. Pe.e,cock, Com 17i IF 

Stud bf Antimistin Kerosene

and the DC-10/KC-10 Fuel System, DOT FAA CT-82 116 1982

14. R. Fleeter, R. A. Petersen, R. D. Toaz, A. Jakub, V. Sarohia,

"Antimisting Kerosene Atomization and Flammability," JPL Publication

82-40, July 1982.

15. E. Timby, S. P. Wilford, J. Knight, 8th Technical Group Meeting, RAE

Report. --

16. E. Timby, S. P. Wilford, 10th Technical Group Meeting, RAE Report.
O

ti

17'1

0

tr10

N

m

Kr

O

4

vr

N

a

In

Q

Z

Q

Z

L.

A D

O a) Op

N U N

L- C, m a

v v a

N U N

O A O

L

m a) a

N U N

L

o m o

:o

N L1 N

L.

O Ia N

!^ al H

N U r

m

L

O RI M

10 al 1^

N U N

L

10 10 f

In a) t^

N U N

Cl) M N N 00 O

M dr N \ to tD N O

N N

M co N \ 1h 1 N O a

N rl m N

\ m Z In O

E

O_

r N m m N \ h

1 M O a

N m N \ m ^ M O

K

to

O .•r N co M 1 \ O O r n m M

\ co 2 N O

K

n

a W

OD

1 \ o

I m o a

N r-1 m N

m

2 •\-I O

K ~

t` 00

O

\ O O

1 CI' to N

'-I rl t0 m

= O O

E[Y

N

n

00

m

\ O I^

I '-1 a

N

m

a N

00 O

CC

O

ko

OD I \ O O

.+ m 00 m

\ 0) O

ORIGINAL 

PAOf Or POOR QUALII

L

r d cc Lo

r •

N U N 00

C"

^

O O

.r

L d 1]

a) a _^ >1 m

.1] •r VI Ll 4J CL'

E r v O n U

Z N C .r U N N LO 00 a)

Y 4-1 O N O\ m N N r

O cc E r r r

J O ¢ ae W E v ta_

n-1i

J

d.

7

Y O

m m

x o oI

W m O ? f C •-+ Ucu W 1 G U Y Cl. W f

Q 4

Y

Q
Appendix B

OPERATING PROCEDURE FOR FILTER RATIO TEST

Fuel temperatures for Jet A and AMK are 20 ±1° C.

Apparatus: Filtration ratio apparatus as shown in Appendix C.

Type of filter used: 16 -18P twilled Dutch weave stainless steel 155 X

1400 mesh cloth, warp diameter 0.07 mm and weft diameter 0.04 mm, pre-cut into

discs of 44.5 mm diameter. The material is obtained from Tetco, Inc., 525

Monterey Pass Road, Monterey Park., CA 91754.

1. Make sure filter apparatus has been rinsed clean with jet A and then

drained. Residual AMK can influence the filter, time of the next sample.

2. Place an unused filter on lower filter plate, positioning it in the

center so that it overlaps the edge of the orifice.

3. Both '0' rings should be properly seated. Align upper and lower filter

plates the same way each time; attach lower to upper and apply screws,

tightening them to the same tolerance each time.

4. Insert a rubber stopper in bottom orifice, choosing a size which does not

contact the filter. Hold stopper steady until removal. Excess motion

may induce gelation in the filter.

5,. Tilt apparatus to diagonal and pour the reference jet A slowly down

side of tube.

6. Once tube is about 3/4 filled, return it to vertical, add fuel till

it overflows into gallery.

7. Remove rubber stopper. Record time between timing reference points.

8. When apparatus has drained, replace stopper, tilt apparatus to diagonal

and pour sample AMK slowly (90 seconds) down side of tube, not letting it

hit bottom directly.

" 9. Repeat step 6.

10. Wait 60 seconds (fuel relaxation time) before removing stopper. Remove

_

it slowly and gently with a turning motion to avoid causing suction.

11. Record time between timing reference points.

12. Dismantle lower filter plate and discard used filter. Rinse and

drain apparatus.

l

S-1
31. aAM.

1416"

owl a 0490

ORIGINAL PAGE 19

OF POOR QUALITY

t Appendix C.

DESCRIPTION OF FILTER SCREEN DEVICE
Appendix D

OPERATING PROCEDURE FOR FCTA TEST

A special run procedure, described below, was devised for the FCTA to

enable rapid relative flammability measurement for quality control tests only.

This procedure yields a single-point flammability measurement and is not

intended to replace standard FCTA procedure. It was incorporated because of

the need to carry out testing on a routine basis.

1. The speed control dial which controls the fuel injection rate is set*

at 900 for undegraded fuel, 200 for degraded fuel and Jet A.

2. The air accumulator tank pressure which determines the air flow rate

is allowed to climb to 6.5 atm (95 lb in- 2 ), This reading is taken

at the highest pressure reached during the run and occurs just as the

air begins to flow through the nozzle.

3. Temperature measurements are made with a 0.76 mm diameter lead,

chromel-alumel thermocouple. The probe is placed level with and 25 cm

downstream of the exit flange tip. Thermocouple readings are made

with a strip chart recorder set so that a 1 mm deflection (the

minimum resolvable) corresponds to a 24 0 temperature change.

4. A series of runs is performed until these tests yield results consistent within the measuring precision of ±12° C.

* The flow rate for the various settings can be found on Table 22.

D-1
Appendix E

OPERATING PROCEDURE FOR ICI CUP TEST

CLEANING PROCEDURE:

1. Place cup in Jet-A. Fill cup about half way w/Jet-A.

2. Sonicate for 30 seconds in Jet-A fuel; power rating at 7.

3. Blow until dry with 25 psi nitrogen (1/4" hose). It is important that

the area around the hole both inside and out, is completely dry and

void of any particles.

OPERATING PROCEDURE:

1. Suspend cup inside ring on ring stand; allow enough room below cup to

permit introduction of graduated cylinder (preferably 10 cc).

2. Place finger over the hole, tilt cup slightly to one side. Pour in

fuel sample allowing fuel to run down the sides of the cup rather

than hitting the bottom directly.

3. Let fuel overflow into gallery.

4. Once cup is full, allow 30 seconds before releasing finger (fuel

relaxation time).

5. Release finger at 30 second mark, recovering fuel in beaker beneath

hole. Let the cup drain for another 30 seconds.

6. Again at the 30 second mark, simultaneously slide graduated cylinder

in place of beaker, collect for another 30 seconds then remove

graduated cylinder and replace beaker.

7. Discard collected material and repeat cleaning procedure.

4

E-1