D.T. Shouse and C. Neuroth

Air Force Research Laboratory, Wright-Patterson Air Force Base, Dayton, Ohio

R.C. Hendricks

Glenn Research Center, Cleveland, Ohio

A. Lynch, C.W. Frayne, J.S. Stutrud, E. Corporan, and Capt. T. Hankins

Air Force Research Laboratory, Wright-Patterson Air Force Base, Dayton, Ohio

Alternate-Fueled Combustor-Sector Performance

Part A: Combustor Performance

Part B: Combustor Emissions

NASA/TM—2012-217128

July 2012
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D.T. Shouse and C. Neuroth

Air Force Research Laboratory, Wright-Patterson Air Force Base, Dayton, Ohio

R.C. Hendricks

Glenn Research Center, Cleveland, Ohio

A. Lynch, C.W. Frayne, J.S. Stutrud, E. Corporan, and Capt. T. Hankins

Air Force Research Laboratory, Wright-Patterson Air Force Base, Dayton, Ohio

Alternate-Fueled Combustor-Sector Performance

Part A: Combustor Performance

Part B: Combustor Emissions

NASA/TM—2012-217128

July 2012

National Aeronautics and

Space Administration

Glenn Research Center

Cleveland, Ohio 44135
Available from

NASA Center for Aerospace Information

7115 Standard Drive

Hanover, MD 21076–1320

National Technical Information Service

5301 Shawnee Road

Alexandria, VA 22312

Available electronically at http://www.sti.nasa.gov

This work was sponsored by the Fundamental Aeronautics Program 

at the NASA Glenn Research Center.

Level of Review: This material has been technically reviewed by technical management. 
NASA/TM—2012-217128 1 

Alternate-Fueled Combustor-Sector Performance 

Part A: Combustor Performance 

Part B: Combustor Emissions 

D.T. Shouse and C. Neuroth 

Air Force Research Laboratory 

Wright-Patterson Air Force Base 

Dayton, Ohio 45433 

R.C. Hendricks 

National Aeronautics and Space Administration 

Glenn Research Center 

Cleveland, Ohio 44135 

A. Lynch, C.W. Frayne, J.S. Stutrud, E. Corporan, and Capt. T. Hankins 

Air Force Research Laboratory 

Wright-Patterson Air Force Base 

Dayton, Ohio 45433 

Abstract 

Alternate aviation fuels for military or commercial use are required to satisfy MIL-DTL83133F(2008) or ASTM D 7566 (2010) standards, respectively, and are classified as “drop-in” fuel 

replacements. To satisfy legacy issues, blends to 50% alternate fuel with petroleum fuels are certified 

individually on the basis of processing and assumed to be feedstock agnostic. Adherence to alternate fuels 

and fuel blends requires “smart fueling systems” or advanced fuel-flexible systems, including combustors 

and engines, without significant sacrifice in performance or emissions requirements. This paper provides 

preliminary performance (Part A) and emissions and particulates (Part B) combustor sector data. The data 

are for nominal inlet conditions at 225 psia and 800 F (1.551 MPa and 700 K), for synthetic-paraffinickerosene- (SPK-) type (Fisher-Tropsch (FT)) fuel and blends with JP-8+100 relative to JP-8+100 as 

baseline fueling. Assessments are made of the change in combustor efficiency, wall temperatures, 

emissions, and luminosity with SPK of 0%, 50%, and 100% fueling composition at 3% combustor 

pressure drop. The performance results (Part A) indicate no quantifiable differences in combustor 

efficiency, a general trend to lower liner and higher core flow temperatures with increased FT fuel 

blends. In general, emissions data (Part B) show little differences, but with percent increase in FT-SPKtype fueling, particulate emissions and wall temperatures are less than with baseline JP-8. High-speed 

photography illustrates both luminosity and combustor dynamic flame characteristics. 

Introduction 

Synthetic and biomass fueling are now considered as near-term aviation alternate fueling. The major 

impediment is a secure sustainable supply of these fuels at reasonable cost. Alternate aviation fuels are 

currently required to satisfy MIL-DTL-83133F (2008) for Fisher-Tropsch- (FT-) equivalent processed 

ASTM D 7566 (2010) and known as “drop-in” fuel replacements (military and civil, respectively). As in 

aviation, many land-based and marine power generation systems are elderly, known as the legacy issue. 

Fueling these systems requires careful compliance to the fuel handling and engine systems for which they 

were (are) designed. To satisfy a sustainable fuel supply, it will be necessary to accept fuels derived from 

a variety of feedstocks. Consequently, adherence to alternate fuels and fuel blends requires “smart fueling 
NASA/TM—2012-217128 2 

systems” or advanced fuel-flexible systems, including combustors and engines, without significant 

sacrifice in performance or emissions requirements. 

The common military services fueling concept is that JP-8+100 or alternate FT-type fuels that can 

fuel gas turbines as well as many diesel systems. Diesel biomass-derived oils are often unsuitable because 

sufficient aromatics and sulfur are lacking, which provide lubricity, thus reducing design component life. 

To counter these issues, additives are promoted. 

This paper provides preliminary performance, luminosity, emissions, and particulates combustor 

sector data relative to JP-8+100 as baseline fueling, for synthetic-parafinic-kerosene- (SPK-) type fuel 

blends (herein FT-type fuel) and projections for testing of biofuel fuel blends leading to preliminary 

development of smart fueling (fuel flexible) and combustor systems for the next generation aeronautic 

and aeronautic-derivative gas turbine engines. Fuel flexibility is an engine operations goal to enable 

various designer fuels operations with minor alterations in controller function or geometry. 

Truly performance and emissions are coupled issues; however, combustor performance will be 

presented in Part A and combustor emissions as Part B for understanding both in sufficient detail. 

Herein, fueling acronyms are synthetic paraffinic kerosene (SPK), and hydro-treated renewable jet (HRJ) 

also known as bio-SPK or SPK-HEFA (SPK from hydroprocessed esters and fatty acids) and proposed as 

ASTM D7566-Annex-1.

Part A: Combustor Performance 

Part A presents fueling characteristics, facility development, and operation followed by thermal 

performance of the combustor and combustor visualization. The results are for one of several 

combustors—herein denoted as combustor A—to be evaluated in development of fuel-flexible engine 

combustors. 

Most data herein are testing at nominal inlet conditions of 225 psia and 800 F (1.55 MPa, 700 K) at 

3% combustor pressure drop, where JP-8+100 (JP-8) is taken as baseline. Selected emissions data are 

provided at and below 225 psia (1.55 MPa). 

Fuel Characteristics 

In general all alternate fueling is required to meet or exceed MIL-DTL-83133F or ASTM D7566 and 

Annex 1 requirements. The carbon-distribution for each fuel used and primary characteristics differ 

depending on feedstock source and distilling practices, yet all fall within specification. Typical Cdistributions for JP-8 and an (SPK) FT-derived fuel are shown in Figure 1(a) with vendor variations in 

fuels illustrated in Figure 1(b). Secondary refining of petroleum-based kerosene fuels can also satisfy 

specifications. 

The specifications for one of the fuels, AFRL No. 5172 Shell GTL-SPK (FT), are presented in 

Appendix A. 

While fuels purchased by Defense Energy Support Center (DESC) are within specification, 

independent of whether petroleum- or alternate-based fuels, batch-to-batch variations do occur depending 

on processors, feedstock, ;production date and location of fuel production: a world-wide fuels sourcing 

problem. 
NASA/TM

The g

reported i

will not b

Research 

Altho

those of R

blending h

test fuel to

M—2012-21712

F

F

general descrip

n Hendricks e

e discussed h

Laboratory (A

ough some gen

References 1 a

had to be mad

o the facility 

28 

Figure 1(a).—R

No. 5172 FT

and 0% sulfu

Figure 1(b).— V

proposed alt

Combu

ption of the c

et al. (Ref. 1)

herein. Details

AFRL) are pr

neral aspects 

and 2, specifi

de, including 

fuel pumps, f

Representative 

T (SPK) from S

ur. The JP-8 cit

Variations in re

ternate fuels wi

ustor and F

combustor and

. The particu

s of the High 

rovided by Sh

of the fuel de

c facility mod

remote altern

flow meters, a

3 

carbon distribu

hell gas-to-liqu

ted is 19% aro

epresentative c

ith high and low

Facility C

d supporting r

ular aspects of

Pressure Com

house et al. (R

elivery system

difications an

nate test fuel s

and control sy

utions for JP-8

uid (GTL) with 0

matics and 120

carbon distribut

w n-paraffinic t

haracteris

research cell 

f the geometr

mbustion Rese

Ref. 2). 

m and operatio

nd increased c

storage/tanka

ystems (see A

8 and AFRL 

0% aromatics 

00 ppm sulfur. 

tions for 

to isomer ratios

stics 

data are simil

ry tested are p

earch Facility

ons of the fac

capability to h

age and delive

Appendix B). 

s. 

lar to those 

proprietary an

y at the Air Fo

cility are simi

handle fuel 

ery of the alte

nd 

orce 

lar to 

ernate 
NASA/TM—2012-217128 4 

Facility Development 

Before validation data could be taken, it was necessary to learn what it takes to conduct high-pressure 

combustor testing of alternate fuels such as FT and biomass feedstock fuels. It is first necessary to 

establish the combustion parameters required by the study such as operability, performance, durability 

time-dependent measurements such as flame studies, and others. Next, an assessment of the effects of 

pressure ratios and inlet temperatures on both the combustor sector model and desired data was 

undertaken as well as most importantly, how to safely blend the fuels. The blending system, while 

complex, enables operations to establish and stabilize combustor inlet pressures and temperatures of 

preheated air at the required test condition without the additional complication of simultaneously 

establishing fuel blend. 

To establish the fuel delivery system, questions such as how much fuel and time are required to fully 

evaluate a typical fuel candidate must be resolved. A 500-gal trailer-mounted fuel tank was chosen for 

porting alternative fuels with the added feature of coupling to the facility fueling system. The facility has 

two duplicate fuel systems that provided a means of handling JP-8 fuel with one system to pump, meter, 

and control the JP-8 fuel; this system is referred to as the main fuel delivery system. The identical system 

was fed the alternative fuel supply, which is pumped from the trailer into the facility primary fuel system 

and ultimately blended online with the main fuel system to provide the desired fuel blend from 0% to 

100% trailer fuel. An analysis of fuel blending errors is provided in Appendix C. To verify the 50/50 

blend, samples were collected just upstream of the fuel injectors and analyzed using liquid 

chromatography; blending is within ±4%. 

Test Parameters and Data Collection 

For this series of testing, the nominal test conditions for pressures and temperatures of blends and the 

extensive data collection systems have been established. The parameters were chosen to be most 

representative of engine operations envelope from idle to altitude cruise; however, TO (take-off) pressures 

are currently beyond the range of this facility. 

Combustor parameters 

Inlet pressures (P): 75, 125, 175, and 225 psia (0.517, 0.862, 1.207, and 1.551 MPa) 

Inlet temperature (T): 500, 625, 725, and 790 F (533, 603, 658, and 694 K) 

Combustor pressure drops (ΔP): 3%, 4%, and 5% 

Fuel blends: 100% JP-8, 50:50 JP-8:FT, and 100% FT 

Data collection 

Gaseous emissions 

Exit temperature rake type B thermocouples, (also for metal and sidewall temperatures) 

Photo diode output (voltage) 

Still and high-speed photography

Smoke and particulate emissions 

Combustor outer and inner liner temperature data are given in Appendix D, and estimates of errors in 

performance, flame temperature, emissions data, and geometric coordinates are given in Appendix C. 

Combustor Thermal Performance 

The combustion efficiencies for combinations of fuel:air ratio F/A and fuel compositions were of the 

order of 99.9% (Table 1), and one is unable to distinguish combustor changes from this single parameter; 

thus, other parameters will be investigated. For example, the emissions-based calculated flame 

 
NASA/TM

temperatu

further in 

 Lean 

observatio

testing. F

F/A for bo

with some

No fu

definitive

M—2012-21712

ure (Fig. 2), in

the next secti

blow out (LB

ons made dur

For a limited d

oth 100% FT 

LBO1

LBOJ

(F/A)

e sensitivity t

IGNF

IGNJP

(F/A)

urther tests we

. Systematic a

28 

TABLE 1.—

WITH F/A

INLET CO

(700 K) W

F/A 

0.010 

0.015 

0.020 

0.025 

a

Letters refe

F

ncreases with 

ion. 

BO) and igniti

ing startup an

data set at a n

and JP8+100

100% FT = 0.00

JP-8+100 = 0.00

) LBO 100% FT /(F

o percent com

T = 0.01

P-8+100 = 0.01

)IGN 100% FT /(F/

ere undertaken

altitude restar

—VARIATION

A AND FUELIN

ONDITIONS AT

WITH JP-8 +10

PRESS

JP-8 +100

F 

99.89 

O 

99.93 

Q 

99.94 

er to proprietar

Figure 2.—Calc

variation with

F/A, with FT

ion (IGN) tes

nd shutdown p

ominal 5% co

0. The averag

038 ± 0.0004

043 ± 0.0004

F/A) LBO JP-8+10

mbustor press

10 ± 0.004 

13 ± 0.007 

/A)IGN JP-8+100

n, and data at

rt, ignition, an

5 

NS IN COMBUS

NG COMPOSITI

T 225 PSIA (1.55

00 AS BASELIN

SURE DROP ~3

JP-8:FT 50

H 

99.9 

K 

99.94 

U 

99.94 

ry data reductio

culated flame te

 F/A and fuel c

T about ΔT = 

sts were not p

procedures w

ombustor pre

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4 

4

00 < 1 

ure drop. The

 < 1 

t lower combu

nd LBO studi

TOR EFFICIEN

ION FOR NOMI

51 MPA) AND 8

NE.a COMBUST

% 

0:50 blend 

on parameters.

emperature 

composition. 

70 F (39 K)

part of the plan

were consisten

ssure drop, L

values are 

e average igni

ustor pressure

ies are yet to b

NCIES 

INAL 

800 F 

TOR 

FT 

G 

99.91 

M 

99.91 

T 

99.95 

) higher. This 

nned test prog

nt with previo

LBO is nearly 

ition F/A valu

e drops were 

be conducted

will be discu

gram, yet 

ous JP-8+100 

40% of the (I

ues are 

insufficient to

d. 

ussed 

IGN) 

o be 
NASA/TM

The c

pressure d

noted that

The li

as sidewa

For al

FT, and bl

Sidewalls

Figur

fuel blend

axial posi

Unwrapp

Figur

0.015, and

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to JP-8+1

liner surfa

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Figur

to the left 

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Figur

the left of

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Figur

outer liner

temperatu

M—2012-21712

combustor wa

drop measurem

t no inconsist

iner and wall 

all or liner (i.e

ll figures here

lended 50% J

s 

e 3 illustrates

d composition

tion of the the

ped Combust

es 4(a), (b), a

d 0.020) and t

(largest) and m

00 are provid

ace circumfer

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e 4(a) illustra

of the peak a

r the FT fuelin

e 4(b) represe

f the peak and

eling. 

e 4(c) represe

r temperature

ures are lower

Fig

28 

Sur

alls and liners 

ments are sen

ent pressure m

surface temp

e., facing insid

ein, fuel comp

JP-8+100 and

s that sidewall

n JP-8, FT, an

ermocouple. 

tor Liner 

and (c) represe

three fueling 

maximum inn

ded in Append

rence ( 0 to 1

ates the unwra

and inner line

ng. 

ents unwrappe

d inner liner te

ents the unwra

es to the left o

r for the FT fu

gure 3.—Sidew

rface Ther

were instrum

nsitive inform

measurements

perature locati

de or outside)

positions are d

d 50% FT by v

l temperature

nd 50:50. FWD

ent unwrappe

compositions

ner liner temp

dix B. We use

) to normaliz

apped liner te

r temperature

ed liner temp

emperatures t

apped liner te

of the peak an

ueling. 

wall temperatur

6 

rmal Meas

mented for pre

mation and wil

s were found.

ions are sensi

). 

denoted as fo

volume is 50:

s (TSW) stro

D represents f

ed liner surfac

s (JP-8, FT, an

peratures, resp

e the term “un

ed inner liner

mperatures fo

es to the right

eratures for F

to the right of

emperatures f

nd inner liner 

e variation with

surements

essure and tem

ll not be prese

. 

itive informat

ollows: JP-8+

:50. 

ngly depend 

forward; MID

ce temperatur

nd 50:50). Th

pectively. Tem

nwrapped” to

r circumferen

or F/A = 0.01

t of the peak. 

F/A = 0.015 w

f the peak. Th

for F/A = 0.02

temperatures 

h F/A and fuel c

s

mperature. In 

ented as such

tion and temp

100 is JP-8, F

on F/A and w

D, middle; and

res for three F

he twin peaks

mperature diff

o mean the no

ntial surface (1

0 with outer l

The temperat

with outer line

he temperature

20 (JP-8) and 

 to the right o

composition. 

general the 

h. It should be

peratures are n

Fischer-Trops

weakly depend

d AFT, the af

F/A values (0.

s represent 

ferences base

ormalized out

1 to 2) as a 

liner tempera

tures are sligh

er temperature

es are lower f

0.019 (FT) w

of the peak. T

e

noted 

sch is 

d on 

ft 

.010, 

lined 

side 

atures 

htly 

es to 

for 

with 

The 
NASA/TM

Figure 4(a).—

0.010 and

Normalize

0 to 1 out

M—2012-21712

—Unwrapped 

d fueling compo

ed combustor l

ter and 1 to 2 in

28 

liner temperatu

ositions JP-8 a

iner thermocou

nner. 

Figure 4(c

and fue

combu

1 to 2 i

ures for F/A = 

and FT. 

uple locations: 

c).—Unwrappe

eling compositi

stor liner therm

inner. 

7 

Figur

0.0

No

0 to

ed liner temper

ions JP-8 and F

mocouple locati

re 4(b).—Unwra

015 and fueling

ormalized comb

o 1 outer and 1

ratures for F/A 

FT. Normalized

ions: 0 to 1 out

apped liner tem

g compositions 

bustor liner the

1 to 2 inner. 

~0.020 

d

ter and 

mperatures for 

 JP-8 and FT. 

ermocouple loca

F/A = 

tions: 
NASA/TM

Figur

JP-8+100

(JP-8, FT,

Figur

compositi

inner. JPhigher for

Figur

compositi

inner. JPtemperatu

fueling; a

M—2012-21712

es 5(a), (b), a

as baseline, f

, and 50:50). 

e 5(a) represe

ions 50:50 an

8 difference i

r FT and blen

e 5(b) represe

ions JP-8 and

8 difference i

ures are nomin

ctual differen

Figure

F/A

line

Figure 5

F/A =

therm

28 

and (c) represe

for three F/A 

ents the unwra

d FT. Norma

is 0. On avera

ded fueling th

ents the unwr

 FT. Normali

is 0. On avera

nally 20 °F (

nces are given

e 5(a).—Unwra

= 0.010 and fu

r thermocouple

5(b).—Unwrap

= 0.015 and fue

mocouple locat

ent unwrappe

values (0.010

apped liner di

lized combus

age, the unwra

han for JP-8 f

apped liner d

ized combusto

age, compared

11 °C) lower 

n in Appendix

pped liner tem

ueling composi

e locations: 0 to

pped liner temp

eling compositi

tions: 0 to 1 out

8 

ed liner surfac

0, 0.015, and 

ifferences [Tf

stor liner therm

apped liner te

fueling, with a

ifferences [Tf

or liner therm

d with JP-8+1

for FT fuelin

x B. 

perature differe

itions 50:50 an

o 1 outer and 1

erature differen

ions JP-8 and F

ter and 1 to 2 i

ce temperatur

0.020) and th

fuel blend – TJP-8

mocouple loc

emperatures a

actual differe

fuel blend – TJP-8

mocouple loca

100 fueling, th

ng and 14 °F 

ences T (Tfuel

d FT. Normaliz

1 to 2 inner. JP

nces T (Tfuel b

FT. Normalized

nner. JP-8 diffe

res difference

hree fueling c

] for F/A = 0

cations: 0 to 1

are nominally

ences given in

8] for F/A = 0

ations: 0 to 1 o

the unwrapped

(8 °C) lower 

 blend – TJP-8) fo

zed combustor 

P-8 difference is

blend – TJP-8) for

d combustor lin

erence is 0. 

s relative to 

compositions 

0.010 and fue

1 outer and 1 t

y 10 °F (6 °C

n Appendix B

0.015 and fue

outer and 1 to

d liner 

for 50:50 ble

or 

s 0. 

r

ner 

ling 

to 2 

) 

B. 

eling 

o 2 

ended 
NASA/TM

Figur

~0.020 an

1 outer an

unwrappe

for blende

Figur

100% JPM—2012-21712

e 5(c) represe

nd fueling com

nd 1 to 2 inner

ed liner tempe

ed fueling; se

e 6 shows tha

8 to 100% FT

Figure 5

~0.02

therm

28 

ents the unwra

mpositions 50

r. JP-8 differe

eratures are no

e differences 

at peak inner l

T. 

(c).—Unwrapp

0 and fueling c

ocouple locatio

Figu

a

apped liner te

0:50 and FT. 

ence is 0. On

ominally 45 °

given in App

liner tempera

ped liner tempe

compositions 50

ons: 0 to 1 oute

ure 6.—Peak in

at normalized lo

9 

emperatures d

Normalized c

n average, com

°F (25 °C) lo

pendix B. 

atures are near

rature differenc

0:50 and FT. N

er and 1 to 2 in

nner liner temp

ocation 1.5. 

differences [T

combustor lin

mpared with J

ower for FT fu

rly independe

ces T (Tfuel ble

Normalized com

ner. JP-8 diffe

peratures (TIL) 

Tfuel blend – TJP-8

ner thermocou

JP-8+100 fue

ueling and 18

ent of fueling 

end – TJP-8) for F

mbustor liner 

rence is 0. 

8] (F) for F/

uple locations

ling, the 

° F (10 °C) l

composition 

F/A 

/A 

s: 0 to 

lower 

from 
NASA/TM

Elimi

temperatu

combusto

tion. Thro

not to imp

Figure

M—2012-21712

nating the sid

ures. Omitting

r liner axial a

oughout, the i

ply the author

e 7(a).—Comb

28 

Co

dewall peak te

g the peak tem

and circumfer

individual dat

rs know or un

bustor liner inne

ombustor In

emperature al

mperature, Fig

rential surface

ta points are c

nderstand the 

er surface temp

10 

nner and Ou

llows visualiz

gures 7(a) thr

e temperature

connected by

physical proc

perature variati

uter Liner

zation of the s

rough 7(f) illu

e variations w

y continuous c

cesses occurri

ions with fuelin

smaller chang

ustrate major p

with F/A and fu

curves for eas

ing between d

ng composition 

ges in surface 

portions of th

fueling compo

se of compari

data points. 

at F/A = 0.010

he

osison, 

0. 
NASA/TM

Figur

with temp

Figures 5(

compositi

than for JP

for fueling

slightly hi

Figure

M—2012-21712

es 7(a) and (b

perature differ

(a), (b), and (

ion changes fr

P-8 fueling. F

g composition

igher than for

e 7(b).—Comb

28 

b) illustrate va

rences baselin

c). Figure 7(a

from JP-8 to F

Figure 7(b) sh

n changes fro

r JP-8 fueling

bustor liner oute

ariations of co

ned to JP-8+1

a) shows inne

FT. The tempe

hows variation

om JP-8 to FT

g. 

er surface temp

11 

ombustor axia

100 in Append

er liner temper

eratures for F

ns of outer lin

T. The tempera

perature variati

al and circum

dix B, with di

ratures at F/A

FT and blende

ner combustio

atures for FT 

ions with fuelin

mferential surf

istribution illu

A = 0.010 for 

ed fueling are 

ons temperatu

and blended 

ng composition

face temperat

ustrated in 

fueling 

slightly high

ures at F/A = 

fueling are 

 at F/A = 0.010

tures 

her 

0.010 

0. 
NASA/TM

Figur

compositi

temperatu

Figur

compositi

at F/A ~0.

F

M—2012-21712

e 7(c) shows 

ion changes fr

ures at F/A = 0

e 7(e) shows 

ion changes fr

.020 for fuelin

igure 7(c).—Co

28 

variations of 

from JP-8 to F

0.015 for fuel

variations of 

from JP-8 to F

ng compositio

ombustor oute

combustor ou

FT. Figure 7(d

ling composit

combustor in

FT. Figure 7(f

on changes fr

r liner tempera

12 

uter liner tem

d) illustrates v

tion changes f

nner liner tem

f) shows varia

rom JP-8 to F

ture variations 

mperatures at F

variations of c

from JP-8 to 

mperatures at F

ations of com

FT. 

with fueling co

F/A = 0.015 f

combustor inn

FT. 

F/A ~0.020 fo

mbustor outer l

omposition at F

for fueling 

ner liner 

or fueling 

liner tempera

F/A = 0.015. 

tures 
NASA/TM

F

M—2012-21712

Figure 7(d).—C

8 

ombustor inner liner tempera

13 

ture variations with fueling composition at F/A = 0.015. 
NASA/TM

F

—2012-21712

Figure 7(e).—C

8 

ombustor inner liner tempera

14 

ature variations with fueling composition at F/A ~0.020. 
NASA/TM

F

M—2012-21712

igure 7(f).—Co

8 

mbustor outer liner tempera

15 

ture variationswith fueling composition at F/A ~0.020. 
NASA/TM

In the

based on e

the exhau

Three

monitor th

set of test 

to its loss 

was hotter

> tempera

Figure 8. 

linear locu

higher tha

which is h

emissions

efficiencie

and comp

part of ha

50:50 loci

0.015, imp

unwarrant

M—2012-21712

e combustor th

emissions wa

ust plane. 

e type-B meta

he combustor

runs, restrict

to corroborat

r at the top th

ature (M) > te

 While dange

us fit to the S

an for JP8+10

higher but in r

s. The signific

es, and (2) co

ponent life can

ving sparse d

i to be convex

plying cross-o

ted but dange

Figur

fun

28 

Combu

hermal perfor

as higher than

al thermocoup

r exhaust. The

ting interpreta

te trends base

han the bottom

emperature (B

erous to draw 

PK-FT and JP

00. With near

reasonable ag

cance is twofo

omponent life 

n vary as muc

data is making

x, whereas the

over points. D

erous. 

re 8.—Variation

nction of fuel:ai

stion Exha

rmance sectio

n that of JP8+

ples formed a 

e top thermoc

ation of exit p

ed on solely o

m which affec

B) with consis

hard conclus

P8+100 data 

rly equivalent

greement with

old: (1) highe

decreases. P

ch as 25% wit

g assumptions

e JP8+100 loc

Drawing impl

n of exhaust plu

ir ratio (F/A). 

16 

aust Rake

on, we noted t

100 (Fig. 2). 

thermal rake

couple was da

plane tempera

on the average

cts the turbine

stent trends fo

sions from spa

show the SPK

t slopes, the in

h the calculate

er turbine inle

Pattern factor

th a 10 °C cha

s about the tre

cus is concav

lications outsi

ume temperatu

e Tempera

that the SPK-

 We now look

, [top (T), mi

amaged by the

atures, yet eno

e of M and B 

e inlet pattern 

or percent fue

arse data sets,

K-FT exhaust

ntercepts diff

ed flame temp

et temperature

rs are very im

ange in tempe

ending. Figur

ve with a pote

ide the 0.01 ≤

ures with perce

ature 

-FT calculated

k at measured

idplane (M), b

e exhaust plum

ough data wer

readings. The

n factor. Herei

eling as functi

, the trends ar

t temperature 

fer close to 88

perature (Fig.

es provide hig

mportant to tur

erature. The t

re 9 shows the

ential optimum

≤ F/A < 0.02 d

ent fueling as a

d temperature

d temperature

bottom (B)] to

me after an in

re gathered pr

e exhaust plu

in, temperatur

ion of F/A, 

re instructive

to be signific

8 °F (49 °C), 

. 2), based on

gher engine 

rbine efficienc

third dangerou

e both the FT 

m near F/A = 

data set is not

a

e

es in 

o

nitial 

rior 

ume 

re (T) 

. The 

cantly 

n

cy 

us 

and 

t only 
NASA/TM

Digita

insights fo

combusto

Figure 10

increased 

Highshows seq

frames rel

thermocou

producing

temperatu

photo dio

M—2012-21712

Figur

as 

al camera exp

or computatio

r designers: f

(a), the digita

percent JP-8+

-speed video a

quences from 

late to 100% 

uple rake mea

g higher calcu

ures. These o

de as well as 

28 

re 9.—Curvatur

a function of fu

posures and h

onal fluid dyn

for example, l

al camera pict

+100 and F/A

at 20 kfps illu

that video). T

FT fueling at

asurements in

ulated and me

bservations a

pictures and h

re of exhaust p

uel:air ratio (F/A

Combusti

igh-speed pho

namics (CFD)

luminosity va

tures for F/A 

A. 

ustrates the na

The upper fra

t two different

ndicate that FT

easured flame 

are backed up 

high-speed vi

17 

plume temperat

A). 

ion Visual

otographs of 

) analysts (Re

ariation with F

= 0.020. The

ature of the un

ames relate to 

t fuel:air ratio

T fuels have h

temperatures

qualitatively

ideo movies p

ture loci with p

lization 

the combusti

ef. 3) as well a

FT versus JPe general tren

nsteady comb

JP-8+100 fue

os (F/A). Bot

higher heatin

s at the combu

y by observati

providing visu

ercent fueling 

on process pr

as heuristic in

-8 concentrati

nd is increased

bustion proce

eling (0% FT

th emissions a

ng values than

ustor exit, yet

on of flame lu

ual observatio

rovide some 

nformation fo

ion as illustra

d luminosity w

sses (Figure 1

T), and the low

and exit-plan

n JP-8+100, 

t with lower l

uminosity usi

ons.

or 

ated in 

with 

10(b) 

wer 

e 

liner 

ing a 
NASA/TM

(a) Digi

(b) High-sp

Figure 10.

Altern

particulate

as baselin

developm

and aeron

but propri

blend of 5

The te

varied ove

800 F (1

results: 

1

2

M—2012-21712

ital camera pho

peed video seq

.—Combustor A

nate fueling te

es combustor

ne fueling, and

ment of smart f

nautic-derivati

ietary combus

50% each by v

est data prese

er a range of v

.551 MPa and

. Combustor p

100% FT are

. Both outer a

a. 

b. 

c. 

28 

otographs illust

uences compar

A experiment p

esting is bein

r sector data fo

d to make pro

fueling (fuel f

ive gas turbin

stor are provi

volume.

ented are part 

values. The d

d 700 K), and

performance 

e nearly ident

and inner wall

warmer at F

cooler at F/

cooler at F/

trating changes

ring JP-8+100 fu

photographs illu

Conclu

g carried out 

for SPK-type 

ojections for t

flexible) and 

ne engines. He

ded for JP-8+

of a more ext

data herein are

d JP-8+100 is 

efficiencies a

tical at about 

l temperature

F/A = 0.010 b

/A = 0.015 by

/A = 0.02 (0.0

18 

s in flame struc

ueling to FT fue

ustrating chang

usions: Par

to determine 

(e.g., Fischer

testing of biof

combustor sy

erein alternate

+100 and a Fi

tensive data s

e for the case 

taken as base

at 0% FT (JP99.9%. 

es, on average

by 10 °F (6 °

y 20 °F (11 °C

019) by 45 °F

cture with chan

eling combustion

ges in flame st

rt A 

preliminary p

r-Tropsch) fue

fuel fuel blen

ystems for the

e fueling test 

ischer-Tropsc

set where com

of nominal in

eline. These d

-8), at 50% bl

e, run 

C) with FT fu

C) with FT fu

F (25 °C) with

nges in fuel ble

n at two differen

tructure with ch

performance,

el blends, rela

ds leading to 

e next generat

results for a 

ch- (FT-) deriv

mbustion para

nlet condition

data provide t

lended FT and

ueling 

ueling 

h FT fueling 

nd at F/A= 0.02

nt fuel:air ratios 

hanges in fuel b

 emissions, an

ative to JP-8+

preliminary 

tion aeronaut

well-characte

ved fuel and a

ameters were 

ns at 225 psia

the following 

d JP-8, and at

20. 

(F/A). 

blend. 

nd 

+100 

ic 

erized 

a

a and 

t
NASA/TM—2012-217128 19 

3. Sidewall temperature TSWFD ranges are 5.6% , 2.1%, and 1.4% higher for FT fueling for 

F/A = 0.01, 0.015, and 0.02, respectively. This may relate to the flame front moving away from 

the fuel injection interface. 

4. Rake temperatures show core flow generally higher with FT than with JP-8, but one rake 

thermocouple (TC) was lost during testing, which inhibits conclusiveness. 

5. All temperatures increase with F/A. 

6. The 50:50 blend test results generally are between JP-8 and FT and somewhat closer to FT. 

7. Lean blow out (LBO) and ignition (IGN) tests were not part of the planned test program, yet 

observations made during startup and shutdown procedures were consistent with previous 

JP-8+100 testing. For a limited data set at a nominal 5% combustor pressure drop, the F/A 

for LBO is nearly 40% of the IGN F/A for both 100% FT and JP-8+100. On the average, 

(F/A) LBO 100% FT /(F/A) LBO JP-8+100 < 1, with some sensitivity to percent combustor pressure 

drop, and (F/A) IGN 100% FT /(F/A) IGN JP-8+100 < 1. Definitive values at lower percent combustor 

pressure drops are insufficient for conclusions. 

8. Altitude relight, ignition and LBO testing programs remain to be carried out. 

9. High-speed photographs of the combustion process provide some insights for CFD analysts as 

well as heuristic information for combustor designers. For example, there was decreased 

luminosity with FT versus JP-8, and clips show enhanced vorticity for the conditions cited in 

Table 1. 

Part B: Combustor Emissions 

Part B presents gaseous emissions as CO2, CO, and NOx (which also includes smoke and luminosity 

data); particulate emissions including distribution; and a brief comparison to small and large engine 

testing results from other programs. The emissions data are taken for the same tests and test conditions 

cited in Part A, nominally 225 psia at 800 F (1.551 MPa at 700 K) with the sampling probe located at 

the nozzle exit plane. Emissions have a direct impact on aviation climatic constraints based on life cycle 

analysis (LCA) of fueling feedstocks, which includes fueling development and engine emissions. Herein 

the testing is directed toward fuel flex engine combustors, providing basic data for LCA fueling 

evaluations, where combustor A is one of several to be evaluated in development of fuel-flexible engine 

combustors. 

Gaseous Emissions 

Measurements for NOx were determined from combining NO and NO2 measurements (Figs. 11(a) 

and (b). Nitric oxide (NO) with molecular atomic dimension (0.115 nm) (NO), while less than JP-8 at 

F/A = 0.010, steadily increases to become marginally higher than JP-8 at F/A = 0.020 (extrapolated) 

(Fig. 11(a)). Nitrogen dioxide (NO2) (0.221 nm) (ppm) for FT or 50:50 blended fueling is considerably 

higher than for JP-8 and generally increases with F/A. Combining nitrogen dioxide (ppm) and nitric oxide 

(ppm), the trend with F/A and fuel composition is similar to that seen for NO; a slight decrease in NO2: 

less than JP-8 at F/A = 0.010 and marginally higher than JP-8 at F/A = 0.020 (Fig. 11(c)). 

Regarding the variation of %CO2 (0.0116 nm), ppm CO, and %O2, (Figs.12, 13, and 14, respectively), 

whereas each is strongly dependent with increasing F/A, the increase in %CO2 and ppm CO and the 

decrease in %O2 are marginally consistent with varied dependencies on fuel composition. The %CO2

appears somewhat consistent with decreased %CO and O2 with fueling changes from JP-8 to FT, in 

agreement with flame temperature (Fig. 2). 

 
NASA/TM

Figure

var

[(g/kg) [E

[(g/kg) [E

[(g/kg) [E

Aerospace

EIZ  [103

 10

mX = mas

 of

[(g/kg) [ E

[NOx] [C

m

 F

M—2012-21712

e 11(a).—Nitric

riations with F/A

EINOx or KHN

EINOx or KHN

EINOx or KHN

e recommend

3

mZ/mf ]  [m

03/103  10-6 p

ss flow rate of

f X, and FAR

EINOx ] SAE

CO] [CO2] [

mass, α = ratio

igures 11(a) a

28 

c oxide emissio

A and fueling c

Figu

w

NOx]  (ppm

NOx]  (ppm

NOx]  (ppm

ded practice (a

mf (1+FAR–1)/

ppm 

f X (g/s), mf

R = fuel:air rat

E ARP 1533 ~

[CxHy ] = ma

o of H/C = n/m

and 11(b) 

Figu

fu

on (ppm) 

composition. 

ure 11(c).—NO

with F/A and fue

m NOx) (1 + F

m NOx) (1 + F

m NOx) (1 + F

arp) and (arpc

/m gas products ] 

= mass flow r

tio F/A 

~ ({[NOx]/([C

ss fractions o

m in fuel CmH

ure 12.—Variat

uel composition

20 

Figu

va

Ox emission va

eling compositi

FAR)/(630 FA

FAR)/(715 FA

FAR)/(655 FA

c) corrected a

 [molZ MZ/m

rate of fuel (k

CO]+[CO2] + 

of NOx, CO, C

Hn where NOx

tion of %CO2 w

n. 

ure 11(b).—Nitr

ariations with F

riations (ppm) 

ion. 

AR)]. FAR = 

AR)]. FAR = 

AR)]. FAR = 

arp 

mZ ]  [m gas p

kg/s), MX = m

[CxHy]}103

CO2, and tota

x mol mass is

with F/A and 

rogen dioxide e

F/A and fueling

fuel:air ratio 

fuel:air ratio 

fuel:air ratio 

products/(∑ molj

molar mass of

 MNOx /(MC +

al hydrocarbon

s assumed to b

emission (ppm

 composition.

F/A [2] 

F/A (herein, 

F/A (herein, 

 Mj) gas products]

f X , molX = m

+ αMH) 

n THC, M = m

be 46; contras

) 

arp) 

arpc) 

]  

moles 

molar 

st to 
NASA/TM

Figur

compositi

JP-8 to FT

changes a

consistent

combustio

The s

drawing a

the "non-s

the exhau

operating 

on fuel:air

known at 

of fuel co

F/A = 0.0

0.02, yet t

for either 

Smok

distributio

M—2012-21712

e 12 shows th

ion. However

T. Carbon mo

at F/A = 0.019

t with increas

on temperatur

moke number

a sample of ex

stained" and "

ust plane. Rep

conditions. T

r ratio F/A an

this time, nor

mposition be

10 (Fig. 16). 

they are nearl

JP-8 or 50:50

ke number and

on, compositi

28 

Figur

fue

(1

Figure 14.—

he strong vari

r, it appears so

onoxide (0.113

9, which extra

sing F/A—as 

res with more

Smo

r (SN) is dim

xhaust throug

"stained" pap

resentative av

The general tr

nd is less depe

r is it entirely

cause the smo

For FT fuelin

ly the same at

0 blended fue

d THC results

on, and toxic

re 13.—Variatio

el composition

+ FAR)/(1220 F

—Variation of %

ation of %CO

omewhat con

3 nm) (CO) g

apolated is un

well as highe

e complete co

oke and Ph

mensionless [(m

gh a filter pape

er. Smoke nu

verages are pr

rend of total h

endent on fue

y clear that for

oke data do sh

ng, the smoke

t F/A = 0.015

l. 

s reinforce the

ology. 

21 

on of CO (ppm

. [(g/kg) EICO 

FAR)]. FAR = f

%O2 with F/A a

O2 with F/A, b

sistent with d

generally is lo

nresolved (Fig

er rake temper

ombustion (Fi

hoto Diode

mg-C)/s / (kg

er, then comp

umber, NOx, C

rovided to cer

hydrocarbon e

l blend excep

r all intents an

how more dis

e number is w

. FT smoke n

e necessity fo

m) with F/A and 

 (ppm CO) 

fuel:air ratio F/A

and fuel compo

but it is nearly

decreased %O

ower with fuel

g.13). The dec

ratures—with

ig. 2). 

e Number

g-combustor g

paring the cha

CO, and HC m

rtificating aut

emissions (TH

pt with FT at F

nd purposes w

stinctive trend

well below tha

number increa

or good partic

A. 

osition. 

y independen

O2 with fueling

ling from JPcrease in %O

h FT, indicatin

rs 

gas)/s ]. It is m

ange in the ref

measurement

thorities at se

HC) (Fig. 15) 

F/A = 0.015. 

why THC is n

ds with fuelin

at of JP-8 at F

ases with F/A

culate measur

nt of fuel 

g changes fro

-8 to FT with 

2 (Fig. 14) is 

ng increased 

measured by 

flectance betw

s are all made

everal engine 

 strongly dep

The reason is

nearly indepen

ng compositio

F/A of 0.01 an

A, but it is not 

rements, their 

om 

some 

ween 

e in 

ends 

s not 

ndent 

on at 

nd 

clear 
NASA/TM—2012-21712

Figure

valu

fuel

drop

28 

Figure 15

with F/

THC) (

Figure

fue

e 17.—Variation

ues for 100% J

; (P,T)inlet is [75

p. Photo on left

5.—Total hydro

/A and fuel com

(1+ FAR)/(2070

e 16.—Smoke 

ling compositio

n in photo diod

P-8 and 100% 

5 psia (0.517 M

t is 100% JP-8

22 

ocarbon variatio

mposition. [(g/kg

0 FAR)]. FAR =

number variatio

on. 

e voltage outp

FT fueling as w

MPa), 500 °F (5

8 and on the rig

ons, THC (ppm

g) THC  (ppm

= fuel:air ratio F

ons with F/A a

ut with fuel ble

well as 50% bl

533 K)] at 3% c

ght 100% FT at

m) 

m

F/A. 

nd 

ending at variou

lend of JP-8 an

combustor pres

t F/A =0.010. 

us F/A 

nd FT 

ssure 
NASA/TM

Figur

fuel is var

(P,T)inlet (7

The in

Figure 18

values. Sm

fueling. A

characteri

as the fue

increases 

Figur

(1.207 to 

number an

corrobora

The p

and the ch

environm

To de

CO2-base

correspon

for FT and

Such evid

content of

M—2012-21712

[N

e 17 illustrate

ried. Optical a

75 psia (0.517

ncrease in fla

. The decline 

moke number

A striking featu

istic clean blu

l blend is incr

as well at hig

e 18 illustrate

1.551 MPa) (

nd photo diod

ate the particu

particulate dis

hemical natur

ental health h

monstrate the

d F/A values.

ndence wherea

d blends to be

dence may ref

f JP-8. 

28 

Figure 18.—

combus

1.551 M

reductio

(soot) a

Note: FT fuels 

es the change 

access window

7 MPa), 500 °

me luminosit

in smoke num

r consistently 

ure is the dec

ue flame at 10

reased to 100

gher F/A value

es a decrease 

(note the anom

de emissions w

ulate data show

tribution depe

re of the partic

hazards, cloud

e operability o

 The 100% F

as the 100% J

e consistently

flect the paraf

—Smoke numb

stor inlet pressu

MPa) at F/A = 0

ons in polycyclic

nd polycyclic a

have few if any

in flame lum

ws are combu

°F (533 K)) a

ty follows the

mber with inc

increases wit

crease in relati

00% FT fuelin

0% JP-8 sugge

es; the wall m

in smoke num

maly at 175 p

with increase

wn later. 

Particul

ends on engin

culates and th

d formations, 

of the emissio

T and 50:50 b

JP-8 is +8% t

y higher and J

ffinic nature o

23 

ber variations w

ures of 175 and

.020 and 0.025

c aromatic hyd

aromatic compo

y aromatics and

minosity on a r

ustor pressure

at 3% combus

e same trends 

creasing FT fu

th F/A indepe

ive flame lum

ng. This incre

ests that the ra

metal tempera

mber as comb

psia (1.207 MP

d F/A from 0

late Emiss

ne power setti

heir toxicity. S

and climatic 

ons probes, th

blends are wi

to –34% with 

JP-8 lower tha

of FT and the 

with %FT fuelin

d 225 psia (1.2

5. Results impl

drocarbons (PA

ounds (PAC). 

d lower total pa

relative basis 

e limited, and

stor pressure d

for collected 

fueling is mos

endently of fu

minosity as ill

ease in smoke

adiation heat 

atures corrobo

bustor pressur

Pa)) with con

0.020 to 0.025

sions 

ing, pressure,

Such data are

changes. 

he test F/A va

ithin +12% to

one point at –

an one-to-one

high aromati

ng for 

207 and 

y 

AH) 

articulates.] 

as the blend 

d the data set s

drop. 

smoke data a

st pronounced

ueling yet is lo

lustrated in Fi

e number and 

load on the c

orate this incr

re changes fro

nsistent increa

5. In general t

, F/A and fuel

 necessary fo

alues were com

o –18% of one

–50%. The ge

e corresponde

ic and cyclohy

of JP-8 and F

shown is at 

as shown in 

d at lower F/A

owest at 100%

igure 17 with 

flame lumino

combustor 

rease. 

om 175 to 225

ases in smoke

these trends 

ling composit

or determinati

mpared with t

e-to-one 

eneral trends 

ence (Fig. 19)

ydrocarbon 

FT 

A

% FT 

the 

osity 

5 psia 

e

tion, 

on of 

the 

are 

). 
NASA/TM

The n

in-plane h

probe cap

aperture a

from over

the dilutio

above con

Details of

In term

values (nu

FT) in bet

M—2012-21712

Figure 1

nitrogen gas ti

hardware deta

p outer diamet

aspirated exha

rheating. Both

on probe, the 

ndensation tem

f the facility a

ms of particle

umber/kg-fue

tween (Fig. 2

28 

9.—Alternate f

Figure 20.—E

plane. Parti

emissions/T

cooled, nitro

Probe cap o

diameter 0.

probes wer

out of true c

ip-diluted, wa

ails, the photo

ter = 0.075 in

austed gas ste

h diluted and 

exhaust gas i

mperature of 

and gas emiss

e emissions in

l burn) for JP

1). At an F/A

fuel experimen

Emissions probe

iculate probe is

TC rake probes

ogen gas diluti

outer diameter 

044 in. (1.12 m

re installed. Pho

combustor exh

ater-cooled pa

o and detail in

n. (19 mm) wi

eam is quench

undiluted pro

s further cool

water and org

ions sampling

ndices EIn, the

P-8 and lower 

A of 0.015, the

24 

ntally set F/A ve

es installed at c

s in photo foreg

s in backgroun

on particulate 

= 0.075 in. (19

mm). Both dilute

oto of installed

aust plane pos

articulate prob

nsert are show

ith aperture di

hed by water c

obes were pos

led and dilute

ganics en rout

g probes are g

e general tren

values for FT

e FT emission

ersus CO2-bas

combustor exh

ground with ga

d. Details of th

probe shown in

9 mm) with ape

ed and undilute

 probes shown

sition. 

be is illustrate

wn rotated out

iameter 0.044

cooling, whic

sitioned at the

ed with nitrog

te to the instr

given in Shou

nds with both 

T with the 50

ns index EIn –

ed calculated F

haust exit 

s 

he water 

n inset. 

erture 

ed 

n rotated 

ed in Figure 2

t of true exhau

4 in. (1.12 mm

ch also preven

e combustor e

gen gas. Both 

rumentation s

use et al. (Ref

pressure and 

% blend (50%

–FT is nearly 

F/A. 

20. Because o

ust plane. The

m). The probe

nts probe failu

exhaust plane

types are hel

ampling pane

f. 2). 

 F/A are high

% JP-8 and 50

1⁄4 that of JP-8

of 

e

e

ures 

e. For 

d 

el. 

her EIn

0% 

8 at 
NASA/TM

175 psia (

at 175 psi

(0.517 MP

trends are

engine pre

pressure).

Trend

(Fig. 22) b

is observe

increases 

M—2012-21712

Figur

FT

Dp

EI 

atm

(1.207 MPa); 

ia (1.207 MPa

Pa). Whereas 

e consistent w

essure), yet th

ds with the cle

but not neces

ed, namely the

beyond that o

28 

Figure 21.—

with test 

[Note: Te

FA = 0.01

re 22.—Alterna

T for combustor

p) = 2.833103

= number/kg, a

mospheres and

at F/A = 0.02

a). Note, how

it is difficult 

where FT parti

he difference 

eaner paraffin

sarily in term

e number of p

of JP-8. Howe

—Particulate em

pressure and F

est data set inc

15 and at 225 p

ate fueling parti

r pressure at 75

[dN/d(log Dp)]

and FAR = fue

d T is temperat

20, nearly 1⁄2 a

wever, the vari

to make a dir

iculate emissi

trend diminis

nic fuels (FT) 

ms of the FT b

particulates (N

ever for FT fu

25 

missions numbe

F/A for JP-8, FT

omplete at 75 

psia for FA = 0

cle size distrib

5 psia (0.517 M

[(1+ FAR)/FAR

el:air ratio F/A; P

ture in K (herei

at 225 psia (1

iability of 50%

rect comparis

ions are much

shes with incr

are also refle

lend, where a

N) of size Dp

ueling, the va

er indices varia

T blend, and F

psia and 225 p

0.025.] 

ution with JP-8

MPa) and F/A =

R](T/P) where N

P is instrument

n 1 atm and ~2

.551 MPa); a

% fuel blend a

son with on-w

h lower than J

reased engine

ected in terms

at 75 psia (0.5

p (equivalent d

alues of the [d

ations 

FT fueling. 

psia for 

8, FT blend, an

= 0.025. dEI/d(

N = number/cm

t pressure in 

293 K). 

and at F/A = 0

at lower press

wing engine te

Jet A at low p

e power (high

s of particulat

517 MPa) ano

diameter) per

dN/d(log Dp)] 

d 

(log 

m3, 

0.025, nearly 7

sures of 75 ps

esting, the dat

power (lower 

her engine 

te size distribu

omalous beha

r cubic centim

 derivative 

7/8 

sia 

ta 

ution 

avior 

meter 
NASA/TM

indicate th

diameter p

difficult to

study. 

Partic

tip dilutio

(0.862 MP

Figure 22

Looki

(1.207 MP

Whereas t

minor by 

reasons re

In con

(1.207 MP

= 0.020 ar

blend and

on the figu

that of Fig

The m

(Fig. 26). 

particulate

M—2012-21712

Figur

FT

F/A

wh

ins

an

he total partic

particulates, a

o detect, isola

culate size and

on and probe s

Pa) and F/A =

, and the effe

ing again at th

Pa) shown in 

the cleaner FT

comparison w

emain to be ex

ntrast to the d

Pa) and F/A =

re consistent w

d far more tha

ure. Less pron

gure 24. 

mean particle 

This trend is 

e variations. 

28 

re 23.—Particu

T blend, and FT

A = 0.015. dEI

here N = numbe

strument press

d ~293 K). 

cle counts (int

and the smalle

ate, collect an

d to some ext

secondary dilu

= 0.015. Here

cts of probe d

he anomalous

Figures 21 an

T fuel particu

with those sho

xplored. 

distribution tre

= 0.025 (Fig. 2

with clean fu

n FT fueling 

nounced is th

diameter at 1

not evident in

late size distrib

T fuels for comb

I/d(log Dp) = 2.

er/cm3, EI = nu

ure in atmosph

tegrals) are ne

er (about half

nd dispose of 

tent, distributi

ution are illus

the trend wit

dilution dimin

s trends at com

nd 22, shows 

ulate peak is s

own in Figure

ends at combu

24), the trend

el blending; n

(Fig. 25). The

he variation in

75 psia (1.20

n Figure 24, a

26 

bution changes

bustor pressure

.833103 [dN/d

umber/kg, and 

heres and T is t

early half that

f the size of th

such particula

ion, are highly

strated in Figu

th particulate 

nishes with fu

mbustor press

similar trend

till less than t

e 21 at other p

ustor pressure

ds at combusto

namely JP-8 p

e variation wi

n the particula

07 MPa) decre

adding to the 

s with probe dil

e 125 psia (0.8

d(log Dp)][(1+ F

FAR = fuel:air 

temperature in

t of JP-8. Not

he JP-8 peak)

ates. Further, 

y dependent o

ure 23 for com

size is not as

uel blending. 

sure of 75 psi

ds in particula

that of JP-8 o

pressures. Wh

e of 75 psia (0

or pressure of

produces mor

ith JP-8 fuelin

ate peaking w

eases with fue

complexity o

ution with JP-8

862 MPa) and 

FAR)/FAR](T/P

ratio F/A; P is 

n K (herein 1 at

te the peak sh

) particulates 

the toxicolog

on the probe. 

mbustor press

s definite as il

ia ( 0.517 MP

ate distribution

or the FT blen

hile consisten

0.517 MPa) a

f 225 psia (1.

re particulates

ng is also illu

which is more 

eling blend fr

of predicting c

8, 

P), 

tm 

hift toward sm

making more

gy requires m

Effects of pr

sure of 125 p

llustrated in 

Pa) and 175 ps

n (Fig. 24). 

nd, the trend is

nt, the behavio

and 175 psia 

551 MPa) an

s than the FT 

ustrated as JPconsistent wi

rom JP-8 to F

combustor 

maller 

e

much 

robe 

sia 

sia 

s

oral 

d F/A 

-8(2) 

ith 

T 
NASA/TM

Figure 24.—

and FT f

and F/A 

Dp)][(1 +

EI = num

instrume

tempera

Other

prescribed

A coll

Research 

Technolog

Dayton R

Aircraft (P

provides s

M—2012-21712

—Particle size 

for combustor p

= 0.025. dEI/d

+ FAR)/FAR](T

mber/kg, and FA

ent pressure in 

ature in K (here

r emissions an

d in the Jet A 

laborative [N

Inc. (ARI), E

gy (MST), AS

Research Instit

P&W),] and o

several neede

28 

distribution wit

pressure 175 p

d(log Dp) = 2.83

T/P), where N =

AR = fuel:air ra

atmospheres a

ein 1 atm and ~

Figure 26.—

FT fuelin

and F/A

nd peformanc

fueling speci

ASA, AFRL,

Environmenta

SRC Aerospa

tute (UDRI), U

others small a

ed insights int

th JP-8, FT ble

psia (1.207 MP

33103 [dN/d(lo

= number/cm3, 

atio F/A; P is 

and T is 

~293 K). 

—Mean particl

ng for combust

A values of 0.01

Engine Em

ce tests indica

fications (Ref

, Arnold Engi

l Protective A

ce Corp., Sci

United Techn

and large on-w

to aviations em

27 

nd, 

a) 

og 

Figure

blen

(1.5

2.83

N = 

ratio

and

e diameter with

tor pressure 17

15, 0.020, and 

missions T

ate small to no

f. 4). 

ine Developm

Agency (EPA)

ence Systems

noloigies Rese

wing engine e

missions (Ref

e 25.—Particula

nd, and FT fuel

551 MPa) and F

33103 [dN/d(lo

number/cm3, E

o F/A; P is instr

 T is temperatu

h JP-8, FT blen

75 psia (1.207 

0.025. 

Testing

o changes in e

ment Center (A

), Missouri U

s and Applica

earch Center 

emissions and

fs. 5 and 6). 

ate size distribu

ling at combus

F/A = 0.020. d

og Dp)][(1 + FA

EI = number/kg

rument pressur

ure in K (herein

nd, and 

MPa) 

emssions with

AEDC)/ATA,

University for 

ations Inc. (SS

(UTRC), Pra

d performance

ution for JP-8, 

tor pressure 22

EI/d(log Dp) = 

AR)/FAR](T/P),

g, and FAR = fu

re in atmosphe

n 1 atm and ~2

hin limits as 

 Aerodyne 

Science and 

SA); Universi

att-Whitney 

e test program

FT 

25 psia 

 where 

uel:air 

eres 

293 K). 

ity of 

m
NASA/TM

Small

FT-blende

At low po

NOx 

Lowe

At interm

Very l

There

These

of the two

that for JP

Appro

content of

tested in a

deviations

fueling (F

increases 

particulate

off-wing e

M—2012-21712

l-engine test s

ed fuels: 

ower, 

emissions are

er CO emissio

mediate or high

low CO emis

e is no signific

e tests also re

o FT fuels test

P-8, whereas f

oximately 2%

f synthetic fue

a Pratt & Whi

s were small e

F/A) and engin

with engine p

e diameters fo

engine testing

28 

stand observa

e within instru

ons with FT/b

h power, 

sions make ra

cant differenc

evealed neglig

ted. The SO2

for 100% FT 

% fuel flow be

el. Rahmes et

itney small tu

except for cor

ne power sett

power setting

or JP-8, 50:50

g. 

Figure 27.—S

Small E

ations on a tes

ument measur

blend may be 

atios irrelevan

ce in NOx em

gible unburne

emissions ind

fuel a value o

enefit with 10

t al. (Ref. 7) p

urbine engine 

re smoke (Fig

tings, showing

 (Figs. 28 and

0 blend, and F

Small turbine e

28 

Engine Test

st-stand-moun

rement capab

due to higher

nt to evaluate

missions 

ed hydrocarbo

dicate the sulf

of 0.1% indic

0% synthetic 

provides emis

(inferred as P

g. 27). The pa

g decreases in

d 29). Figure 

FT fueling wi

engine emissio

ting

nted PW 308 

bilities 

r H/C ratio 

e differences b

ons (UHC) at 

fur content of

cates contamin

 fuel can be a

ssions results 

PW 308 and b

articulate distr

n emissions w

30 provides a

ith changes in

ns test results 

engine fueled

between the fu

all power con

f the blend to

nation. 

attributed to th

for an unspec

biofueling). E

ributions chan

with increses i

a comparison

n engine powe

(Ref. 7). 

d by JP-8, FT,

fuels 

nditions for b

 be around 50

he higher hea

cified fuel tha

Emissions 

nge with both

in %FT and 

n of mean 

er for the PW

T, and 

both 

0% of 

at 

at was 

h

W 308 
NASA/TM—2012-21712

Fi

8 

Figure

cha

igure 29.—Cha

(alternative fu

Figure 

with 

308 

e 28.—Variatio

anges (alternati

anges in particu

uels PW 308 en

30.—Variation

fueling and po

engine testing)

29 

n of particulate

ive fuels PW 3

ulate distributio

ngine testing).

s of mean part

ower level (alter

). 

e distribution w

08 engine testi

on with power a

ticulate diamete

rnative fuels PW

with fueling 

ing). 

and fueling 

er 

W
NASA/TM

A con

JP-8 or Je

at various

and refin

either coa

engine po

carbon va

The d

dependen

illustrate t

data are p

M—2012-21712

nsortium of ag

et A1 (JP-8 wi

s power settin

er. Future test

al- or gas-deri

ower setting ar

alues are prov

data presented

cy on fuel com

the dependen

lanned to be r

Figure 31.—O

JP-8 and S8

derived jet f

28 

Lar

gencies are w

ithout military

ngs. Here SPK

ting will inclu

ved jet fuel. P

re provided o

vided on the ri

d herein show

mposition. Th

cies for the d

released in a 

On-wing engine 

8 blend, and 10

fuel, 1 meter do

rge Engine 

orking togeth

y additives), a

K represents d

ude biomass f

Particulate dis

on the left side

ight side of Fi

w a strong dep

he small-engi

ata herein. As

January 2010

emissions test

00% S8, where

ownstream of e

30 

On-Wing T

her to provide

a 50:50 blend

different Fisch

feedstock fue

stributions giv

e of Figure 31

igure 31. 

endence on F

ine test data fi

s for the on-w

0 workshop. 

ting measurem

e S8 represents

exhaust plane (

Test Results

e on-wing eng

d with SPK, a

her-Tropsch fu

eling (HRJ). F

ven by Ander

1. The numbe

F/A and blend

figures are bot

wing engine te

ments for particu

s an FT fueling

(Ref. 8). 

gine emission

and 100% SPK

fuels dependin

For these tests

rson (Ref. 8) 

er of particula

d with an impl

th normalized

est results, the

ulates with JPg with either co

ns testing for 1

K engine fuel

ng on feedsto

s the fuel was

at 30% and 6

ates and black

lied less 

d and too coar

e AAFEX pro

-8, 50:50 

oal- or gas100% 

ling 

ck 

s

65% 

k

rse to 

ogram 
NASA/TM—2012-217128 31 

Measurement precision is much better than potential errors in measurements. For example, if most of 

the particles are >10 nm in size, determination of EI values in the range of (1 to 100)1014/kg fuel 

burned is to about 10% precision. Similarly, the “apparent” black carbon (BC) EI of between 10 and 

1000 mg/(kg fuel burned) is also to about 10% precision. However, estimate of errors can be an order of 

magnitude greater arising from the several factors such as (Ref. 8) 

1. Lack of instrument measurement specificity for black carbon(BC) 

2. Lack of direct measurement approaches for BC mass 

3. Lack of standards: BC characteristics vary widely between and within combustion sources 

4. Severe particulate losses within sampling lines (e.g., 50% to 70% in a 25-m line prior to the 

diagnostic instruments) 

5. Interference from background particulates, which often comprise dust and other refractory 

particles that do not evaporate in the combustor. 

Comparisons of engine on-wing missions data (Ref. 8) and combustor-sector test data herein imply 

(but not conclude at this time) that sector test data replicate, at least qualitatively, on-wing test data, 

providing both detail and insights not gained from on-wing testing, including particulate data. Post 

AAFEX 2010 Workshop data (Ref. 9) also show similar qualitative emissions trends for both gaseous and 

particulate emissions with emissions results herein, yet elude quantitative comparisons for lack of 

measurement scales on many of the AAFEX reported emissions data plots. 

There are qualitative differences in the emissions depending on SPK alternate fueling relative to both 

SPK and JP-8 fueling; however, quantitative values are not given and while these differences appear to be 

minor, but not insignificant, the actual values remain to be demonstrated. While this feedstock 

dependency of the fueling may not be large, it remains to be evaluated, which in turn affects the ASTM 

specifications and the presumption of being feedstock agnostic. 

The EPA (Ref. 10) provided logarithmically-transformed emissions index composites data sets for 

three turbofan engines with selected fueling types similar to those used for AAFEX. These data show 

significant changes with engine and fuel type. Sixty-four semivolatile organic compounds (n-alkanes and 

polycyclic aromatic hydrocarbons (PAH) were measured (Ref. 10). The coupled concerns over engine 

and fuel type may delay FT fueling certification or prompt regulation. 

It should also be noted that current aircraft auxiliary power units (APUs) (2011) have significantly 

higher black carbon emissions than on-wing engines (Ref. 8). 

Conclusions: Part B 

Alternate fueling testing is being carried out to determine preliminary performance, emissions, and 

particulates combustor sector data relative to JP-8+100 as baseline fueling, for SPK-type (e.g., FischerTropsch, FT) fuels blends and projections for testing of biofuel fuel blends leading to preliminary 

development of smart fueling (fuel flexible) and combustor systems for the next generation aeronautic 

and aeronautic-derivative gas turbine engines. Herein alternate fueling test results for a well characterized 

but proprietary combustor are provided for JP-8+100, a FT-derived fuel, and a blend of 50% each by 

volume. 

The test data presented are part of a more extensive data set where combustion parameters were 

varied over a range of values. The data herein are for the case of nominal inlet conditions at 75 psia 

(0.517 MPa) to 225 psia (1.551 MPa) and 800 F (700 K), and JP-8+100 is taken as the baseline. 

The 50:50 blend test performance and emissions results generally are between JP and FT and 

somewhat closer to FT 

 
NASA/TM—2012-217128 32 

Emissions: CO is lower with FT; CO2 is about the same; NO is lower with FT; NO2 is higher with FT 

fueling F/A; NOx is lower to higher with FT with F/A; O2 decreases with F/A (consistent with 

temperature increase), is lower with FT with increased spread from JP-8 with F/A, again consistent with 

rake temperature; HC generally decreases with F/A, yet FT humps at 0.015. No explanation is provided. 

Basic emissions show more change with F/A than with JP-8 or FT; the latter being the more 

significant. These results appear to agree qualitatively to on-wing engine testing. Quantitative agreement 

requires resolution pending data release. The other aspect is to look at how emissions change with 

pressure and EXTRAPOLATE those results to core pressure on the ground, that is, at much higher 

pressures. 

These comparisons and test data presented herein imply—yet at this time cannot conclude—that 

sector test data replicate, at least qualitatively, on-wing test data, providing both detail and insights not 

gained from on-wing tests. Post AAFEX 2010 Workshop analysis of released data and data herein is 

warranted. 

Comparisons of engine on-wing test data (Ref. 8) and combustor-sector test data herein imply (but 

not conclude at this time) replicate, at least qualitatively, on-wing test data, for both gaseous emissions 

and particulate results, providing both detail and insights not gained from on-wing tests. Post AAFEX 

2010 Workshop data (Ref. 9) also show similar qualitative emissions trends with results herein, yet elude 

quantitative comparisons for lack of scales on many of the AAFEX reported data. 

SPK and JP-8 emissions profiles are qualitatively similar, yet there are observable differences in the 

emissions depending on alternate fueling feedstock and engine type, however quantitative AAFEX values 

are not provided and remain to be demonstrated. This feedstock dependency makes it more difficult for 

ASTM to certify as fuel feedstock agnostic and may require conformity to more strict ASTM fuel 

requirements? 

It should also be noted that current aircraft APU’s (2011) have significantly higher black carbon 

emissions than on-wing engines (Ref. 8). 
NASA/TM—2012-217128 33 

Appendix A.—Fuel Specifications 

TABLE A–1.—FUEL SPECIFICATIONS FOR FT FUEL, 

AFRL NO. 5172-6: LAB REPORT 2007LA06946001 

Method Test Result 

 ASTM D 3242–05 Total acid number (mg KOH/g) 0.002 

 ASTM D 1319–05 Aromatics (% vol) 0.0 

ASTM D 3227–04a Mercaptan sulfur (% mass) 0.000 

ASTM D 4294–03 Total sulfur (% mass) 0.00 

ASTM D 86–07a Distillation 

Initial boiling point (C) 148 

10% recovered (C) 162 

20% recovered (C) 163 

50% recovered (C) 169 

90% recovered (C) 185 

End point (C) 198 

 Residue (% vol) 0.9 

 Loss (% vol) 1.1 

ASTM D 93–07 Flash point (C) 44 

ASTM D 4052–96 API gravity @ 60 F 60.5 

ASTM D 5972–05 Freezing point (C) –54 

ASTM D 445–06 Viscosity @ –20 C (mm2

/s) 2.6 

ASTM D 3338–05 Net heat of combustion (MJ/kg) 44.2 

ASTM D 3343–05 Hydrogen content (% mass) 15.6 

ASTM D 1322–97 Smoke point (mm) 40.0 

ASTM D 130–04 Copper strip corrosion (2h @ 100 C) 1a 

ASTM D 3241–06 Thermal stability @ 260 C 

 Change in pressure (mmHg) 0 

 Tube deposit rating, visual 1 

ASTM D 381–04 Existent gum (mg/100 mL) <1 

ASTM D 5452–06 Particulate matter (mg/L) 0.5 

MIL–DTL–83133E Filtration time (min) 3 

ASTM D 1094–00 Water reaction interface rating 1 

ASTM D 5006–03 FSII (% vol) 0.00 

ASTM D 2624–07 Conductivity (pS/m) 233 

ASTM D 5001–06 Lubricity test (BOCLE) wear scar (mm) 0.77 

ASTM D 4809–06 Net heat of combustion (MJ/kg) 44.2 

MIL–DTL–83133E Workmanship Pass 

 
NASA/TM—2012-217128 34 

TABLE A–2.—FUEL SPECIFICATIONS FOR 

AFRL NO. B18-JP8+100: LAB REPORT 2009LA16176001

[ASTM-D1332 smoke point was greater than 40.00 mm.] 

Method Test Result 

 ASTM D 3242–08 Total acid number (mg KOH/g) 0.003 

 ASTM D 1319–08 Aromatics (% vol) 18.5 

ASTM D 3227–04a Mercaptan sulfur (% mass) 0.000 

ASTM D 4294–08a Total sulfur (% mass) 0.05 

ASTM D 86–08 Distillation 

Initial boiling point (C) 160 

10% recovered (C) 178 

20% recovered (C) 163 

50% recovered (C) 203 

90% recovered (C) 240 

End point (C) 261 

 Residue (% vol) 1.3 

 Loss (% vol) 0.8 

ASTM D 93–08 Flash point (C) 46 

ASTM D 4052–96 API gravity @ 60 F 46.0 

ASTM D 5972–05e1 Freezing point (C) –50 

ASTM D 445–06 Viscosity @ –20 C (mm2

/s) 4.2 

ASTM D 3338–08 Net heat of combustion (MJ/kg) 43.3 

ASTM D 3343–05 Hydrogen content (% mass) 13.8 

ASTM D 1322–08 Smoke point (mm) 26.0 

ASTM D 130–04 Copper strip corrosion (2h @ 100 C) 1a 

ASTM D 3241–08a Thermal stability @ 260 C 

 Change in pressure (mmHg) 0 

 Tube deposit rating, visual 1 

ASTM D 381–04 Existent gum (mg/100 mL) 4.4 

ASTM D 5452–08 Particulate matter (mg/L) 0.3 

MIL–DTL–83133F Filtration time (min) 6 

ASTM D 1094–00 Water reaction interface rating ----- 

ASTM D 5006–03 FSII (% vol) 0.10 

ASTM D 2624–07 Conductivity (pS/m) 498 

ASTM D 5001–06 Lubricity test (BOCLE) wear scar (mm) ----- 

ASTM D 4809–06 Net heat of combustion (MJ/kg) ----- 

MIL–DTL–83133F Workmanship Pass 
NASA/TM

The facili

• Pr

• T

• Pr

• Fu

The gener

• S

co

• A

• B

• A

Instrumen

• O

• A

• C

• A

• C

 

Fig

M—2012-21712

App

ty test condit

ressure: 75, 1

Temperature: 5

ressure drops

uel blends: 10

ral operating p

et the approp

ollect data set

Adjust the alte

Blend the alter

Adjust the ratio

ntation contro

Optical access 

Application of

Continuous low

Application of

Characterizatio

ure B–1.—AFR

28 

pendix B.—

Sc

ions were 

125, 175, and 

500, 625, 725

s across comb

00% JP-8, 50

procedures fo

riate pressure

t. 

ernative fuel s

rnative test fu

o mass flow a

ols and charac

into combust

f advanced las

w-pressure al

f advanced sen

on of advance

RL experimenta

—Test Fac

chematic a

225 psia (0.5

5, and 790 F

bustor: –3%, 4

:50, and 100%

ollowed: 

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system pressu

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drop (DP) wi

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in the tests rep

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collect data. 

ported herein.
NASA/TM—2012-21712

Figure B

on de

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Figure B

28 

B–2.—Fueling 

emand. Foregr

em in backgrou

B–3.—Photos o

station adjace

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36 

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ain fuel pump a

ernate fueling tr

ection, providin

and the second

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ng blended fue

dary blending 

acility supply ta

eling 

nk. 
NASA/TM—2012-217128 37 

Appendix C.—Estimates of Measurement Errors 

In this appendix we provide estimates of errors in the data measurements repeatability for the 

combustor, on-wing, and fuel blend ratios and some additional explanations for arriving at those 

estimates. 

Combustor sector experiments 

Thermal measurements: ±0.5% full scale 

Flow measurements: ±1% 

Fuel flow measurements (turbine flow meters ±0.25%) 

Fuel blend ratio less than ±4% 

Static pressure: ±0.1% 

Thermal rake: ±0.5% to 3% 

Emissions rake: ±1% 

Relative carbon balance: ±3% 

Calculated flame temperature: ±3% 

Particulates: ±5% to 10% 

Smoke number: ±3 SN, where SN = [(mg-C)/s ] / [(kg-combustor gas)/s] 

Note 1: Thermocouple geometric placement: ±1.5%. 

Note 2: The relative carbon balance error involves comparison of metered experimental to calculated fuel/air 

ratio (F/A = FAR), determined from the emissions data [CO, CO2, HC and NOx], per SAE Aerospace 

Recommended Practice (ARP) 1533 guidance (Ref. 11). The emissions analyzers are calibrated prior to every 

day-to-day test using certified (2%) gas concentrations. The relative error is considered representative data 

(across industry), when it is between 10% and 15% (10% for engines above idle and 15% at idle). Herein the 

uncertainty in the measured raw emissions data is considered 3%, accurate to the 2% certified gas calibrations 

and accounting for the combined propagated error for the analyzer specifications: 1% full-scale reading. With 

multiple calibration gases the analyzers are accurate with the standard gas, repeatable (precise), such that the 

relative error in the carbon balance is considered accurate to 3%. 

Note 3: The calculated flame temperature is a thermodynamic energy balance between reactants and products, 

utilizing emissions data (efficiency) and experimental operating conditions; it is consistent with temperatures 

determined from thermocouple rakes (based on multiple experiments, to within ±10 °F (±5.6 °C)), which 

reinforces the cited 0.5% error full scale. However, the calculated flame temperature can be no better than 3% 

because it is based on efficiency, as calculated from SAE ARP 1533 [11]. 

Estimates of error for on-wing data 

gaseous emissions ±5 % or better 

Black Carbon (BC) number or mass ±6 % or better 

Particulates measurement variations [not repeatability ( precision) error bands] can be large as there are 

no convenient methods for calibrating instruments. Nanoparticulates are lost on rake placement, probe 

inlets, transport tubing walls and vary by species (Ref. 8), with estimate of error: 

EI Number [200% (dirty engine (APU) and 100% (clean engine)] 

EI mass 50% to 100% 

Error of estimate for fuel blend 

In an analysis to verify fuel blending, samples of the 50/50 blended fuel were collected just upstream 

of the fuel injectors. The FT fuel used to make the JP-8+100/FT blend contained no aromatics (<0.2 

volume %), so analysis of aromatic hydrocarbon content was used to determine the ratio of JP-8+100 in 

the JP-8+100/FT blend. The analysis was performed using ASTM D6379. In this method, normal-phase 

high performance liquid chromatography (HPLC) with refractive index detection was used. The aromatics 
NASA/TM—2012-217128 38 

were eluted from a cyano column (4.6  150 cm) with hexanes as the mobile phase. Standards containing 

mono-aromatics and di-aromatics were used to calibrate the HPLC (Agilent Model 1100). Both standards 

and samples were diluted to the same level (1:50) in hexanes before injection into the HPLC. The 

refractive index peak areas were used to quantify the mono-aromatics and di-aromatics concentrations. 

These were summed to yield the total aromatics content in the fuels in volume percent. The JP-8+100 fuel 

sample contained 17.3 volume % aromatics and the JP-8+100/FT blend sample contained 8.3 volume % 

aromatics. Thus, the ratio of JP-8+100 in the blend was 8.3/17.3 or 0.48, or 48% JP-8+100 and 52% FT to 

within 4%. 
NASA/TM—2012-217128 39 

Appendix D.—Combustor Thermal Data and Post Processing Parameters 

TABLE D–1.—COMBUSTOR OUTER AND INNER LINER TEMPERATURE, THERMAL DIFFERENCE DATA, 

AND NUMBER AND NAME OF THERMOCOUPLES (TCS) USED TO PLOT THERMAL PROFILES.a,b,c

 F/A = 0.010 F/A = 0.015 F/A = 0.020 

TC Unwrappedd JP-8 FT 50:50 JP-8 FT 50:50 JP-8 FT 50:50 

TC No. X  Col C Col G Col F Col O Col K Col M Col Q Col V Col T 

Outer liner 

 0.00 

TOLAL 22 0.94 0.20 817 825 825 852 850 846 882 873 881 

TOLFL 20 0.00 0.22 900 904 907 968 935 946 1030 971 1002 

TOLML 21 0.67 0.26 861 870 869 927 924 925 987 957 985 

TOLMWA 24 0.19 0.32 870 875 878 962 917 944 1027 960 1002 

TOLFM 27 0.00 0.34 899 902 908 983 944 956 1060 985 1024 

TOLCA 25 1.00 0.52 862 872 872 920 910 912 986 952 974 

TOLAM 28 0.94 0.58 814 825 825 852 851 850 888 874 886 

TOLMR 36 0.67 0.62 873 887 884 953 918 941 1013 955 996 

TOLFR 34 0.00 0.74 887 888 891 965 924 944 1016 956 1001 

TOLMWI 23 0.33 0.79 879 879 884 933 905 914 992 937 969 

TOLAR 37 0.84 0.86 831 843 843 877 872 874 917 906 922 

TSWFD 41 0.22 0.97 1218 1288 1280 1438 1469 1444 1544 1565 1581 

TSWFT 30 0.78 1.00 814 820 820 847 836 841 854 842 850 

Inner liner 

TILMWI 38 0.50 1.20 897 908 906 994 969 976 1091 1023 1066 

TILFR 35 0.00 1.23 890 917 919 995 959 967 1075 1006 1050 

TILMWO 26 0.50 1.33 902 908 909 988 962 968 1096 1025 1071 

TILCA 29 1.00 1.50 1056 1065 1058 1229 1217 1219 1411 1326 1348 

TILFL 39 0.00 1.54 913 917 916 1002 970 981 1098 1030 1069 

 2.00 

a

Geometric position accuracy of thermocouple position coordinates is estimated at ±1.5%. b

For nominal inlet pressure 225 psia (1.55 MPa), 800 F (700 K), and 3% combustor pressure drop. c

Note: Col C, G, F, K, M, Q, V, and T are data set tracking identifiers. 

d

X = x/L (which varies from 0 to 1), where x is the TC position measured from the liner inlet and L is the overall liner length. 

 = circumferential TC position measured over the liner outside y/Lθ (0 to 1) and continuing back along the inside liner (1 to 

2), where Lθ is half the unwrapped liner “width.” The normalized unwrapped coordinate ( X,  ) is the TC location (x, y) 

 
NASA/TM—2012-217128 40 

TABLE D–2.—COMBUSTOR OUTER AND INNER LINER TEMPERATURE 

DIFFERENCE WITH RESPECT TO JP-8+100a (TFUEL BLEND – TJP-8) (F) 

[For nominal inlet pressure 225 psia (1.55 MPa), 800 F (700 K), and 3% combustor pressure drop.] 

 F/A = 0.010 F/A = 0.015 F/A = 0.020 

TC Unwrappedc JP-8 FT 50:50 JP-8 FT 50:50 JP-8 FT 50:50 

TC No. X  Col C Col G Col F Col O Col K Col M Col Q Col V Col T 

Outer liner 

Circumferential start point 0.00 

TOLAL 22 0.94 0.20 0 8 8 0 –2 –6 0 –9 ––– 

TOLFL 20 0.00 0.22 0 4 7 0 –33 –22 0 –1 –28 

TOLML 21 0.67 0.26 0 9 8 0 –3 –2 0 –30 –2 

TOLMWA 24 0.19 0.32 0 5 8 0 –45 –18 0 –67 –25 

TOLFM 27 0.00 0.34 0 3 9 0 –39 –2 0 –75 –36 

TOLCA 25 1.00 0.52 0 10 10 0 –10 –8 0 –34 –12 

TOLAM 28 0.94 0.58 0 11 11 0 –1 –2 0 –14 –2 

TOLMR 36 0.67 0.62 0 14 11 0 –35 –12 0 –58 –17 

TOLFR 34 0.00 0.74 0 1 4 0 –41 –21 0 –60 –15 

TOLMWI 23 0.33 0.79 0 0 5 0 –28 –19 0 –55 –23 

TOLAR 37 0.84 0.86 0 12 12 0 –5 –3 0 –11 5 

TSWFD 41 0.22 0.97 0 70 62 0 31 6 0 21 37 

TSWFT 30 0.78 1.00 0 6 6 0 –11 –6 0 –12 –4 

Inner liner 

TILMWI 38 0.50 1.20 0 11 9 0 –25 –18 0 –68 –25 

TILFR 35 0.00 1.23 0 27 29 0 –36 –28 0 –69 –25 

TILMWO 26 0.50 1.33 0 6 7 0 –26 –20 0 –71 –25 

TILCA 29 1.00 1.50 0 9 2 0 –12 –10 0 –85 –63 

TILFL 39 0.00 1.54 0 4 3 0 –32 –21 0 –68 –29 

Circumferential end point 2.00 

Average without TSWFD 8 9 –23 –14 –50 –19 

Average with TSWFD 12 12 –20 –13 –46 –16 

Average 



 



 

2

without with

 10 10 –21 –14 –48 –18 a

Geometric position accuracy of thermocouple position coordinates is estimated at ±1.5%. b

Note Δ°C = ΔK = Δ°F/1.8. c

X = x/L where x is the TC position measured from the liner inlet and Lx is the overall liner length. 

 = circumferential TC position measured over the liner outside/Lθ (0 to 1) and continuing back along inside liner (1 to 2) where Lθ is 

half the unwrapped liner “width.” 

 
NASA/TM—2012-217128 41 

Thermocouple number and name used in plotting thermal and thermal difference profiles. These 

selected TCs provide for nominal axial and circumferential thermal and differential thermal profiles. The 

profiles are not aligned with mutually perpendicular coordinate locations. 

TABLE D–3.—THERMOCOUPLE (TC) NUMBER AND NAME USED IN PLOTTING 

THERMAL AND THERMAL DIFFERENCE PROFILESa 

Liner outer wall 

Axial Circumferential 

Forward (FWD) Midplane (MID) Aft (AFT) 

TC No. TC name TC No. TC name TC No. TC name TC No. TC name 

20 TOLFL 20 TOLFL 21 TOLML 22 TOTAL 

27 TOLFM 27 TOLFM 24 TOLMWA 25 TOLCA 

24 TOLMWA 34 TOLFR 36 TOLMR 28 TOLAM 

21 TOLML 23 TOLMWI 37 TOLAR 

22 TOLAL 

Liner inner wall 

Axial Circumferential 

Forward (FWD) Midplane (MID) Aft (AFT) 

TC No. TC name TC No. TC name TC No. TC name TC No. TC name 

35 TILFR 35 TILFR 38 TILMLWI 29 TILCA 

26 TILMWD 39 TILFL 36 TILMWD 

29 TILCA a

These selected TCs provide for nominal axial and circumferential thermal and differential thermal profiles. The profiles are not 

aligned with mutually perpendicular coordinate locations. 

NASA/TM—2012-217128 43 

References 

1. Hendricks, R.C., Shouse, D.T., Roquemore, W.M., Burns, D.L., Duncan, B.S., Ryder, R.C., Brankovic, 

A., Liu, N.-S, Gallagher, J.R., and Hendricks, J.A., 2004, “Experimental and Computational Study of 

Trapped Vortex Combustor Sector Rig With Tri-Pass Diffuser,” NASA/TM—2004-212507, NASA 

Glenn Research Center, Cleveland, OH. 

2. Shouse, D.T., Stutrud, J.S., and Frayne, C.W., 2001, “High Pressure Combustion Research at the Air 

Force Research Laboratory,” ISABE–2001–1119, Fifteenth International Symposium on Air Breathing 

Engines, Bangalore, India. 

3. Ryder, R.C., Hendricks, R.C., Huber, M.L., and Shouse, D.T., 2010, “Computational Analysis of 

Dynamic SPK(S8)-JP-8 Fueled Combustor-Sector Performance,” submitted to Journal of Engineering 

for Gas Turbines and Power. 

4. Kinder, J.D., and Rahmes, T., 2009, “Evaluation of Bio-Derived Synthetic Paraffinic Kerosenes 

(Bio-SPK),” Sustainable Biofuels Research & Technology Program document, The Boeing Company, 

Seattle, WA. 

http://www.boeing.com/aboutus/govt_ops/reports_white_papers/pas_biofuel_exec_summary.pdf 

5. Bulzan, D., 2009, “Alternative Aviation Fuel Experiment (AAFEX): Overview,” NASA Glenn 

Research Center, Cleveland, OH. 

6. NASA, AFRL, ARI, UTRC, and P&W, 2008, “Alternative Fuel Test on PW308 Engine,” collaborative 

presentation. 

7. Rahmes, T.F., Kinder, J.D., Henry, T.M., Crenfeldt, G., LeDuc, G.F., Zombanakis, G.P., Abe, Y., 

Lambert, D.M., Lewis, C., Juneger. J.A., Andac, M.G., Reilly, K.R., Holmgren, J.R., McCall, M.J., and 

Bozzano, A.G., 2009, “Sustainable Bio-Derived Synthetic Paraffinic Kerosene (Bio-SPK) Jet Fuel 

Flights and Engine Tests Program Results,” AIAA 2009–7002, 9th AIAA Aviation Technology, 

Integration, and Operation Conference (ATIO), AIAA, Reston, VA. 

8. Anderson, B., 2009, “Langley Aircraft Emission Research: Highlights and Overview of the Alternative 

Aviation Fuel Experiment,” AMRD/AAFEX program presentation, NASA Langley Research Center, 

Hampton, VA. 

9. Bulzan, D. et al. (15 authors), 2010, “Gaseous and Particulate Emissions Results of the NASA Alternate 

Aviation Fuel Experiment (AAFEX),” GT2010-23524, Proceedings of ASME Turbo Expo 2010: Power 

for Land, Sea and Air GT2010 June 14-18, 2010 Glasgow, Scotland. 

10. Kinsey, J.S., Hays, M.D., Don, Y., Williams, D.C., and Logan, R., 2011, “Chemical Characterization of 

the Fine Particle Emissions from Commercial Aircraft Engines during the Aircraft Particle Emissions 

eXperiment (APEX) 1 to 3,” Environmental Science Technology, 23 March 2011, 

http://pubs.acs.org/doi/abs/10.1021/es103880d. 

11. SAE International, 2004, “Procedure for the Analysis and Evaluation of Gaseous Emissions from 

Aircraft Engines,” Aerospace Recommended Practice 1533A. 
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Alternate-Fueled Combustor-Sector Performance 

Part A: Combustor Performance 

Part B: Combustor Emissions 

5a. CONTRACT NUMBER

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5c. PROGRAM ELEMENT NUMBER

6. AUTHOR(S)

Shouse, D., T.; Neuroth, C.; Hendricks, R., C.; Lynch, A.; Frayne, C., W.; Stutrud, J., S.; 

Corporan, E.; Hankins, Capt., T. 

5d. PROJECT NUMBER

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WBS 561581.02.08.03.16.03 

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John H. Glenn Research Center at Lewis Field 

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Available electronically at http://www.sti.nasa.gov 

This publication is available from the NASA Center for AeroSpace Information, 443-757-5802

13. SUPPLEMENTARY NOTES

14. ABSTRACT

Alternate aviation fuels for military or commercial use are required to satisfy MIL-DTL-83133F(2008) or ASTM D 7566 (2010) standards, 

respectively, and are classified as “drop-in” fuel replacements. To satisfy legacy issues, blends to 50% alternate fuel with petroleum fuels 

are certified individually on the basis of processing and assumed to be feedstock agnostic. Adherence to alternate fuels and fuel blends 

requires “smart fueling systems” or advanced fuel-flexible systems, including combustors and engines, without significant sacrifice in 

performance or emissions requirements. This paper provides preliminary performance (Part A) and emissions and particulates (Part B) 

combustor sector data. The data are for nominal inlet conditions at 225 psia and 800 °F (1.551 MPa and 700 K), for synthetic-paraffinickerosene- (SPK-) type (Fisher-Tropsch (FT)) fuel and blends with JP-8+100 relative to JP-8+100 as baseline fueling. Assessments are made 

of the change in combustor efficiency, wall temperatures, emissions, and luminosity with SPK of 0%, 50%, and 100% fueling composition 

at 3% combustor pressure drop. The performance results (Part A) indicate no quantifiable differences in combustor efficiency, a general 

trend to lower liner and higher core flow temperatures with increased FT fuel blends. In general, emissions data (Part B) show little 

differences, but with percent increase in FT-SPK-type fueling, particulate emissions and wall temperatures are less than with baseline JP-8. 

High-speed photography illustrates both luminosity and combustor dynamic flame characteristics.

15. SUBJECT TERMS

Combustors; Engines; Fuels; Environment; Testing 

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