NATIONAL BUREAU OF STANDARDS REPORT

3929

REFRIGERATION AND FIELD EQUIPMENT

PROGRESS REPORT

August 1, 1954 to December 31, 1954

To

HEADQUARTERS; QUARTERMASTER RESEARCH & DEVELOPMENT COMMAND

NATICK, MASS.

U. S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS
U. S. DEPARTMENT OF COMMERCE

Sinclair Weeks, Secretary NATIONAL BUREAU OF STANDARDS

A. V. Astin, Director

cover of this report.

Electricity. Resistance and Reactance Measurements. Electrical Instruments. Magnetic

Measurements. Electrochemistry.

Optics and Metrology. Photometry and Colorimetry. Optical Instruments. Photographic

Technology. Length. Engineering Metrology.

Heat and Power. Temperature Measurements. Thermodynamics. Cryogenic Physics. Engines

and Lubrication. Engine Fuels. Cryogenic Engineering.

Atomic and Radiation Physics. Spectroscopy. Radiometry. Mass Spectrometry. Solid State Physics. Electron Physics. Atomic Physics. Neutron Measurements. Infrared Spectros- copy. Nuclear Physics. Radioactivity. X-Ray. Betatron. Nucleonic Instrumentation. Radiological Equipment. Atomic Energy Commission Radiation Instruments Branch.

Chemistry. Organic Coatings. Surface Chemistry. Organic Chemistry. Analytical Chemistry.

Inorganic Chemistry. Electrodeposition. Gas Chemistry. Physical Chemistry. Thermochemistry.

Spectrochemistry. Pure Substances.

Mechanics. Sound. Mechanical Instruments. Fluid Mechanics. Engineering Mechanics. Mass

and Scale. Capacity, Density, and Fluid Meters. Combustion Control.

Organic and Fibrous Materials. Rubber. Textiles. Paper. Leather. Testing and Specifications. Polymer Structure. Organic Plastics. Dental Research.

Metallurgy. Thermal Metallurgy. Chemical Metallurgy. Mechanical Metallurgy. Corrosion.

Mineral Products. Porcelain and Pottery. Glass. Refractories. Enameled Metals. Concreting

Materials. Constitution and Microstructure.

Building Technology. Structural Engineering. Fire Protection. Heating and Air Conditioning. Floor, Roof, and Wall Coverings. Codes and Specifications.

Applied Mathematics. Numerical Analysis. Computation. Statistical Engineering.

Electronics. Engineering Electronics. Electron Tubes. Electronic Computers. Electronic

Instrumentation. Process Technology.

Radio Propagation. Upper Atmosphere Research. Ionospheric Research. Regular Propagation

Services. Frequency Utilization Research. Tropospheric Propagation Research. High Frequency

Standards. Microwave Standards.

®Office of Basic Instrumentation ^Office of Weights and Measures.
NATIONAL BUREAU OF STANDARDS REPORT

ms PROJECT NBS REPORT

1003-20-4^32 February 3, 1955 3929

REFRIGERATION AND

FIELD EQUIPMENT

Progress Report

August 1, 1954 To December 31, 1954

by

Co Wo Phillips

P. Ro Achenbach

Heating and Air Conditioning Section

Building Technology Division

for

HEADQUARTERS, QUARTERMASTER RESEARCH & DEVELOPMENT COMMAND

NATICK , MASS.

<NBS>

U. S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS

The publication, reprlntln

unless permission Is obtaii

25, D, C. Such perm Issio

cal ly prepared If that ag

Approved for public release by the *< is prohibited Director of the National Institute of ds ' Washin s,on Standards and Technology (NIST)

as been speufi ' „ , _ „ or its own use, on October 9, 201 5.

PROGRESS REPORT

REFRIGERATING AND FIELD EQUIPMENT

HEADQUARTERS:

QUARTERMASTER RESEARCH AND DEVELOPMENT COMMAND

August 1, 1954 Through December 31, 1954

1, INTRODUCTION

This report summarizes activities of the Heating and Air

Conditioning Section, Building Technology Division, National

Bureau of Standards in behalf of the Mechanical Engineering

Division Headquarters, Quartermaster General Research and

Development Command, tJ„ S. Army, The report covers a fivemonth period, and includes a summary of the approximate expenditures for each project attached at the end, giving three

figures; direct labor, supervision and services, and supplies

and other expenses.

The specialized knowledge of nearly all members of the

staff of the Heating and Air Conditioning Section has been

utilized at times to further the work for QMR&D. Of these,

ten have spent from 2

5

$ to 90$ of their time during this reporting period to accomplish the work reported herein. The

services and facilities of other sections at NBS have been

drawn on as required. The principal activities on this program are itemized below, together with a discussion of the

progress during the present reporting period or their status

at the end of the reporting period. Items 1, 2, 3? 4 and 14

were completed during this reporting period.

Item 1, PREVIOUS PROGRESS REPORT

N.B.S. Report No. 3635, covering activities in the period

from December 1, 1953 through July 31, 1954 was submitted on

August 23, 1954.

Item 2. 1/3-TON THERMO KING REFRIGERATING UNIT

N.B.S. Report No. 3790, Effect of Engine and Fan Speeds

on the Capacity of The l/3-Ton Thermo King Refrigerating Unit,

Model Q15G, was completed and submitted on November 12, 1954o

It covered a study of the effect of various engine and fan

speeds on the net refrigerating capacity of the l/3-ton gasoline-driven warehouse unit, to permit determination of the

possibility of reducing the number of models of such equipment
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by using each model over a wider range of capacities. As

designed the fan and engine speed proportions were fixed

by pulley sizes. Optimum speeds for engine and fans, when

varied independently, were determined. The fact that the

design engine and fan speeds did not achieve the maximum

net refrigerating capacity indicated the need for study of

other items of similar nature and for further study of the

application of fans and blowers for low-temperature refrigerating service generally.

A request for more detailed information concerning the

various tests has been received and this material is currently

being assembled.

Item 3. DEFROSTING CHARACTERISTICS OF THE 1-TON

REFRIGERATING UNIT

N.B.S. Report No. 3735? Defrosting Characteristics of

the Thermo King 1-Ton Warehouse Refrigerating Unit, Model MQ51,

was completed and submitted on October 12, 1954° Defrosting

performance of both the gasoline-driven and electric motordriven models of this important item was outlined. Quantities

of frost required to block the refrigerating coil, and the

effect on internal warehouse temperatures during the periods

required for defrosting were reported, for conditions of empty

warehouse and with the warehouse loaded with simulated frozen

food. The studies were also divided between operation under

manual selection of defrosting time and automatic defrost

timing as provided originally by the equipment manufacturer.

This study of defrosting characteristics is directly related to the problem of heating (full or partial reverse cycle)

by means of refrigerating equipment. For portable equipment s the warehouse might be exposed to temperatures both above and

below the desired product temperature and in such cases, the

ability of a single piece of apparatus to both heat and cool is

needed. Possible applications of refrigerating equipment as

space heating apparatus, using it as a heat pump, or salvaging

waste heat from the exhaust gases of the gasoline engine is

currently under study in a separate portion of this project,

and is reported under Item 5°

Item 4. REVISION OF FEDERAL SPECIFICATION AA-R-211c

The Federal Specification covering Refrigerators, Electric

Self-Contained, has been under revision during this and the pre

vious reporting period. The draft for AA-R-211d has been completed and will be submitted before January 15, 1955. Although

the previous specification, AA-R-211c, covered domestic, shipboard, and commercial refrigerators up to 100 cu.ft., the pro-

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posed draft for AA-R-211d covers only domestic refrigerators

up to 15 cu.ft. It is hoped that the Heating and Air Conditioning Section can revise the specification for commercial

refrigerators, since much of the information gathered on domestic refrigerators, in reference to use of plastics, metals,

methods for defrosting, methods for testing, etc OJ can be

applied to this portion of the specification* Shipboard refrigerators will probably be covered in a separate specification which can either be included in or patterned after an

applicable Navy specification.

The proposed draft recognizes that domestic refrigerators

are divided into types determined first, by whether a compartment suitable for storage of frozen foods is provided, and

second, whether the defrosting process is started manually or

by means of an automatic device.

The use of plastics was covered in some detail in the light

of experience gained during field trips to manufacturing plants

during the first phase of this work. Test procedures were generally made to agree with NEMA recommendations as outlined in

proposed ASA Standards within the scope covered by these standards, Several conferences were held with Mr, Joe V, Davidson,

QMR&D representative, during the period in which the proposed

draft was being prepared.

Item 5. DEVELOPMENT OF EXHAUST GAS TO REFRIGERANT

HEAT EXCHANGERS

Since all low-temperature refrigerating apparatus must be

defrosted, the importance of improving the defrosting characteristics of the various items of portable gasoline-driven refrigerating units was recognized early in the research and development program of QMR&D, During this reporting period, studies were continued of two methods of utilizing some of the

waste heat in the exhaust gases of the gasoline engine. For

each of these methods, the normal cooling coil in the conditioned or refrigerated space is used as a heating surface during defrosting or heating. In the method proposed by QMR&D, a

heat exchanger is provided in the exhaust line from the engine

which is refrigerated by vaporizing refrigerant, with the flow

controlled by a thermostatic expansion valve, and the normal

evaporator is employed as a condenser. In a second method proposed by NBS a heat exchanger is also installed in the exhaust

line from the engine. The discharge gas from the refrigerating

compressor is forced through this exchanger and superheated to

the highest practical temperature, not over 350 to 400 F, then

permitted to flow through the normal evaporator. In this system

little, if any, of the refrigerant is condensed during heating

or defrosting. There appears to be advantages for each system,
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and the first phase of the investigation in ambient temperatures

of 35 F and above has demonstrated that each is feasible* The

second phase of the investigation which is now in progress is

expected to provide further data on the two when operated in

ambient temperatures approaching -30 F. Attempts to operate

this equipment at lower ambient temperatures have brought to

light many difficulties, primarily connected with malfunctioning

of the gasoline engine. Failure of oil lines, distributor points,

fouling of spark plugs, failure of water jacket gaskets, contamination of lubrication oil, sticking of governor linkage, freezeout of water in gas lines, blocking of the engine breather with

ice, blocking of the exhaust line with condensate and other waste

material, are representative of the sort of mechanical difficulties present in low-temperature investigations.

One item noted particularly with the commercial heat exchanger used for the first method with the vaporizing refrigerant circuit was the rapidity with which foreign material in the

exhaust gas plugged the exhaust vapor passages through the heat

exchanger. Other designs for the heat exchanger to be used will

probably improve this characteristic.

Using the vaporizing refrigerant system incorporated in the

first method and the commercial heat exchanger, a heating capacity of approximately 7000 to 3000 Btu/hr has been observed when

the warehouse temperature was at 15 F and the apibient temperature

of the engine was minus 20 F. Values have been observed at lower

ambient temperatures and other warehouse temperatures, but the

runs have been interrupted by mechanical failures before steady

state conditions have been attained. This series will be concluded in the near future, and this same system will be observed using

another type of heat exchanger, before both types of heat exchangers are tested in low ambient temperatures with the superheated

refrigerant system incorporated in the second method.

It is anticipated that the Wisconsin VE4 air-cooled gasoline

engine will be used for the tests of the superheated refrigerant

system, since this type of engine may be used for the one-ton

warehouse unit in future production.

Item 6. MODIFICATION OF CONTROLS FOR THE ONE-TON

REFRIGERATING UNIT

Work has been continued during this reporting period on the

general modification of the present complex electrical control

system for the 1-ton gasoline-driven warehouse refrigerating

unit. Manufacturers of control devices, such as thermo-mechanical
> .
5

servo-mechanisms, engine governors, temperature limit devices,

etc., have been consulted in regard to available controls, or

their ability to modify present commercial items. It appears

generally that the ability of these manufacturers to construct

modified controls will be the solution of this problem.

In general the proposed system would operate in the following manner: A temperature-sensing thermo-mechanical device would

determine the need for either cooling or heating, or neither, and

regulate control valves for refrigerant flow, and regulate the

speed of the gasoline engine from a minimum safe idling speed

when neither heating or cooling is needed to a maximum safe engine speed when maximum cooling or heating is required. The gasoline engine would remain in operation except when being serviced

and consequently would require smaller capacity cranking facility

or manual cranking means for systems below 15 engine horsepower.

No electrical controls, with the possible exception of engine

over-temperature would be employed. Thermo-mechanical controls

of a type familiar to both automotive and refrigeration personnel

would generally be used for temperature regulation in the controlled space. The engine speed would be regulated by a governor

which is adjusted by need for varying capacity. In this way auto

matic governor protection against run-away speeds is assured, and

variation of throttle position in response to varying loads, does

not interfere with average engine speed which is determined by

adjustment of the governor in direct relation to deviation of the

temperature from desired control point in the controlled space.

This work will be continued.

Item 7. 1/3-TON CARRIER REFRIGERATING UNIT

The first draft of a report of performance investigations

on the l/3-ton gasoline-driven warehouse refrigerating unit,

Carrier Model D731 was completed during this reporting period

and is currently being reviewed.

Item 3. 1/2-TON THERMO KING REFRIGERATING UNIT

The first draft of a report of a study of capacity and other

performance characteristics of the l/2-ton gasoline-driven Thermo

king warehouse refrigerating unit, Model K-10 was completed prior

to this reporting period and is currently under review.

Item 9. COMPRESSOR STANDARDIZATION

Engineering assistance and recommendations on test methods

and procedures were made to representatives of Consultants, Inc.,

under contract to QMR&D, during two conferences requested by

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the contractor. A review of the apparatus required to perform

the various performance, capacity, and general qualification

tests referred to in the proposed compressor standardization

program has been made to determine whether facilities of this

section will meet the requirements. It is believed that a majority of the apparatus and trained personnel are currently available within the facilities of this section.

Item 10. INSULATED FOOD CONTAINERS

Three insulated food containers have been readied for test

at ambient temperatures of minus 40 F and perhaps minus 70 F.

Low temperature facilities at NBS are currently being readied

for these tests.

Item 11. INSULATED REFRIGERATED TRAILER

Preparations have been made as requested for prompt testing

of the thermal loss or gain characteristics of an insulated,

refrigerated semi-trailer scheduled for delivery to this Bureau

during January.

Item 12. REPORTS IN PROGRESS

At the end of this reporting period, final reports of tests

or studies of several items are in progress. These include the

Tent Heaters, Sectional Air Conditioner, Electric Conversion of

the Thermo King Model MQ 51*

Item 13. AIR DISTRIBUTION IN REFRIGERATED TRAILERS

No work was done on this project during this reporting

period. The trailer has been equipped with thermocouples and

the type of air flow measuring devices to be used have been selected. A simulated food load consisting of 1.1 cu.ft. cases

of combat food rations has been placed in the trailer and the

trailer has been installed in a test area suitable for the tests

proposed. Work can be resumed at any time.

A study of the behavior of moisture in refrigerated trailers, including its entrance into the insulated walls, entrapment,

and passage into the refrigerated space, effect of steam cleaning,

racking, wind velocities, etc., is contemplated by this section

for another agency. This work can be of direct interest to QMR&D,and

QMR&D participation in the project is invited.

Item 14. LANTERNS

Work was commenced during' this reporting period on an intensive testing program for a better evaluation of the operating
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characteristics of the Cdleman Inverted Lantern, Gasoline,

T-53-5* Under investigation were the pressures generated

in the fuel tank in high ambient temperatures, the ability

of the lanterns to operate satisfactorily on leaded gasoline,

and the likelihood the lanterns exploding if the pressure

regulator failed to function. NBS Report No. 3$53, covering

the results of these studies on operating characteristics

was prepared and submitted under date of December 30, 1954«

Item 15. VAPOR TRANSMISSION STUDIES

Two tests were completed on the first insulated warehouse

panel in the water vapor transmission apparatus without gaskets

on the warm side of the panel. The temperature and relativehumidity averaged 110. 2°F and 70$ on the warm side and 36.6°F

and 20$ on the cold side, respectively, during the first test,

whereas these quantities averaged 109. 9°F and 62.4$ on the warm

side and -0.1°F and 70. £$ on the cold side, respectively, during the second test.

Approximately a week’s operation was required in each case

to cause condensation or frost to occur on the interior side of

the metal skin on the cold side of the panel. In the first test

condensation was observed on the upper right plexiglas inspection window only. The wooden frame members were wetted on the

upper half of the panel and free water was observed in the hook

openings of the top and middle panel fasteners. The top hooks

were badly rusted. In the second test frost was observed on

all five plexiglas windows. Frost formed around some of the

hooks in the upper and middle panel fasteners to a degree that

made operation of the fasteners difficult. Frost was found between the mating wooden members at the panel joint on the upper

half of the panel. There was frost on the insulation fibers

at the upper two inspection windows on the cold side of the

panel but the warm side of the panel was dry.

Item 16. INVENTORY OF QMR&D ITEMS ON HAND AT NBS

A list of the items on hand at the end of the previous reporting period was submitted with the previous progress report.

With the exception of the l/3-ton Thermo King Model Q15G, and

four Inverted Coleman Gasoline Lanterns this equipment is still

on hand. Three insulated food containers have been received

for test during this reporting period, and two sets of artic

clothing have been received for use in the low ambient temperature tests of the MQ51 heat exchangers. A Wisconsin air-cooled

gasoline engine, Model VE4, was received for use in the modified

1-ton warehouse refrigerating unit. A Westinghouse home freezer

and a Frigidaire refrigerator were loaned to the section by

their respective manufacturers for tests in connection with

the revision of Federal Specification AA-R-211c. These last

two items are, of course, still the property of the manufacturers and will be returned to them in accord with instructions*

2. EXPENDITURES

The total funds expended on work in behalf of QMR&D for

the period August 1, 1954 through December 31 > 1954 are summarized in the attached table. Three figures are given for each

item for the entire period, the first is the amount expended on

labor only, the second is the amount expended for supervision

and services, and the third is the amount spent on all other

items, such as materials, supplies, travel, photographs, printing, etc. The item numbers refer to item numbers in this progress report. The total expenditures reported at the bottom of

the table for the period are the figures taken from the records

of the Accounting Section; all other figures are the best approximations which can be made on the basis of records available.

TABLE 1

APPROXIMATE EXPENDITURES ON VARIOUS PROJECTS FOR

QMR&D — AUGUST 1 — DECEMBER 31, 1954

ITEM Labor

Supervision

and

Services

Materials

And All

Other Expenses TOTAL

1,10,11,12,13,16.

Progress Report

j

Food Containers,

Trailers, Inventory, Other Reports

$ 670 $ 260 #130 $1060

2. l/3-Ton ThermoKing 5«5 225 100 910

3* Defrosting 1-Ton

Unit 230 90 70 390

4« Refrigerator Spec. 3650 1395 220 5265

5* Exhaust Gas Refrigerant Heat

Exchangers

5130 I960 760 7850

6. Modification of

Controls On 1-Ton

Unit

3510 1340 360 5210

7. l/3-Ton Carrier

Unit 520 200 720

3. l/2-Ton ThermoKing Unit 60 20 30

9* Compressor Standardization 135 50 - 135

14. Gasoline Lanterns 1390 720 290 2900

15* Vapor Transmission 710 270 3 50 1330

TOTALS $17090 $6530 $2230 $25900
. • ' •: • >
THE NATIONAL BUREAU OF STANDARDS

Functions and Activities

The functions of the National Bureau of Standards are set forth in the Act of Congress, March

3, 1901, as amended by Congress in Public Law 619, 1950. These include the development and

maintenance of the national standards of measurement and the provision of means and methods

for making measurements consistent with these standards; the determination of physical constants and properties of materials; the development of methods and instruments for testing materials,

devices, and structures; advisory services to Government Agencies on scientific and technical

problems; invention and development of devices to serve special needs of the Government; and the

development of standard practices, codes, and specifications. The work includes basic and applied

research, development, engineering, instrumentation, testing, evaluation, calibration services, and

various consultation and information services. A major portion of the Bureau’s work is performed

for other Government Agencies, particularly the Department of Defense and the Atomic Energy

Commission. The scope of activities is suggested by the listing of divisions and sections on the

inside of the front cover.

Reports and Publications

The results of the Bureau’s work take the form of either actual equipment and devices or published papers and reports. Reports are issued to the sponsoring agency of a particular project

or program. Published papers appear either in the Bureau’s own series of publications or in the

journals of professional and scientific societies. The Bureau itself publishes three monthly periodicals, available from the Government Printing Office: The Journal of Research, which presents

complete papers reporting technical investigations; the Technical News Bulletin, which presents

summary and preliminary reports on work in progress; and Basic Radio Propagation Predictions,

which provides data for determining the best frequencies to use for radio communications throughout

the world. There are also five series of nonperiodical publications: The Applied Mathematics

Series, Circulars, Handbooks, Building Materials and Structures Reports, and Miscellaneous

Publications.

Information on the Bureau’s publications can be found in NBS Circular 460, Publications of

the National Bureau of Standards ($1.00). Information on calibration services and fees can be

found in NBS Circular 483, Testing by the National Bureau of Standards (25 cents). Both are available from the Government Printing Office. Inquiries regarding the Bureau’s reports and

publications should be addressed to the Office of Scientific Publications, National Bureau of Standards, Washington 25, D. C.
NBS