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NATIONAL BUREAU OF STANDARDS REPORT

5427

PROGRESS REPORT FOR QUARTER ENDING JUNE 30, 1957

on

REFRIGERATION AND FIELD EQUIPMENT

by

C. W. Phillips

P. R„ Achenbach

Report to

Quartermaster Research and Engineering Command

Department of the Army

Natick, Massachusetts

<NBS>

U. S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS
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 back 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 N BS Circular 460, Publications of

the National Bureau of Standards (SI .25) and its Supplement ($0.75), available from the Superintendent of Documents, Government Printing Office, Washington 25, D. C.

Inquiries regarding the Bureau’s reports should he addressed to the Office of Technical Information, National Bureau of Standards, Washington 25, D. C.
NATIONAL BUREAU OF STANDARDS REPORT

NBS PROJECT MBS REPORT

1003-20-4832 August 8, 1957 5427

PROGRESS REPORT FOR QUARTER ENDING JUNE 30, 1957

on

REFRIGERATION AND FIELD EQUIPMENT

by

C. W. Phillips and P. R. Achenbach

Air Conditioning, Heating, and Refrigeration Section

Building Technology Division

to

Quartermaster Research and Engineering Command

Department of the Army

Natick, Massachusetts

IMPORTANT NOTICE

NATIONAL BUREAU 01 S F

intended for use within the I to additional evaluation and r listing of this Report, either i the Office of the Director, Na

however, by the Government

to reproduce additional copie

Approved for public release by the

Director of the National Institute of

Standards and Technology (NIST)

on October 9, 201 5.

Mogress accounting documents

anally published it is subjected

reproduction, or open-literature

;ion is obtained in writing from Such permission is not needed,

prepared if that agency wishes

<NBS>

U. S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS
'
PROGRESS REPORT FOR QUARTER ENDING JUNE 30, 1957

on

REFRIGERATION AND FIELD EQUIPMENT

by

C. W. Phillips and P. R. Achenbach

Introduction

The projects reported are limited to those carried on

under Order No. 57-21 and include the gas engine exhaust-torefrigerant heat exchanger, two Kentucky trailers, study of

refrigerated structures, metering heat sink, and the refrigerator specification. The work done on the Kentucky trailers,

refrigerated structure study and metering heat sink is discussed

under the project title "Metering Heat Sink for Refrigerated

Structures." A project cost breakdown is included at the end of

the report.

Exhaust Gas -to-Refrlgerant Heat Exchanger

Modification of the test setup for this important study

to permit determination of the heating ability of a standard

one-ton refrigerating unit equipped with the NBS prototype

exhaust gas-to-refrigerant heat exchanger was continued during

this quarter. The study has been renewed after being dormant

for about two years. The modification, which is about 90%

complete, is intended to provide test conditions of minus 40F

on uhe condenser side and 35^ on the evaporator side of the

unit with the prototype heat exchanger. Temperatures on the

condenser side below minus 20F were not possible previously.

The original liquid-cooled Crosley engine has been replaced by

a model VE4 Wisconsin air-cooled engine, equipped with an

external electric motor for cranking at the low temperature.

Failure of the engine to crank and start readily at low

temperatures was a primary source of test difficulty in the

previous tests. The prototype heat exchanger has been equipped

with improved headers to facilitate rodding of the exhaust gas

tubes which is necessary at regular intervals.

Metering Heat Sink for Refrigerated Structures

Reference is made to NBS Report No. 9283 , Progress

Report for Quarter Ending April 6, 1957^ submitted to

Quartermaster Research and Engineering Command under date

2

of May 14, which includes part of the work actually done

during the quarter currently being reported (ending June 30., 1957)

in connection with the metering heat sink. On pages 3 and 4

of Report No. 5283:, "April 1" should be corrected to read

"May 1.”

As discussed in Report No. 5283;, a Kentucky Mod. No.

M-349 21-foot insulated semitrailer (Ser. No. 18060, NBS

No. 127-56) was used for the tests with the metering heat sink.

On March 28 the insulated spaces in the trailer walls, ceiling,

and floor had been inspected, following which the inspection

openings were patched with metal plates. About 45 holes,

some three-inch and some four-inch, were drilled in the trailer

exterior at various locations: ten in the roof; ten on each

side wall, five near the top and five near the lower edge;

four on each end, two near the top and two near the lower edge;

seven in the bottom.

Without allowing any of the ice in the walls to melt, the

test was continued at conditions of OP trailer temperature and

110F ambient temperature at 60 percent relative humidity. The

rate of frost and ice gain (by weight) was about 1.3 pounds per

hour, as compared to about 1.2 pounds per hour at the start of

the first test without any holes cut in the exterior, and as compared with about 0.7 pound per hour just before the March 28

inspection when 85O pounds of frost and ice had been accumulated

in the insulating space.

The test was continued until about May 1, when the inspection patches were removed and the ice accumulation again observed.

About 500 pounds more ice had accumulated in the insulated space,

and the heat transfer rate with an ambient humidity of 60%

had started to increase at a sharper rate, the rate being

about 90Btu per hour (°F) by May 1. Before the walls were

opened for inspection, the humidity in the test room was lowered

to 15$ and a check of the heat transfer rate with the

additional 500 pounds of ice, and at the lower humidity, was made.

These data have not yet been analyzed, but appear to show the

same decrease as for the previous tests when nothing other than

the humidity was changed.

The significant comparison between the two phases is the

little change in the rate of weight gain with no holes cut in the

exterior and with many holes cut in the exterior. Careful

examination of the vehicle body shows a few openings in the

bottom exterior at the corners. Drops of water had been observed

prior to this series of tests emerging around rivet heads and

coming through seams, etc., when the exterior skin had been
.
3

cooled suddenly, permitting condensation to form on the inside

of the exterior skin.

The examination of the walls on May 1 showed little

increase of ice or frost in or at the floor or at the lower edge

of the walls. There was some increase in the amount of frost at

the top edge of the walls and a great increase in the frost along

the center of the top, being heaviest at or near the holes cut

into the top exterior surface „ Photos of these areas were made

and will be included in the project report.

Following the examination of the insulated spaces on May 1,

the trailer interior was heated to a temperature of 135^ and

the ambient temperature was lowered to 35P for defrosting.

Approximately two days were required for the trailer interior

to reach 135^ under these conditions with an internal electric

heating supply of about 7200 Btu/hr. During this two-day

period about 1000 lbs. of ice melted and the water drained from

many openings (under rivet heads, at seams, etc.) in the trailer

exterior.

For the next fifteen days conditions were maintained at

135P trailer interior temperature and 35F ambient temperature.

The trailer continued to lose weight and was still dripping at

the conclusion of this period. The weight reduction during the

fifteen days was about 225 lbs , an average of 15 lbs per day,

and the apparent heat transfer rate dropped from 117 Btu/hr

(°F) to 78 Btu/hr. (°F) during the same period. In the last

twenty-four hours of the test six pounds of water were driven

from the insulated spaces of the trailer. If it is assumed

that this water was evaporated, the observed heat transfer rate

of 78 Btu/hr (°F), can be corrected to eliminate the effect of

evaporating six pounds of water per 24 hours. The resulting

heat transfer rate would be 75 Btu/hr (°F), as compared

weth an observed initial heat transfer rate of about 68 Btu/hr

(°F) before the trailer was subjected to the ice accumulation

test

About 200 lbs of water remained in the insulation when

this test was arbitrarily concluded. Examination showed that

the insulation at the center of the roof was still very wet,

becoming less wet near the edges of the roof, indicating that

the water vapor was moving to the inside of the cold exterior

skin where it condensed and drained out of openings at the

lower edge of the trailer walls. The data from this test are

being studied for more detailed reporting.

- 4 -

Following the defrosting period, the trailer was again

refrigerated using the prototype metering heat sink to

determine the effect on the heat transfer rate and the rate of

water pickup caused by sealing certain obvious openings in the

bottom exterior skin of the trailer. These tests were concluded

at the end of this quarter and the data will be analyzed and

reported on in the next progress report.

The metering heat sink was modified during this quarter

by substituting more suitable flooded chillers for the

methylene chloride brine in place of the previous combination

of chillers. Photos have been taken and will be included in

the final report on this task.

A search is in progress for a more suitable brine than

methylene chloride, and for better materials for flexible brine

lines

During the next quarter air infiltration tests will be

made both with the Kentucky trailer used for the ice-accumulation

tests and also with a second Kentucky trailer (Mod. No. M349

Ser. No. l8029.> NBS Nc>. 124-56) similar to the first but which

has not had holes cut in the exterior skin for examination

of the insulated spaces.

One conference between representatives of the Air

Conditioning, Heating, and Refrigeration Section, NBS, and of

QMR & EC was held at Natick on April 9 and several conferences were

held at NBS during the quarter, dealing largely with one or

more of these projects.

Refrigerator Specification

Preparation of facilities for testing domestic refrigerators

was completed and tests of the first of four domestic refrigerators were commenced during this quarter. In compliance with

a QMR & E directive dated March 13 (QMRDO-M) four current

model domestic electric refrigerators offered as type 1

refrigerators under the classification in interim Federal

Specification AA-R-00211d were procured from civilian retail

sources as required. This involved preparation of a written

justification for a "No-Bid” purchase to avoid disclosure of

the purchaser. These refrigerators were picked up by NBS

personnel on April 3* thus assuring that they were furnished

through regular trade channels. No disclosure of their intended

use was made to any supplier. The four makes purchased were:

Frigidaire (Model S-124-57)

Admiral (Model DAI36 O)

Westinghouse (Model SK-115)

Coldspot (Model L12-A)
'
5

The purpose of the requested tests was twofold: first, to

determine if the interim Federal Specification AA-R-00211d,

would permit selection of commercially-produced refrigerators of

adequate quality; and second, to determine the cost and time

requirements for making the tests in the subject specification.

The test room and its temperature and humidity controlling

equipment were about one-third finished at the beginning of this

quarter. The refrigerating system (two 5-ton compressors, one

air handler and related equipment), the control system

(one circular chart recorder, one proportioning relay, motorized

step controller, starters and solenoid valves) and the

humidification setup were installed by June 15. There was

some delay during this period due to inability to obtain

certain necessary repair parts although all major items were

on hand.

On June 17 the first test runs with the Frigidaire were

started. The tests describedin the interim Federal Specification

were continued in succession until July 3 when it was found that

the refrigerator under test failed to reduce the general food

storage compartment temperature below 43F at 110F ambient

temperature. Since the refrigerator under test was a type

1 unit, this raised the question of whether the evaporator

(chiller) compartment should have been loaded with simulated

frozen food for the capacity tests. The frozen food was

removed from the chiller and the complete series of tests was

started over.

It is expected that the performance tests of the four

refrigerators can be completed within the next reporting quarter.

A conference was held at NBS in June 1957^ between

Mr. Paul Vogel, of QMR & EC, Mr. Frank W. Reinhart, Chief,

Organic Plastics Section, NBS, and Mr. W. F. Goddard and

Mr. C. W. Phillips, Air Conditioning, Heating, and Refrigeration

Section, NBS, to clarify questions posed by industry relative

to the plastics requirements of the subject specifications.

Project Cost Breakdown

The project costs for this reporting quarter are given in

the accompanying invoice prepared by the Accounting Division.

The itemized figures listed herein are the approximate

expenditures for the five main items under investigation

during the quarter.
mmi
- 6 -

Cost Breakdown by Object

Labor $ 8095

Material 1325

Equipment 492

Misc. Services* 1367

Bureau Supervision 2348

Total $13627

*Travel, Shipping, Communications, Photos., etc.

Cost Breakdown by Project

Project Percent of Total Cost

Exhaust Gas Heat -Exchanger 20%

Kentucky Trailers

Refrigerated Structures

Metering Heat Sink

60%

Refrigerator Specification 20%

At the close of Fiscal Year 1957 approximately $6000

remained on hand under Order 57-21, subject to about $400 of

unliquidated obligations.

U. S. DEPARTMENT OF COMMERCE

Sini'luir \V erks, Secretary

NATIONAL UUKEAU OK STANDARDS

A. V'. Astin, Director THE NATIONAL BUREAU OF STANDARDS

The scope of activities of the National Bureau of Standards at its headquarters in Washington,

D. C., and its major field laboratories in Boulder, Colorado, is suggested in the following listing of

the divisions and sections engaged in technical work. In general, each section carries out spe- cialized research, development, and engineering in the field indicated by its title. A brief

description of the activities, and of the resultant reports and publications, appears on the

inside front cover of this report.

WASHINGTON, I). C.

Electricity and Electronics. Resistance and Reactance. Electron Tubes. Electrical Instruments. Magnetic Measurements. Dielectrics. Engineering Electronics. Electronic Instrumentation.

Electrochemistry.

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

Technology. L^pgth. Engineering Metrology.

Heat and Power. Temperature Physics. Thermodynamics. Cryogenic Physics. Rheology

and Lubrication. Engine Fuels.

Atomic and Radiation Physics. Spectroscopy. Radiometry. Mass Spectrometry. Solid State Physics. Electron Physics. Atomic Physics. Nuclear Physics. Radioactivity. X-rays. Betatron. Nucleonic Instrumentation. Radiological Equipment. AEC Radiation Instruments,

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 Controls.

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.

Metal Physics.

Mineral Products. Engineering Ceramics. Glass. Refractories. Enameled Metals. Concreting

Materials. Constitution and Microstrueture

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 Mathematical Physics.

Data Processing Systems SEAC Engineering Group. Components and Techniques. Digital

Circuitry. Digital Systems. Analogue Systems. Application Engineering.

• Office of Basic Instrumentation * Office ol Weights and Measures

BOULDER, COLORADO

Cryogenic Engineering. Cryogenic Equipment. Cryogenic Processes. Properties of Materials.

Gas Liquefaction.

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

Propagation Services. Sun-Earth Relationships.

Radio Propagation Engineering. Data Reduction Instrumentation. Modulation Systems.

Navigation Systems. Radio Noise. Tropospheric Measurements. Tropospheric Analysis. Radio

Systems Application Engineering.

Radio Standards. Radio Frequencies. Microwave Frequencies. High Frequency Electrical

Standards. Radio Broadcast Service. High Frequency Impedance Standards. Calibration

Center. Microwave Physics. Microwave Circuit Standards.