Quantitative leak test design guide
Calibrated enclosure technique for rapid and accurate determination of leak rates
LEAKAGE↗
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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Quantitative leak test design guide Final report, 8 Dec. 1966 - 7 Aug. 1967
Calibrated enclosure system using helium injection method for estimating leakage rates
Hollinger, P. L.↗
Foot-operated cell-counter
Cell-counter for cell indices consists of a footboard with four pressure sensitive switches and an enclosure for the components and circuitry. This device increases the operators efficiency by reducing the number of required hand movements.
Eisler, W. J., Jr.↗
Thermal radiation heat transfer. Volume 2 - Radiation exchange between surfaces and in exclosures
Thermal radiation exchange between surfaces and enclosures
Howell, J. R.↗
Secondary flow induced by a transverse resonant acoustic field in a circular duct.
Finite amplitude standing transverse resonant acoustic field effects upon flow behavior of viscous fluid in cylindrical enclosure to acoustically model combustion instability
Hribar, A. E.↗
Proceedings of the Second Workshop on Voltage Breakdown in Electronic Equipment at Low Air Pressure
The Second Workshop on Voltage Breakdown in Electronic Equipment at Low Air Pressure was sponsored by the Jet Propulsion Laboratory, Pasadena, California. It has been three and one-half years since the convening of the first workshop on voltage breakdown. In this interval, gains are evidenced in the progress and sophistication in solving voltage breakdown problems affecting electronic equipment operating at high altitudes or other low air pressure environments. Although space applications predominate the area of concern, other projects such as the SST are becoming increasingly involved with voltage breakdown. High-voltage breakdown in spacecraft continues; however, the incidences of occurrence appear to have decreased in spite of an increase in the number of missions flown. This, it is felt, is due to many project managers now requiring all equipment with voltage in excess of 270-V peak to be designed to operate in the critical pressure region without damage, even though its normal functional environment is sea level pressure and the hard vacuum of space. In addition, designers are becoming more aware of the principle of good high-voltage design by selecting void-free components, proper spacing of conductors, isolating high-voltage circuitry from lower voltage areas, etc. The consensus seems to be that the slight increase in cost to achieve a provable corona-free design is more than offset by the increase in confidence that the equipment will survive accidental loss of vacuum during high-vacuum tests, inadvertent turn on while passing through the critical air-pressure region of earth after launch or outgassing in flight pressurizing the enclosure into the critical pressure region.
E. R. Bunker, Jr.↗
The hemispherical thermal emittance of copper as a function of oxidation conditions
Thermal emittance of Cu measured in vacuum in spherical enclosure by calorimetric method to investigate oxidation effect
Coon, C. W.↗
Active cavity radiometer, type III - An automatic, absolute standard, highly accurate detector
Instrument of simple construction operates without vacuum enclosure over wide pressure range and temperatures from 218 to 398 deg K and defines absolute radiometric scale to within less than 0.5 mW/sq cm. It has potential application to meteorology and climatology and operates on electrical substitution calorimeter principle.
Willson, R. C.↗
Glass tube splitting tool
Tool accurately splits glass tubing so cuts are aligned 180 deg apart and reassembled tube forms low pressure, gastight enclosure. Device should interest industries using cylindrical closed glass containers.
Klein, J. A.↗
Radiant heat transfer to absorbing fluid media
Radiant heat transfer from heated cylindrical enclosure with black/gray walls to absorbing gas or gas having black particles, calculating absorption coefficients
Keng, E. Y. H.↗
Low noise electromagnetic flowmeter
Parasitic hum is removed by using an isophase magnetic field created within flowmeter and an enclosure which prevents leakage of flux field. Method prevents contamination of flow conduit and eliminates zero point drift.
Cushing, V. J.↗
Simple non-destructive tests for electroexplosive devices
Electrothermal behavior of bridgewire-explosive interface is defined by pulsing electroexplosive device with a safe level of current and examining the resistance variation of bridgewire. Bridgewire provides signal which describes average wire temperature and heat sinking to the explosive and enclosure.
Rosenthal, L. A.↗
Temperature and humidity control of simulated human breath
Subsystem was developed for breathing metabolic simulator which adjusts temperature and humidity of air to levels of human exhaled breath. Temperature-humidity subsystem is described, consisting of aluminum enclosure with 400 watt heat sheet glued to bottom, vertical separators, inlet connection, and check valve.
Bartlett, R. G.↗
An efficient prebreathing apparatus for humans during decompression
Portable prebreathing system was developed which recirculates and reconditions respiratorily exhaled oxygen. Apparatus reduces fire hazards, simplifies prebreathing procedures, and does not require extensive enclosure venting system usage.
Jaax, J. R.↗
Measurement of the gravitational redshift using a clock in an orbiting satellite
A hydrogen maser clock is proposed for enclosure in an orbiting satellite to measure the gravitational effect on time scales with high accuracy. This experiment is used to test the principle of equivalence for clocks in space. Extremely narrow linewidth of Fe-57 radiation and absorption due to Mossbauer effect over 75 ft vertical distance was used to confirm the prediction of the equivalence principle to 1 part in 100. The fractional frequency shift of a satellite-borne oscillator observed from earth is also given.
Vessot, R. F. C.↗
Experimental system for the control of surgically induced infections, operating and maintenance instructions D203613-004
An experimental portable system used to control surgically induced infections is described. The system consists of a portable clean room comprised of a laminar flow filter system consistent with Federal standards; a helmet-shoulder pad assembly; a communication system; a helmet ventilation system; a transparent walled enclosure; and surgical gowns. Guidelines for the set up and operation of such equipment are given along with corrective steps to use in case of system malfunctions. Cleaning procedures, maintenance requirements, and disassembly and transfer particulars are included.
Tevebaugh, M. D.↗
Nonmetallic-material configuration control in the Apollo spacecraft
The methods employed by NASA to establish configuration control of nonmetallic materials on Apollo spacecraft are described. A five step procedure for examining contractor materials for suitability and compatibility is presented. The compatibility of the materials with the oxygen enriched environment of the spacecraft enclosures is emphasized.
Steinthal, M. W.↗
Apollo spacecraft nonmetallic materials applications
The applications of nonmetallic materials to the structures of Apollo spacecraft are discussed. The spacecraft components are examined and the rationale behind the use of specific nonmetallic materials is presented. The emphasis is on the compatibility of the materials with the oxygen enriched atmosphere of the spacecraft enclosures.
Craig, J. W.↗