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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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At least 199 records · Page 11

The International Space Station's Multi-Purpose Logistics Module, Thermal Performance of the First Five Flights

The Multi-Purpose Logistics Module is the primary carrier for transport of pressurized payload to the International Space Station. Performing five missions within a thirteen month span provided a unique opportunity to gather a great deal of information toward understanding and verifying the orbital performance of the vehicle. This paper will provide a brief overview of the hardware history and design capabilities followed by a summary of the missions flown, resource requirements and possibilities for the future.

Holladay, Jon↗

Arrays of High Performance Thermal Detectors

Thermal detectors have historically been the sensors of choice for applications where photoconductive or photovoltaic detectors are unavailable. While they have the advantage of broad wavelength coverage, a primary disadvantage has been sensitivity; at a given operating temperature, bolometers are typically much less sensitive than photodetectors. The development of cryogenic bolometers has resulted in thermal detectors which can reach fundamental sensitivity limits. When operated at temperatures below 0.3 K these devices can provide background-limited sensitivity for cryogenic imaging and spectroscopy in space. The past decade has seen a rapid growth in sensitivity and array format in cryogenic bolometers. Micromachining technology, combined with advances in superconducting electronics, provides a strong technological base for future developments. I will describe the present state of development of low-temperature thermal detectors, and the possible extension of this technology to higher temperature operation.

Moseley, Harvey↗

Apparatus and Method for Thermal Performance Testing of Pipelines and Piping Systems

A test apparatus and method of its use for evaluating various performance aspects of a piping segment locates a piping segment between two cold boxes. A first cold box conditions test fluid before providing the fluid into the piping segment- The first and second cold boxes both significantly reduce, if not eliminate, any heat transfer from the ends of the piping so that accurate measurements of heat leak rates from the sides of the piping segment may be determined.

Fesmire, James E.↗

Effect of gravity opientation on the thermal performance of Stirling-type pulse tube cryocoolers

This paper extends the investigation of angular orientation effects to the refrigeration performance of high frequency (-40 Hz) Stirling-type pulse tube cryocoolers typical of those used in long-life space applications. Strong orientation effects on the performance of such cryocoolers have recently been observed during system-level testing of both linear and U-tube type pulse tubes. To quantify the angular dependency effects, data have been gathered on both U-tube and linear type pulse tubes of two different manufacturers as a function of orientation angle, cold-tip temperature, and compressor stroke.

angular dependency↗

Thermal Performance of High Temperature Titanium -- Water Heat Pipes by Multiple Heat Pipe Manufacturers

Titanium - water heat pipes are being investigated for use in heat rejection systems for lunar and Mars fission surface power systems. Heat pipes provide an efficient and reliable means to transfer heat to a radiator heat rejection system. NASA Glenn Research Center requisitioned nine titanium water heat pipes from three vendors. Each vendor supplied three heat pipes 1.25 cm diameter by 1.1 meter long with each vendor selecting a different wick design. Each of the three heat pipes is slightly different in construction. Additional specifications for the heat pipes included 500 K nominal operating temperature, light weight, and freeze tolerance. The heat pipes were performance tested gravity-aided, in the horizontal position and at elevations against gravity at 450 K and 500 K. Performance of the three heat pipes is compared. The heat pipe data will be used to verify models of heat pipe radiators that will be used in future space exploration missions.

Sanzi, James L.↗

Thermal Performance of High Temperature Titanium-Water Heat Pipes by Multiple Heat Pipe Manufacturers

Titanium-water heat pipes are being investigated for use in heat rejection systems for lunar and Mars fission surface power systems. Heat pipes provide an efficient and reliable means to transfer heat to a radiator heat rejection system. NASA Glenn Research Center requisitioned nine titanium water heat pipes from three vendors. Each vendor supplied three heat pipes 1.25 cm diameter by 1.1 meter long with each vendor selecting a different wick design. Each of the three heat pipes is slightly different in construction. Additional specifications for the heat pipes included 500 K nominal operating temperature, light weight, and freeze tolerance. The heat pipes were performance tested gravity-aided, in the horizontal position and at elevations against gravity at 450 and 500 K. Performance of the three heat pipes is compared. The heat pipe data will be used to verify models of heat pipe radiators that will be used in future space exploration missions.

Sanzi, James L.↗

Thermal Performance Expectations of the Advanced Stirling Convertor Over a Range of Operating Scenarios

The Advanced Stirling Radioisotope Generator (ASRG) will enable various missions such as small body sample return, atmospheric missions around Venus, as well as long - duration deep space missions. Analysis of the temperature distributions are performed on an Advanced Stirling Convertor, and the results are compared with available experimental measurements. This analysis includes applied environmental conditions that are similar to those that will be experienced while the convertor is in operation. The applied conditions represent a potential mission profile including pre-takeoff sterilization, launch, transit, and return. The results focus on the anticipated peak temperatures of the magnets in the linear alternator. These results confirm that the ASC can support future missions to deep space targets, extreme environment landers, as well as more conventional goals.

Reid, Terry V.↗

Thermal Performance Expectations of the Advanced Stirling Convertor Over a Range of Operating Scenarios

Objectives of this work are: (1) Assist the Science Mission Directorate in developing technologies for space missions. (2) Explore the capability of computational modeling to assist in the development of the Advanced Stirling Convertor. (3) Baseline computational simulation with available experimental data of the ASC. (4) Calculate peak external pressure vessel wall temperatures and compare them with anticipated values. (5) Calculated peak magnet temperature inside the ASC over a range of operational scenarios.

Reid, Terry V.↗

Infrared telescope (IRT) system cryogenic performance

Thermal performance evaluation tests on the Small Helium Cooled Infrared Telescope (IRT), prior to flight on Spacelab 2 in 1985, are reported. The telescope is a joint project of the Smithsonian Astrophysical Observatory, the University of Arizona, and the NASA-Marshall Space Flight Center. Starting with 190 liters of liquid helium to be converted to superfluid, 140 liters should be available at launch; 100 liters would be available 48 hours into the mission when first observations begin and 30 liters should be left as a reserve at payload deactivation. New data and insight have been gained regarding the processes which govern the functioning of a porous plug phase separator for superfluid helium.

Urban, E. W.↗

A Study of the Effects of Altitude on Thermal Ice Protection System Performance

Thermal ice protection systems use heat energy to prevent a dangerous buildup of ice on an aircraft. As aircraft become more efficient, less heat energy is available to operate a thermal ice protections system. This requires that thermal ice protection systems be designed to more exacting standards so as to more efficiently prevent a dangerous ice buildup without adversely affecting aircraft safety. While the effects of altitude have always beeing taked into account in the design of thermal ice protection systems, a better understanding of these effects is needed so as to enable more exact design, testing, and evaluation of these systems.

Addy, Harold E., Jr.↗

A Study of the Effects of Altitude on Thermal Ice Protection System Performance

Thermal ice protection systems use heat energy to prevent a dangerous buildup of ice on an aircraft. As aircraft become more efficient, less heat energy is available to operate a thermal ice protections system. This requires that thermal ice protection systems be designed to more exacting standards so as to more efficiently prevent a dangerous ice buildup without adversely affecting aircraft safety. While the effects of altitude have always beeing taked into account in the design of thermal ice protection systems, a better understanding of these effects is needed so as to enable more exact design, testing, and evaluation of these systems.

thermal ice protection system↗