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The Spacecraft Radiative Thermal Model Exchange System is a technology developed for the bi-directional exchange of spacecraft radiative thermal models via the TMG thermal software package. It provides a means for quickly and accurately transferring models between TMG and theree of the major thermal radiation codes used in the spacecraft industry, particularly the ESARAD and Thermica packages, which are widely used by contractors to the European Space Agency, and the TSS code which is prevalent in the United States space industry. In order to reconcile element-based and primitives-based modeling approaches, this system includes an interactive primitives-based modeling system, enabling users to construct, import, and manipulate primitives-based radiation models in TMG.

This paper describes the development and testing status of several novel components and integration tools for space-based cryogenic applications. These advanced devices offer functionality in the areas of cryogenic thermal switching, cryogenic thermal transport, cryogenic thermal storage, and cryogenic integration. As such, they help solve problems associated with cryocooler redundancy, across-gimbal thermal transport, large focal plane array cooling, fluid-based cryogenic transport, and low vibration thermal links. The devices discussed in the paper include a differential thermal expansion cryogenic thermal switch, an across-gimbal thermal transport system, a cryogenic loop heat pipe, a cryogenic capillary pumped loop, a beryllium cryogenic thermal storage unit, a high performance flexible conductive link, a kevlar cable structural support system, and a high conductance make-break cryogenic thermal interface.

This paper describes the flight verification of a nitrogen triple-point Cryogenic Thermal Storage Unit (CTSU), which flew as part of the CRYOTSU payload on STS-95 in late 1998. The CTSU flight unit is a dual-volume device with a 140 cc beryllium cryogenic heat exchanger and a 17 liter stainless steel ambient storage tank. During the flight, the CTSU demonstrated 3 kJ of energy storage at 63.15 K with variable heat loads from 5-9 W. An additional test was performed which demonstrated nitrogen's solid-solid transition at 35 K with 1 kJ of energy storage. The zero-g environment had no measurable impact on CTSU operation.

This paper describes the Cryogenic Thermal Storage Unit (CTSU) flight experiment, which flew as part of the CRYOTSU payload on STS-95 in late 1998. The CTSU flight unit is a dual-volume nitrogen triple-point device with a 140 cc beryllium cryogenic heat exchanger and a 17 liter stainless steel ambient storage tank. During the 9-day flight, the CTSU completed all testing goals including 22 full freeze-thaw and 18 partial freeze-thaw cycles at power levels from 5-9 W. All tests were successful and demonstrated 3000 J of energy storage at 63.15 K. An additional test was performed which demonstrated nitrogen’s solid-solid transition at 35 K with 1000 J of energy storage. The zero-g environment had no discernible impact on CTSU operation.

This paper introduces the concepts utilized for the integration of a cryogenic capillary pumped loop into a flight experiment. The Cryogenic Capillary Pumped Loop (CCPL) version V, which was recently manufactured (9/97), is to be integrated into the Cryogenic Thermal Storage Unit (CRYOTSU) flight experiment as a secondary experiment. CRYOTSU, a Get-Away-Special (GAS) Can experiment, is currently manifested on STS-95 with an anticipated launch date of October 1998. The CCPL uses nitrogen as the working fluid with a 70-120 K operating temperature. The primary benefit of the CCPL is as a heat transport device in cryogenic bus systems. The primary issue of structurally supporting the CCPL while reducing parasitic heat loads will be detailed.