Application Of Refrigerant Mixtures For Space Space Thermal Management

In a Small Business Innovation Research (SBIR) effort with Marshall Space Flight Center (MSFC), Foster-Miller, Inc., of Waltham, Massachusetts, has identified ways to utilize waste heat and to reduce thermal management system weight for manned space-flight applications.

The contract has resulted in a list of accomplishments. Initially, Foster-Miller constructed a heat pump heater for crew hygiene water: the pump, utilizing waste heat from the thermal bus, reduced water-heating power requirements from 5 kilowatts to 100 watts. The company then developed a proprietary oil-refrigerant separator for use in microgravity--a key component for the use of heat pumps in space. Next came the design and testing of a two-phase spacecraft thermal bus that employed a binary refrigerant mixture. The unique control system developed for the thermal bus resulted in an 85-percent decrease in pumping water.

As a result of its efforts, Foster-Miller has developed unique expertise in the fields of refrigerant chemistry and application engineering. At the same time, the company has established itself as a world-class developer of vapor compressor systems and equipment for novel applications.

Research and development activities concern various government agencies. For NASA, efforts entail the design, fabrication, and testing of a high-lift heat pump for future lunar and Mars explorations, along with the investigation of modular heat pumps for manned and unmanned space flights. Other government applications include multiple tasks for the Department of Defense. One deals with refrigerant replacement for silo-based missile guidance systems, and another focuses on microclimate and man-portable personal cooling systems.

Commercial applications of the product include engineering and consultation for the electric utility and supermarket industries to develop and test replacements for ozone-depleting refrigerants for commercial refrigeration and the development of a refrigerant mixture replacement for R-12 in automotive air-conditioning.