Advanced 50-kW Thermal Management System Demonstration

This proposal addresses the need for a compact thermal management system for cooling of high-heat-flux surfaces of DEW weapons systems which uses polyalfaolefin (PAO) fluid to transport system heat to ram air. TIAX proposes to develop a compact thermal management system technology based on the use of carbon dioxide refrigerant and the direct use of CO2 refrigerant and the PAO coolant for the two temperature levels required to be cooled. CO2 has numerous advantages, including excellent refrigerant heat transfer properties, high vapor density for compact piping and equipment size, heat rejection profile which will allow PAO and ram air flow rate about half of what would be required for conventional refrigerants, and it is nonflammable, nontoxic, and environmentally friendly. Use of TIAX¡¦s scroll work-recovery expansion technology with such a system will ensure that its power input is consistent with weapons platform needs. Direct use of the CO2 refrigerant and the required PAO fluid in the high heat flux interface with DEW weapons will simplify the system and assure small size. Refrigerated CO2 will be used for 30 C cooling loads, while PAO of the heat rejection loop will be used for 100 C cooling loads.