A Two-Phase Thermal Management System for the Space Station

The central thermal management system for the proposed NASA Space Station will likely employ a two-phase thermal bus to satisfy the high power and long transport distance requirements. Significant potential weight and power savings accrue from this approach. A pumped two-phase cooling loop is described that can meet the requirements while maintaining constant heat source temperatures with large power and sink temperature turndown capability. Predicted performance of the 25 kW ammonia flight conceptual design is presented along with test results from a Freon 114 test loop which confirms predicted characteristics.