Testing of a Microchannel Partial Condenser and Phase Separator in Reduced Gravity

Abstract

Heat exchange has been successfully integrated with microchannel phase separation concepts to produce devices capable of simultaneous partial condensation and phase separation in reduced gravity. An air-cooled microchannel condenser has been tested on NASA’s KC-135 reduced gravity aircraft. The condenser was fed a mixture of air and water vapor at 70–95°C, which was cooled to below 40°C thereby generating water condensate. The condensate was successfully collected and removed as a separate stream over a range of operating conditions, thereby achieving simultaneous condensation and phase separation. Ambient air was used to cool in cross-flow with inches of water pressure drop. The microchannel device is presented along with an explanation of the principles of operation. Phase separation effectiveness and heat exchanger performance are reported for reduced gravity testing. Heat fluxes, effectiveness, and overall heat transfer coefficients are reported.