THE EFFECTS OF MICROGRAVITY ON TWO-PHASE FLOWS

TWO-PHASE FLOWS WILL BE EMPLOYED IN MANY OF THE POWER GENERATION AND THERMAL MANAGEMENT SYSTEMS CURRENTLY UNDER DEVELOPMENT OR PROPOSED FOR FUTURE APPLICATION IN SPACE. WHILE THE PHENOMENA OCCURRING IN TWO-PHASE FLOW HAVE BEEN STUDIED EXTENSIVELY FOR EARTH-BOUND SYSTEMS, RELATIVELY LITTLE IS KNOWN ABOUT THE EFFECTS OF MICROGRAVITY ON TWOPHASE FLOWS. AN ORGANIZED RESEARCH EFFORT IS NEEDED TO PERMIT THE DESIGN OF TWO-PHASE FLOW SYSTEMS FOR USE IN MICROGRAVITY. IN THE PHASE I EFFORT OF THE PROPOSED PROGRAM, A THOROUGH LITERATURE SURVEY WILL BE PERFORMED TO ASSESS THE CURRENT LEVEL OF UNDERSTANDING OF TWO-PHASE FLOWS IN MICROGRAVITY AS COMPARED TO THAT FOR TWO-PHASE FLOWS FOR EARTH-BASED SYSTEMS. THIS ASSESSMENT WILL BE SUPPLEMENTED BY ANALYSIS OF RESULTS ALREADY OBTAINED FOR EARTH-BOUND SYSTEMS TO DEVELOP A DETAILED EXPERIMENTAL PROGRAM PLAN. THIS TEST PLAN WILL INCLUDE EXPERIMENTS, TO BE PERFORMED IN FUTURE CONTRACT PHASES, DESIGNED TO ADVANCE THE STATE-OF-THE-ART FOR TWO-PHASE FLOWS IN MICROGRAVITY TO A LEVEL COMPARABLE TO THAT FOR TWO-PHASE FLOWS FOR EARTH-BOUND SYSTEMS.