APPLICATION OF TWO-PHASE FLOW AND HEAT TRANSFER CORRELATIONS TO ZERO GRAVITY CONDITIONS

THE PROPOSED RESEARCH PROGRAM IS FOR DEVELOPMENT OF MODELS FOR TWO-PHASE FRICTION MULTIPLIER, VOID FRACTIN-QUALITY RELATION, AND FORCED CONVECTIVE NUCLEATE BOILING HEAT TRANSER COEFFICIENT UNDER ZERO GRAVITY CONDITIONS. DUE TO HIGH HEAT TRANSFER CO EFFICIENT, A TWO-PHASE GAS-LIQUID MEDIUM IS EXPECTED TO BE USED IN THE FUTURE COOLING SYSTEMS FOR SPACECRAFT EQUIPMENT. DESIGN OF THESE COOLING SYSTEMS REQUIRE A KNOWLEDGE OF TWO-PHASE FLOW AND HAT TRANSFER UNDER REDUCED AND ZERO GRAVITIES. THE OBJECTIVE OF THE PROPOSED PROGRAM IS TO EXTEND THE WELL ESTABLISHED TWO-PHASE FLOW MODELS DEVELOPED AT EARTH GRAVITY TO ZERO GRAVITY CONDITIONS. THIS IS ACHIEVED BY USING THE REDUCED GRAVITY POOL BOILING AND BUBBLE DYNAMIC STUDIES TO ESTABLISH THE EXPECTED VOID DISTRIBUTION IN TWO-PHASE FLOW MODELS IN WHICH THE GRAVITY COMPONENT HAS BEEN NEGLECTED OR CAN BE EASILY SEPARATED WILL BE USED TO FORMULATE THE MODELS FOR THE ABOVE THREE MAJOR ENGINEERING PARAMETERS.