BINARY MIXTURES FOR SPACECRAFT HEAT TRANSPORT

THE PROPOSED CONCEPT PRESENTED HERE IS A NOVEL HEAT TRANSPORT LOOP FOR THERMAL MANAGEMENT HEAT REJECTION FROM SPACE VEHICLES. CURRENT WASTE HEAT REJECTION TECHNIQUES BEING CONSIDERED INCLUDE THE USE OF A SINGLE-PHASE LIQUID WATER LOOP FOR HEAT ACQUISITION WITHIN THE MODULES. THIS WATER LOOP INTERFACES WITH AN EXTERNAL SINGLE-PHASE LIQUID HEAT TRANSPORT LOOP WHICH CARRIES THE WASTE HEAT TO BODY MOUNTED RADIATORS FOR REJECTION TO SPACE. THE PROPOSED CONCEPT IS TO REPLACE THE EXTERNAL SINGLE-PHASE LIQUID WORKING FLUID WITH A NONAZEOTROPIC BINARY MIXTURE UTILIZING A TWO-PHASE PUMP. SEVERAL ADVANTAVAGES OVER BOTH A SINGLE-PHASE FLUID AND A TWO-PHASE PURE FLUID ARE OFFERED THROUGH THE USE OF A TWO-PHASE BINARY MIXTURE WORKING FLUID:NONISOTHERMAL PHASE CHANGE HIGH HEAT TRANSFER COEFFICIENTS HIGH HEAT OF VAPORIZATION LOW FLUID FLOW RATES COMPOSITION SHIFTING FOR TEMPERATURE AND CAPACITY CONTROL. THESE PROPERTIES LEAD TO POTENTIAL REDUCTIONS IN BOTH PUMPING POWER CONSUMPTION AND SYSTEM WEIGHT.