INVESTIGATION OF NOVEL WORKING FLUIDS FOR USE IN SPACECRAFT HEAT PIPES

IN ORDER TO UTILIZE A WORKING FLUID FOR A SPECIFIC HEAT PIPE APPLICATION THE WORKING FLUID MUST HAVE A USEFUL TEMPERATURE RANGE THAT SPANS THE TEMPERATURE LIMITS OF THE HEAT PIPE. AN OVERVIEW OF THE STATUS OF CURRENT HEAT PIPE WORKING FLUIDS SHOWS THAT NONE OF THE CURRENT WORKING FLUIDS CAN BE USED OVER THE 450-700 K TEMPERATURE RANGE. BY PREDICTING THE LIQUID TRANSPORT FACTOR OF VARIOUS COMPOUNDS SEVERAL NOVEL WORKING FLUIDS WERE FOUND THAT CAN BE USED OVER THE 450-700 K TEMPERATURE RANGE. THE LIQUID TRANSPORT FACTOR HAS A PRONOUNCED EFFECT ON HEAT PIPE DESIGN. THE PROPOSED STUDY WILL EXPERIMENTALLY VERIFY THE PROPERTIES USED IN THE PREDICTION OF THE LIQUID TRANSPORT FACTOR OF THE NOVEL COMPOUNDS. THESE PROPERTIES ARE THE LIQUID DENSITY, LIQUID SURFACE TENSION, AND LIQUID VISCOSITY. IN ADDITION, THE THERMAL STABILITY AND CORROSIVE PROPERTIES OF THE NOVEL FLUIDS WILL BE DETERMINED. THIS WORK WILL DETERMINE THE FEASIBILITY OF USING THESE COMPOUNDS AS HEAT PIPE WORKING FLUIDS.