THERMAL MANAGEMENT IS ONE OF THE MOST IMPORTANT CHALLENGES IN SPACE APPLICATIONS. THE SUCCESS OF SPACE EXPLORATION AND TRAVEL IS DIRECTLY TIED TO HOW WE EFFICIENTLY CONVERT TRANSFER AND STORE ENERGY IN ENERGY SYSTEMS SUCH AS MAINTAINING CRYOGENIC FLUIDS FOR PROPULSION PROTECTION OF VEHICLES FROM AERODYNAMIC HEATING AND MAINTAINING COMFORTABLE LIVING CONDITIONS FOR CREW. THIS ENERGY TRANSFER TAKES THE FORM OF HEAT ACQUISITION HEAT TRANSPORT AND HEAT REJECTION. AN EFFECTIVE THERMAL CONTROL SYSTEM MUST PROVIDE THESE THREE BASIC FUNCTIONS WHILE BEING MINDFUL OF THE OPERATIONAL ENVIRONMENT AND SPACECRAFT SYSTEM. AT THE HEART OF THIS ENERGY CONVERSION IS INTERFACIAL HEAT TRANSFER ESPECIALLY THAT BETWEEN SOLIDS AND LIQUIDS/GASES WHICH CAN BE SIGNIFICANTLY ENHANCED USING NANOTECHNOLOGY-ENABLED FUNCTIONALIZED SURFACES. FUNCTIONALIZED SURFACES WITH TAILORED THERMAL AND WETTABILITY PROPERTIES CAN BE FABRICATED USING FEMTOSECOND LASER SURFACE PROCESSING (FLSP)ENGINEERED SURFACE PROPERTIES ARE OBTAINED BY THE PRODUCTION OF SELF-ORGANIZED MICROSTRUCTURES COVERED BY LAYERS OF NANOPARTICLES. PRELIMINARY RESULTS USING SUCH SURFACES HAVE DISPLAYED VERY PROMISING HEAT TRANSFER PROPERTIES WITH EXTRAORDINARY SHIFTS OF THE LEIDENFROST TEMPERATURE AND ENHANCEMENT OF BOTH THE POOL BOILING HEAT TRANSFER COEFFICIENTS AND CRITICAL HEAT FLUX. THE OBSERVED EXTRAORDINARY HEAT TRANSFER IS ATTRIBUTED TO BOTH THE MICROSTRUCTURE AND THE PRESENCE OF SELF-ASSEMBLED NANOPARTICLES ON TOP OF THE MICROSTRUCTURES THROUGH THE COLLECTIVE CONTRIBUTIONS OF EFFECTIVE THERMAL CONDUCTIVITY HIGH LIQUID WETTING AND CAPILLARY WICKING HIGH NUCLEATION SITE DENSITY AND THE FORMATION OF NANOBUBBLES FROM THREE-DIMENSIONAL NANOCAVITIES.

Board Of Regents Of The University Of Nebraska

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