Ying Sun
University of Cincinnati
High-temperature spacecraft radiators are required to accommodate thermal control of nuclear power and propulsion systems for long-distance space manned missions. Meanwhile, the radiators need to be lighter than the state-of-the-art to minimize power consumption. To address these needs, this project will develop and demonstrate a high-temperature, lightweight spacecraft radiator with 3D-printed titanium loop heat pipes (LHP) and titanium-encapsulated pyrolytic graphite fins to simultaneously improve thermal performance and mechanical robustness for sustainable heat dissipation of nuclear propulsion systems. LHPs, capable of reliably operating over long distances, will significantly simplify and enable flexible designs of the pumped flow loop, heat pipes, and radiator integration with single, connected structures, minimizing joints and improving reliability. The all-Ti LHP evaporator assembly will be 3D printed using direct metal laser sintering to minimize interfacial thermal resistances and mismatch in the coefficient of thermal expansion. Replacing the knife-edge seal with a printed cap, the long-term robustness of the 3D-printed LHPs will be significantly improved at reduced manufacturing cost. The radiator fins consisting of a highly conductive, lightweight pyrolytic graphite core encapsulated by an ultra-thin Ti matrix with solar UV-Vis protection coating will achieve the best aerial density, thermal performance, mechanical robustness, and reliability. The integrated radiator panel will deliver effective and reliable heat rejection for future nuclear-powered space missions.
