Large Format Ceramic Oscillating Heat Pipes

In response to NASA FY 2025 SBIR solicitation topic Z-ENABLE.01 “Enabling Power and Thermal Technologies”, scope “Advance Thermal Transport Technologies for Space Missions”, sub-system “Power Conversion System (PCS) Heat Transport” -- ThermAvant Technologies (TAT) proposes a ceramic oscillating heat pipe (OHP) solution to address two subcomponents: “Reactor to the power conversion system” and “Advanced Heat Exchangers at power conversion system interface”. High temperature heat acquisition and transport is a critical technology gap inhibiting implementation of nuclear energy propulsion (NEP). The development priority is reflected in the STMD 2024 Civil Space Shortfall report, with ID 709: Nuclear Electric Propulsion for Human Exploration at rank 8 of 187 technology areas. NEP requires the acquisition of MW-levels of heat at 1000-1400K from the reactor core, and transport to the power conversion system with temperature drop <150K. Alkali metal heat pipes 3-5 meters long are required. TAT has active NASA funding for development of metallic OHPs for this application and recently demonstrated the first known 3-meter heat pipe operating > 1000K (with SS316 envelope). There is potential to significantly improve reactor designs if large format neutron transparent envelopes (e.g. alumina) are manufacturable and reliable. Target markets: space and terrestrial nuclear heat pipe reactors