Description: High temperature heat acquisition and transport is a critical technology gap inhibiting full implementation of nuclear energy propulsion (NEP) and power sources for NASA inter-planetary and Lunar Surface missions. Nuclear energy thermal management requires acquisition and transport of 4-10MW of power at 1200-1400K; the target axial heat flux is 1.0MW/m2. Furthermore, NASA requires candidate technologies to transport heat 5-10 meters with a temperature drop below 150K. ThermAvant Technologies (TAT) proposes to develop an Oscillating Heat Pipe (OHP)-based structurally integrated long distance high-temperature heat acquisition and transport device to meet this crucial need. TAT will conduct an extensive performance and validation test program to quantify OHP manufacturing and operating metrics, and quantify advances over the current state of the art (SOTA). The OHP is an emerging innovative thermal management device which has proven to be size, weight and power consumption and cost (SWaP-C) competitive for a number of heat flux acquisition and transport aerospace applications. In view of SBIR Phase 1 program and resource constraints, TAT will develop proof of concept hardware fabricated from Inconel tubing - charged with sodium, potassium, or a sodium/potassium eutectic mixture to demonstrate and quantify OHP technology capabilities, see Figure 1. We expect to achieve the following analytical and performance innovations: Acquire and transport heat at 1300K a distance of 3 meters (>10X further than current SOTA OHP) Demonstrate axial heat flux greater than 1MW/m2, with target temperature drop less than 150K Extend and validate limits of operation to long transport configurations Experimentally validate OHP performance map in Q vs. T operational space Assess candidate OHP designs for Phase II hardware Recommend Phase 2 OHP based high-temperature heat acquisition and transport design

Benefits: NASA requires significant improvements over the state-of-the-art high temperature heat acquisition and transport to meet its ambitious Inter-planetary and Lunar Science portfolio. NASA requirements are up to acquire up to 10 MW of heat (heat flux up to 1MW/m2) at 1200K to 1400K and transport the heat over 5 meters with temperature drop no greater than 150K. The most significant near to mid- term mission infusion points are: Nuclear Electric Propulsion (NEP) Lunar Surface Nuclear Power Systems Planetary Exploration Missions

Acquisition, spreading, transport and rejection of high flux high temperature heat are significant thermal issues facing government and commercial applications. Nuclear power thermal management to meet high efficiency and clean energy needs High Temperature Electronics and Power Electronics Management of incident high energy at arbitrary locations (high heat flux strikes)