Deployable, Compact Composite Radiators for Surface Power Generation

To enable the use of kilowatt class Fission Power Systems for surface missions to the moon and Mars Roccor proposes the development of a flat, titanium/water heat pipe with an integrated deployable composite radiator. The proposed design leverages Roccor’s experience in high strain composite deployable structures and two-phase thermal management products for spacecraft applications. Heat pipes currently provide a highly conductive passive heat transfer solution, but traditional heat pipes are cumbersome to interface to the Stirling engine and radiator panels and difficult to bend to proper configurations. While the current state-of-art is able to handle the heat load, NASA has identified deployability and thermal interfaces as focus areas for future thermal radiators. Roccor proposes to utilize their FlexCool thin flat heat pipes coupled with ROCool flexible conductive materials (k>1,000 W/m-K), and with enough strain energy to passively deploy a novel integrated Kilopower radiator.Roccor’s thin, flat FlexCool heat pipes can interface to flat surface with low thermal resistance, provide improved radiator fin efficiency, and are simple to bend. FlexCool will also be coupled with ROCool highly conductive (k>1,000 W/m-K) flexible blanket materials that uses proprietary processes to laminate pyrolytic graphite into a composite radiator materialThe overarching Phase I objective is to demonstrate the technical feasibility of the proposed heat pipe/radiator, and conduct a preliminary design-analysis-fabrication loop for a 200-watt panel capable of meeting the requirements for Sunpower’s current 80W Stirling engine technology. The maturation of this technology would enable the use of fission power systems larger than 1 kWe which would enhance current mission capabilities.