This Request for Information (RFI) from the Defense Advanced Research Projects Agency’s (DARPA) Microsystems Technology Office (MTO) seeks information on current capabilities and recent advances in thermal management technologies to enable sustained operation of microsystems in extreme environments.
Microsystems deployed within high-speed aircraft are subjected to high temperatures (>1,000 oC) on the vehicle surface and adjacent boundary layer due to aerodynamic heating. Significant attention has focused on thermal protection systems to ensure the structural and functional integrity of the vehicle and combustion chamber. These include vehicle integrated passive thermal protection systems (TPS) to cool leading edges based on scalable net-shape manufacturing and advanced thermal design. Passive and active thermal management concepts, coatings and materials also continue to be explored. Current TPS materials and technologies have focused on operation for limited durations (few seconds to minutes) under these conditions. Microsystems deployed within spacecraft also are exposed to surroundings temperature extremes during their orbit. Battery module temperatures have been estimated to vary from >50 oC to -191 oC in Earth’s orbit in the altitude range of 200 km – 35,786 km3 .
With increasing functionality expected from deployed microsystems in these air and space vehicles, waste heat management is a key challenge. Their sustained operation requires rejection of the >200 W of generated heat while the vehicle envelope is subjected to these extreme temperature surroundings. While thermal management technologies to reject high heat fluxes to terrestrial ambient environments have received significant attention, harsh thermal environments pose daunting challenges. Thermal management technologies to address these challenging requirements are key to increasing capabilities of deployed microsystems, with stringent size weight and power constraints. Systems level thermal management challenges for various types of high-speed air4 and space5 vehicles have been identified. Significant innovations in thermal management technologies are required to enable sustained operation of these microsystems.
The focus of this Request for Information (RFI) is to survey the state-of-the-art (SOA), and identify promising thermal management technologies, for high performance microsystems deployed within high-speed air or space vehicles, exposed to high temperature and/or high heat flux environments.
Responses to this RFI should be submitted to [email protected]. The due date for responses is October 30, 2023 at 5:00 p.m. (ET).