Thermionics for Hypersonics

We propose to develop a design for thermionic devices that integrate directly into hypersonic vehicles. Thermionic energy conversion has the potential to leapfrog competing technologies but has largely been neglected for decades. Using our existing devices as a baseline, we propose to develop a new design that is compatible with harvesting heat directly through the scramjet liner, relying on existing thermal pathways that simultaneously cool the engine while preheating fuel. To meet this need, we propose two core innovations to address the largest integration challenges we have identified through discussions within the Air Force and elsewhere, in order to ease both the thermal and mechanical integration in this application.