LIQUID-HYDROGEN FUEL SYSTEM FOR AN AIRCRAFT

A fuel system having a hydrogen fuel tank for fueling a fuel feed and propulsion system. The fuel system having a jet pump within the hydrogen fuel tank, at least one primary pump receiving fuel from the jet pump and pressurizing fuel to an outlet path and a first fuel recirculation path configured to selectively recirculate fuel to the hydrogen fuel tank. The first fuel recirculation path is fluidly connected to the outlet path. The first fuel recirculation path includes a heat exchanger positioned within the hydrogen fuel tank to cool fuel received from at least one of the fuel feed system or a tank pressurization system. The heat exchanger and a Joule-Thomson expansion at the jet pump minimizes recirculated fuel temperature, which in combination with a selective flow recirculation rate improve the life of the primary pump downstream.