US Patent 10443503 Fuel system for a gas turbine engine

A gas turbine fuel system including a main fuel line providing fuel flow from a fuel tank to a combustor, and at least one pump, including an ejector pump, pumping fuel from the fuel tank to the combustor via a fuel metering unit. The fuel metering unit directs a portion of the fuel into a motive flow line which returns a portion of the fuel to the ejector pump. First and second heat exchangers are disposed in serial flow communication within the main fuel line between the pump and the fuel metering unit. The first heat exchanger is a fuel-to-fuel heat exchanger.