Enhanced recuperation cycle for aircraft powerplant turbine engine

A powerplant for an aircraft, comprising:

• a rotating assembly including a compressor rotor and a turbine rotor;
• a combustor;
• a fuel-air heat exchanger;
• a recuperator;
• a flowpath extending longitudinally from an airflow inlet into the flowpath, sequentially across the compressor rotor, through the fuel-air heat exchanger, through the recuperator, through the combustor and across the turbine rotor, to combustion products exhaust from the flowpath;
• and
• a fuel delivery system including a fuel source, a fuel circuit, a fuel injector, the fuel circuit configured to deliver fuel received from the fuel source to the fuel injector, the fuel circuit extending through the fuel-air heat exchanger between the fuel source and the fuel injector, and the fuel injector configured to inject the fuel into the combustor;
• wherein the fuel delivery system further includes a recirculation circuit, an inlet into the recirculation circuit is fluidly coupled to the fuel circuit downstream of the fuel-air heat exchanger along the fuel circuit, and an outlet from the recirculation circuit is fluidly coupled to the fuel circuit upstream of the fuel-air heat exchanger along the fuel circuit.

A powerplant for an aircraft, comprising:

• a fuel-air heat exchanger;
• a compressor section;
• a recuperator;
• a combustor section comprising a combustor;
• a turbine section;
• a flowpath extending from an airflow inlet into the flowpath, through the fuel-air heat exchanger, the compressor section, the recuperator, the combustor section and the turbine section, to a combustion products exhaust from the flowpath;
• and
• a fuel delivery system including a fuel source, a fuel circuit, a fuel injector and a fuel turbine, the fuel circuit configured to direct fuel received from the fuel source, across the fuel-air heat exchanger, to the fuel injector, the fuel injector configured to inject the fuel into the combustor section for combustion within the combustor, and fuel delivery system configured to expand the fuel across the fuel turbine along the fuel circuit between the fuel source and the fuel-air heat exchanger.