Abstract: Turbine engine systems are described. The turbine engine systems include a combustor arranged along a core flow path of the turbine engine, a cryogenic fuel tank configured to supply a fuel to the combustor, a fuel supply line having a first flow supply line and a second flow supply line, the first flow supply line fluidly connecting the cryogenic fuel tank to the combustor through a first core flow path heat exchanger, and the second flow supply line fluidly connecting the cryogenic fuel tank to the combustor through a second core flow path heat exchanger, and a flow controller arranged along the fuel supply line and configured to respectively control a flow of fuel into the first flow supply line and the second flow supply line.

Abstract: Turbine engine systems are described. The turbine engine systems include a combustor arranged along a core flow path of the turbine engine, a cryogenic fuel tank configured to supply a fuel to the combustor, a fuel supply line having a first flow supply line and a second flow supply line, the first flow supply line fluidly connecting the cryogenic fuel tank to the combustor through a first core flow path heat exchanger, and the second flow supply line fluidly connecting the cryogenic fuel tank to the combustor through a second core flow path heat exchanger, and a flow controller arranged along the fuel supply line and configured to respectively control a flow of fuel into the first flow supply line and the second flow supply line.

Abstract: Waste heat management systems are described. The waste heat management systems include a turbine engine having a compressor section, a combustor section, a turbine section, and a nozzle. The compressor section, the combustor section, the turbine section, and the nozzle define a core flow path that expels through the nozzle. The waste heat management systems also include an auxiliary power unit (APU) system and a waste heat recovery system operably connected to the APU system. The APU system is integrated into a working fluid flow path of the waste heat recovery system.

Abstract: Aircraft propulsion systems and aircraft having such propulsion systems are described. The aircraft propulsion systems include a fan, a motor operably connected to the fan by a drive shaft, and an aircraft power generation system operably coupled to the motor to drive rotation of the fan through the drive shaft, wherein the aircraft power generation system comprises a fuel cell configured to generate at least 1 MW of electrical power.

Abstract: Gas turbine engines are described. The gas turbine engines include a compressor section, a combustor section, a turbine section, and a nozzle, wherein the compressor section, the combustor section, the turbine section, and the nozzle define a core flow path that expels through the nozzle. A waste heat recovery system is operably connected to the gas turbine engine, the waste heat recovery system having a working fluid. An auxiliary cooling system is configured to provide cooling to a working fluid of the waste heat recovery system.

Abstract: Gas turbine engines are described. The gas turbine engines include a compressor section, a combustor section, a turbine section, a nozzle section, wherein the compressor section, the combustor section, the turbine section, and the nozzle section define a core flow path that expels through the nozzle section, and a waste heat recovery system. The waste heat recovery system includes a heat recovery heat exchanger arranged at the nozzle section, wherein the heat recovery heat exchanger is arranged within the nozzle section such that the heat recovery heat exchanger occupies less than an entire area of an exhaust area of the nozzle section and a heat rejection heat exchanger arranged to reduce a temperature of a working fluid of the waste heat recovery system.

Abstract: Gas turbine engines are described. The gas turbine engines includes a compressor section, a combustor section, a turbine section, and a nozzle section. The compressor section, the combustor section, the turbine section, and the nozzle section define a core flow path that expels through the nozzle section. A cooling duct is provided that is separate from the core flow path. A waste heat recovery system is arranged with a heat rejection heat exchanger arranged within the cooling duct and a blower is arranged within the cooling duct and configured to generate a pressure drop across the heat rejection heat exchanger.

Abstract: Turbine engine systems are described. The turbine engine systems include a combustor arranged along a core flow path of the turbine engine, a cryogenic fuel tank configured to supply a fuel to the combustor, a fuel supply line having a first flow supply line and a second flow supply line, the first flow supply line fluidly connecting the cryogenic fuel tank to the combustor through a first core flow path heat exchanger, and the second flow supply line fluidly connecting the cryogenic fuel tank to the combustor through a second core flow path heat exchanger, and a flow controller arranged along the fuel supply line and configured to respectively control a flow of fuel into the first flow supply line and the second flow supply line.

Abstract: Aircraft propulsion systems and aircraft having such propulsion systems are described. The aircraft propulsion systems include a fan, a motor operably connected to the fan by a drive shaft, and an aircraft power generation system operably coupled to the motor to drive rotation of the fan through the drive shaft, wherein the aircraft power generation system comprises a fuel cell configured to generate at least 1 MW of electrical power.

Abstract: Waste heat management systems are described. The waste heat management systems include a turbine engine having a compressor section, a combustor section, a turbine section, and a nozzle. The compressor section, the combustor section, the turbine section, and the nozzle define a core flow path that expels through the nozzle. The waste heat management systems also include an auxiliary power unit (APU) system and a waste heat recovery system operably connected to the APU system. The APU system is integrated into a working fluid flow path of the waste heat recovery system.

Abstract: Gas turbine engines are described. The gas turbine engines include a compressor section, a combustor section, a turbine section, and a nozzle, wherein the compressor section, the combustor section, the turbine section, and the nozzle define a core flow path that expels through the nozzle. A waste heat recovery system is operably connected to the gas turbine engine, the waste heat recovery system having a working fluid. An auxiliary cooling system is configured to provide cooling to a working fluid of the waste heat recovery system.

Abstract: Gas turbine engines are described. The gas turbine engines includes a compressor section, a combustor section, a turbine section, and a nozzle section. The compressor section, the combustor section, the turbine section, and the nozzle section define a core flow path that expels through the nozzle section. A cooling duct is provided that is separate from the core flow path. A waste heat recovery system is arranged with a heat rejection heat exchanger arranged within the cooling duct and a blower is arranged within the cooling duct and configured to generate a pressure drop across the heat rejection heat exchanger.

Abstract: Gas turbine engines are described. The gas turbine engines include a compressor section, a combustor section, a turbine section, a nozzle section, wherein the compressor section, the combustor section, the turbine section, and the nozzle section define a core flow path that expels through the nozzle section, and a waste heat recovery system. The waste heat recovery system includes a heat recovery heat exchanger arranged at the nozzle section, wherein the heat recovery heat exchanger is arranged within the nozzle section such that the heat recovery heat exchanger occupies less than an entire area of an exhaust area of the nozzle section and a heat rejection heat exchanger arranged to reduce a temperature of a working fluid of the waste heat recovery system.