Mechanically driven air vehicle thermal management device

An aircraft power generation system, comprising:

• a gas turbine engine including a compressor section, a turbine section, and an engine shaft, the compressor section arranged in serial flow arrangement with the turbine section, and the engine shaft rotatable with at least a portion of the compressor section and with at least a portion of the turbine section;
• a reverse Brayton cycle system including a compressor, a first driveshaft, a turbine, and a first heat exchanger, wherein the first driveshaft is mechanically coupled with the compressor and the turbine;
• and
• a gearbox configured to receive mechanical energy from the engine shaft and transmit the mechanical energy to the reverse Brayton cycle system through the first driveshaft and to an electrical powertrain through a second driveshaft each separately coupled to the gearbox in a parallel arrangement, the electrical powertrain further coupled to a fan section in serial flow arrangement with the compressor section of the gas turbine engine, wherein the first driveshaft is configured to output a proportional rotational speed relative to a rotational speed of the engine shaft when the gas turbine engine operates at a first power output condition and an operably constant rotational speed irrespective of the rotational speed of the engine shaft when the gas turbine engine operates at a second power output condition, the second power output condition having a greater thrust output than the first power output condition;
• and
• a propulsion device of the fan section,
• wherein the propulsion device is coupled to the electrical powertrain in serial arrangement, and
• wherein the reverse Brayton cycle system further comprises a second heat exchanger, and wherein the compressor, the first heat exchanger, the turbine, and the second heat exchanger are in an operatively closed loop arrangement.

An aircraft power generation system, comprising:

• a gas turbine engine including a compressor section, a turbine section, and an engine shaft, the compressor section arranged in serial flow arrangement with the turbine section, and the engine shaft rotatable with at least a portion of the compressor section and with at least a portion of the turbine section;
• a reverse Brayton cycle system including a compressor, a first driveshaft, a turbine, and a first heat exchanger, the first driveshaft mechanically coupled with the compressor and the turbine;
• and
• a gearbox configured to receive mechanical energy from the engine shaft and transmit the mechanical energy to the reverse Brayton cycle system through the first driveshaft, wherein the compressor and the turbine of the reverse Brayton cycle system are each positioned downstream of the gearbox, the gearbox mechanically linked to the reverse Brayton cycle system, wherein a first driveshaft rotational speed is substantially equal or proportional to a rotational speed of the engine shaft when a power output condition of the gas turbine engine is less than a ground idle thrust output and is different from the rotational speed of the engine shaft regardless of changes in the rotational speed of the engine shaft when the power output condition of the gas turbine engine is greater than the ground idle thrust output;
• an electrical powertrain coupled to the gearbox through a second driveshaft separately coupled to the gearbox from the first driveshaft in a parallel arrangement;
• and
• a propulsion device,
• wherein the propulsion device is coupled to the electrical powertrain in serial arrangement, and
• wherein the reverse Brayton cycle system further comprises a second heat exchanger, and wherein the compressor, the first heat exchanger, the turbine, and the second heat exchanger are in an operatively closed loop arrangement.