Thermal management system for an aircraft including an electric propulsion engine
An aircraft includes an aircraft heat source; a propulsion system including an electric propulsion engine, the electric propulsion engine including an electric motor and a fan rotatable by the electric motor, the electric propulsion engine further defining a fan air flowpath; a thermal management system including a heat source exchanger in thermal communication with the aircraft heat source, a heat sink exchanger in thermal communication with the fan air flowpath of the electric propulsion engine, and a thermal distribution bus extending from the heat source exchanger to the heat sink exchanger; and a control system operably connected to the thermal management system for selectively thermally coupling the heat sink exchanger with the heat source exchanger.
1 . A method for operating an aircraft comprising:
receiving data indicative of an operating condition of an electric propulsion engine of a propulsion system of the aircraft, the electric propulsion engine comprising an electric motor for driving a fan, a stage of inlet guide vanes upstream of the fan, a stage of outlet guide vanes downstream of the fan, an engine heat source exchanger for receiving heat from the electric motor, a first heat sink exchanger in thermal communication with the engine heat source exchanger and coupled to the stage of inlet guide vanes, and a second heat sink exchanger in thermal communication with a heat source exchanger of the aircraft and coupled to the stage of inlet guide vanes;
rejecting heat from the engine heat source exchanger to the first heat sink exchanger in thermal communication with a fan air flowpath of the electric propulsion engine;
receiving data indicative of a desired amount of heat exchange from the heat source exchanger in thermal communication with an aircraft heat source to the second heat sink exchanger in thermal communication with the fan air flowpath of the electric propulsion engine; and
controlling an actual amount of heat exchange from the heat source exchanger to the second heat sink exchanger by controlling a speed of the fan of the electric propulsion engine based on the received data indicative of the operating condition of the electric propulsion engine and the received data indicative of the desired amount of heat exchange.
2 . The method of claim 1 , wherein the operating condition of the electric propulsion engine is the speed of the fan of the electric propulsion engine.
3 . The method of claim 1 , wherein:
controlling the speed of the fan of the electric propulsion engine comprises reducing the speed of the fan of the electric propulsion engine; and
reducing the speed of the fan of the electric propulsion engine comprises reducing the speed of the fan during flight operations of the aircraft to less than twenty (20) percent of a maximum rated speed.
4 . The method of claim 1 , wherein controlling the actual amount of heat exchange from the heat source exchanger to the second heat sink exchanger comprises metering an airflow through the fan air flowpath to facilitate provision of the desired amount of heat exchange from the heat source exchanger to the second heat sink exchanger.
5 . The method of claim 1 , wherein controlling the actual amount of heat exchange from the heat source exchanger to the second heat sink exchanger comprises controlling a flow regulation device in flow communication with a thermal bus extending between the heat source exchanger and the second heat sink exchanger.
6 . The method of claim 5 , wherein the flow regulation device is a variable throughput valve positioned in flow communication with a thermal distribution bus, a thermal fluid pump positioned in flow communication with the thermal distribution bus, or both.
7 . The method of claim 1 , wherein the aircraft heat source is an avionics system heat source, a cockpit heat source, an aircraft environmental control system heat source, a combustion engine heat source, a non-biological heat source, or a hydraulic load heat source.
8 . The method of claim 1 , further comprising:
a pair of wings, wherein heat source exchanger is aligned with the pair of wings along a longitudinal direction of the aircraft or positioned forward of the pair of wings along the longitudinal direction of the aircraft, and wherein the first heat sink exchanger and the second heat sink exchanger is positioned aft of the pair of wings along the longitudinal direction of the aircraft.