Abstract: A method of operating a rotary engine including a rotor engaged to a shaft and rotationally received in a housing to define a plurality of working chambers of variable volume, including delivering a pilot quantity of fuel into a pilot cavity in successive communication with the working chambers, igniting the pilot quantity of fuel within the pilot cavity, and delivering a main quantity of fuel into the working chambers downstream of the successive communication of the pilot cavity with the working chambers, where at least one of the pilot quantity and the main quantity is varied between successive rotations of the shaft.

Abstract: An engine assembly including an engine core including at least one internal combustion engine each including a rotor sealingly and rotationally received within a respective internal cavity to provide rotating chambers of variable volume in the respective internal cavity, a compressor having an outlet in fluid communication with an inlet of the engine core, a first intake conduit in fluid communication with an inlet of the compressor and with a first source of air, a second intake conduit in fluid communication with the inlet of the compressor and with a second source of air warmer than the first source of air, and a selector valve configurable to selectively open and close at least the fluid communication between the inlet of the compressor and the first intake conduit. A method of supplying air to a compressor is also discussed.

Abstract: A method of operating a rotary engine including a rotor engaged to a shaft and rotationally received in a housing to define a plurality of working chambers of variable volume, including delivering a pilot quantity of fuel into a pilot cavity in successive communication with the working chambers, igniting the pilot quantity of fuel within the pilot cavity, and delivering a main quantity of fuel into the working chambers downstream of the successive communication of the pilot cavity with the working chambers, where at least one of the pilot quantity and the main quantity is varied between successive rotations of the shaft.

Abstract: A rotary engine including at least two pilot subchambers each in parallel fluid communication with the internal cavity, so that each pilot subchamber is in fluid communication with the combustion chambers as the rotor rotates. Each of the at least two pilot subchambers in fluid communication with a corresponding pilot fuel injector. At least one ignition source is configured for igniting fuel in the pilot subchambers. A compound engine assembly and a method of combusting fuel in a rotary engine are also discussed.

Abstract: An auxiliary power unit for an aircraft, having a compressor, an intercooler including first conduit(s) having an inlet in fluid communication with the compressor outlet and second conduit(s) configured for circulation of a coolant therethrough, an engine core having an inlet in fluid communication with an outlet of the first conduit(s), and a bleed conduit in fluid communication with the outlet of the first conduit(s) through a bleed air valve. The auxiliary power unit may include a generator in driving engagement with the shaft of the engine core to provide electrical power for the aircraft. A method of providing compressed air and electrical power to an aircraft is also discussed.

Abstract: There is disclosed a method of operating an engine assembly, including: driving a load with an internal combustion engine and an output of a turbine section, the turbine section driven by combustion gases from an exhaust the internal combustion engine; and injecting fuel upstream of the turbine section and downstream of the exhaust of the internal combustion engine. An engine assembly having a secondary injector for injecting fuel upstream of the turbine section and downstream of the combustion engine is also disclosed.

Abstract: A hybrid propulsion system includes a heat engine configured to drive a heat engine shaft. An electric motor is configured to drive an electric motor shaft. A transmission system includes at least one gearbox. The transmission system is configured to receive rotational input power from each of the heat engine shaft and the electric motor shaft and to convert the rotation input power to output power.

Abstract: A method of operating a hybrid electric power plant in cold climates comprises absorbing heat generated by an internal combustion engine, and using at least part of the heat absorbed from the internal combustion engine to warm a battery pack operatively connected to an electric motor.

Abstract: There is disclosed an engine assembly for an aircraft, including: a combustion engine including a coolant circuit in heat exchange relationship with a heat sink, the heat sink including a heat exchanger and at least one component, the at least one component having a main function that differs from thermal exchange. A method of operating the system is also disclosed.

Abstract: An auxiliary power unit for an aircraft includes a rotary intermittent internal combustion engine, a turbine having an inlet in fluid communication with an outlet of the engine, the turbine compounded with the engine, a compressor having an inlet in fluid communication with an environment of the aircraft and an outlet in fluid communication with the aircraft, the compressor rotatable independently of the turbine, an electric motor drivingly engaged to the compressor, and a transfer generator drivingly engaged to the engine, the transfer generator and the electric motor being electrically connected to allow power transfer therebetween. The compressor or an additional compressor may be in fluid communication with the inlet of the engine. A method of operating an auxiliary power unit of an aircraft is also discussed.

Abstract: An auxiliary power unit for an aircraft, having a compressor, an intercooler including first conduit(s) having an inlet in fluid communication with the compressor outlet and second conduit(s) configured for circulation of a coolant therethrough, an engine core having an inlet in fluid communication with an outlet of the first conduit(s), and a bleed conduit in fluid communication with the outlet of the first conduit(s) through a bleed air valve. The auxiliary power unit may include a generator in driving engagement with the shaft of the engine core to provide electrical power for the aircraft. A method of providing compressed air and electrical power to an aircraft is also discussed.

Abstract: A turbofan engine assembly including a compressor, an intermittent internal combustion engine having an inlet in fluid communication with an outlet of the compressor through at least one first passage of an intercooler, a turbine having an inlet in fluid communication with an outlet of the intermittent internal combustion engine, the turbine compounded with the intermittent internal combustion engine, a bypass duct surrounding the intermittent internal combustion engine, compressor and turbine, and a fan configured to propel air through the bypass duct and through an inlet of the compressor, wherein the intercooler is located in the bypass duct, the intercooler having at least one second passage in heat exchange relationship with the at least one first passage, the at least one second passage in fluid communication with the bypass duct.

Abstract: An auxiliary power unit for an aircraft, having an engine core, a compressor having an outlet in fluid communication with the engine core inlet, a turbine section in fluid communication with the engine core outlet, and an excess air duct having a first end in fluid communication with the compressor outlet and a second end in fluid communication with a turbine inlet of the turbine section. The excess air duct defines a flow path between the compressor outlet and the turbine section separate from the engine core. The auxiliary power unit may include a generator in driving engagement with the engine core to provide electrical power for the aircraft. A method of providing compressed air and electrical power to an aircraft is also discussed.

Abstract: A compound engine assembly for use as an auxiliary power unit for an aircraft and including an engine core with internal combustion engine(s), a compressor having an outlet in fluid communication with an engine core inlet, a bleed conduit in fluid communication with the compressor outlet through a bleed air valve, and a turbine section having an inlet in fluid communication with the engine core outlet and configured to compound power with the engine core. The turbine section may include a first stage turbine having an inlet in fluid communication with the engine core outlet and a second stage turbine having an inlet in fluid communication the first stage turbine outlet. A method of providing compressed air and electrical power to an aircraft is also discussed.

Abstract: A compound engine assembly with an inlet duct, a compressor, an engine core including at least one internal combustion engine, and a turbine section including a turbine shaft configured to compound power with the engine shaft. The turbine section may include a first stage turbine and a second stage turbine. The turbine shaft and the engine shaft are parallel to each other. The turbine shaft, the engine shaft and at least part of the inlet duct are all radially offset from one another. A method of driving a rotatable load of an aircraft is also discussed.

Abstract: An engine assembly includes an engine compartment containing an internal combustion engine and a cooler compartment adjacent the engine compartment containing a heat exchanger. The engine and cooler compartments have an opening defined therebetween. A forced air system is operable to drive an airflow. A method for cooling the engine and its compartment is disclosed.

Abstract: A method of cooling an auxiliary power unit (APU) of an aircraft having prime mover engines fed with aircraft fuel, comprises: using the aircraft fuel as a heat sink to absorb the heat generated by the APU.

Abstract: A method of operating a hybrid electric power plant in cold climates comprises absorbing heat generated by an internal combustion engine, and using at least part of the heat absorbed from the internal combustion engine to warm a battery pack operatively connected to an electric motor.

Abstract: A turbofan engine assembly including a compressor, an intermittent internal combustion engine having an inlet in fluid communication with an outlet of the compressor through at least one first passage of an intercooler, a turbine having an inlet in fluid communication with an outlet of the intermittent internal combustion engine, the turbine compounded with the intermittent internal combustion engine, a bypass duct surrounding the intermittent internal combustion engine, compressor and turbine, and a fan configured to propel air through the bypass duct and through an inlet of the compressor, wherein the intercooler is located in the bypass duct, the intercooler having at least one second passage in heat exchange relationship with the at least one first passage, the at least one second passage in fluid communication with the bypass duct.

Abstract: A rotary internal combustion engine including a rotor assembly where at least a first and a second of the combustion chambers have unequal theoretical volumetric ratios. Also, a rotary internal combustion engine including first and second rotor assemblies where at least one of the combustion chambers of the first rotor assembly and at least one of the combustion chambers of the second rotor assembly have unequal effective volumetric compression ratios and/or unequal effective volumetric expansion ratios.