A compound engine assembly including an air conduit having an inlet in fluid communication with ambient air around the compound engine assembly, a compressor having an inlet in fluid communication with the air conduit, an engine core including at least one rotary internal combustion engine and having an inlet in fluid communication with an outlet of the compressor, a turbine section having an inlet in fluid communication with an outlet of the engine core and configured to compound power with the engine core; and at least one heat exchanger in fluid communication with the air conduit, each heat exchanger configured to circulate a fluid of the engine assembly in heat exchange relationship with an airflow from the air conduit circulating therethrough. A method of supplying air to a compound engine assembly is also discussed.

Sealing in rotary positive displacement machines based on trochoidal geometry that comprise a helical rotor that undergoes planetary motion within a helical stator is described. Seals can be mounted on the rotor, the stator, or both. The rotor can have a hypotrochoidal cross-section, with the corresponding stator cavity profile being the outer envelope of the rotor as it undergoes planetary motion, or the stator cavity can have an epitrochoidal cross-section with the corresponding rotor profile being the inner envelope of the trochoid as it undergoes planetary motion. In some embodiments, the geometry is offset in a manner that provides advantages with respect to sealing in the rotary machine. In multi-stage embodiments, the rotor-stator geometry remains substantially constant or varies along the axis of the rotary machine.

Sealing in rotary positive displacement machines based on trochoidal geometry that comprise a helical rotor that undergoes planetary motion within a helical stator is described. Seals can be mounted on the rotor, the stator, or both. The rotor can have a hypotrochoidal cross-section, with the corresponding stator cavity profile being the outer envelope of the rotor as it undergoes planetary motion, or the stator cavity can have an epitrochoidal cross-section with the corresponding rotor profile being the inner envelope of the trochoid as it undergoes planetary motion. In some embodiments, the geometry is offset in a manner that provides advantages with respect to sealing in the rotary machine. In multi-stage embodiments, the rotor-stator geometry remains substantially constant or varies along the axis of the rotary machine.

A topological rotary engine includes a first transmission mechanism, a second transmission mechanism, a valve mechanism, a rotor, and a cylinder. The rotor is arranged in an inner chamber of the cylinder. A cross section of the rotor is a curved-side topological polygon having n sides. A cross section of the inner chamber of cylinder is a curved-side topological polygon having n+1 sides, and n is an even number greater than or equal to 4. An outer topological curved surface of the rotor is meshed with an inner topological curved surface of the cylinder. The rotor reversely revolves around an axis of the cylinder with an eccentricity as a radius while rotating, and divides the cylinder into n+1 independent chambers. The cylinder is provided with n+1 fuel injection nozzles and n+1 spark plugs, which cooperate with the rotor and the valve mechanism.

A topological rotary engine includes a first transmission mechanism, a second transmission mechanism, a valve mechanism, a rotor, and a cylinder. The rotor is arranged in an inner chamber of the cylinder. A cross section of the rotor is a curved-side topological polygon having n sides. A cross section of the inner chamber of cylinder is a curved-side topological polygon having n+1 sides, and n is an even number greater than or equal to 4. An outer topological curved surface of the rotor is meshed with an inner topological curved surface of the cylinder. The rotor reversely revolves around an axis of the cylinder with an eccentricity as a radius while rotating, and divides the cylinder into n+1 independent chambers. The cylinder is provided with n+1 fuel injection nozzles and n+1 spark plugs, which cooperate with the rotor and the valve mechanism.

An engine assembly for an aircraft, including an internal combustion engine having a liquid coolant system in fluid communication with a heat exchanger, an exhaust duct in fluid communication with air passages of the heat exchanger, a fan in fluid communication with the exhaust duct for driving a cooling air flow through the air passages of the heat exchanger and into the exhaust duct, and an intermediate duct in fluid communication with an exhaust of the engine and having an outlet positioned within the exhaust duct downstream of the fan and upstream of the outlet of the exhaust duct. The outlet of the intermediate duct is spaced inwardly from a peripheral wall of the exhaust duct. The engine assembly may be configured as an auxiliary power unit. A method of discharging air and exhaust gases in an auxiliary power unit having an internal combustion engine is also discussed.

An engine assembly having an internal combustion engine, a turbine module including a turbine casing, a support casing rigidly connecting the turbine casing to a remainder of the assembly, and an inlet scroll connected to the turbine casing without any direct rigid connection to the support casing. The inlet scroll includes an inlet pipe for each engine exhaust port. An exhaust pipe is provided for each exhaust port, connected to and providing fluid communication between the respective exhaust port and inlet pipe. The exhaust pipe is movable relative to at least one of the exhaust port and the inlet pipe at a corresponding connection therewith. One of the exhaust and inlet pipes floatingly extends through an opening defined in the support casing. The assembly may be a compound engine assembly.

An internal combustion engine including a pilot subchamber, a pilot fuel injector having a tip in communication with the pilot subchamber, an ignition element positioned to ignite fuel within the pilot subchamber, and a main fuel injector spaced apart from the pilot fuel injector. The engine includes a common rail in fluid communication with the main fuel injector and with the pilot fuel injector. The internal combustion engine may be a reciprocating engine. A method of combusting fuel in an internal combustion engine is also provided.

An internal combustion engine including a pilot subchamber, a pilot fuel injector having a tip in communication with the pilot subchamber, an ignition element positioned to ignite fuel within the pilot subchamber, and a main fuel injector spaced apart from the pilot fuel injector. The engine includes a common rail in fluid communication with the main fuel injector and with the pilot fuel injector. The internal combustion engine may be a reciprocating engine. A method of combusting fuel in an internal combustion engine is also provided.

A light-weight, high-strength compressor component having at least one fluid delivery feature that is formed via additive manufacturing is provided. The component may have at least one interior region comprising a lattice structure that comprises a plurality of repeating cells. A solid surface is disposed over the lattice structure. The interior region comprising the lattice structure has at least one fluid delivery feature for permitting fluid flow through the body portion of the light-weight, high-strength compressor component. The fluid delivery feature may be a flow channel, a fluid delivery port, a porous fluid delivery feature, or the like that serves to transfer fluids through the component, such as refrigerant and/or lubricant oils. Methods of making such compressor components via additive manufacturing processes are also provided.