A non-Wankel rotary engine having an insert in the peripheral wall of the outer body, the insert being made of a material having a greater heat resistance than that of the peripheral wall, having a subchamber defined therein and having an inner surface bordering the cavity, the subchamber communicating with the cavity through at least one opening defined in the inner surface and having a shape forming a reduced cross-section adjacent the opening, a pilot fuel injector having a tip received in the subchamber, an ignition element having a tip received in the subchamber, and a main fuel injector extending through the housing and having a tip communicating with the cavity at a location spaced apart from the insert.

In one aspect, described is a rotary engine having a purge port located rearwardly of the inlet port and forwardly of the exhaust port along a direction of the revolutions of the rotor, the purge port being in communication with the exhaust port through each of the chambers along a respective portion of each revolution, and the inlet and outlet ports being relatively located such that a volumetric compression ratio of the engine is lower than a volumetric expansion ratio of the engine.

A rotary engine including a rotor sealingly received within an internal cavity of an outer body to define a plurality of combustion chambers having a variable volume, a pilot subchamber located in a wall of the outer body, the pilot subchamber in fluid communication with the internal cavity via at least two spaced apart transfer holes defining a flow restriction between the pilot subchamber and the internal cavity, a pilot fuel injector in fluid communication with the pilot subchamber, an ignition element configured for igniting fuel in the pilot subchamber, and a main fuel injector extending through the stator body and communicating with the cavity at a location spaced apart from the pilot subchamber. A method of combusting fuel in a rotary engine is also discussed.

A method of controlling an air intake flow in a rotary engine having primary and secondary inlet ports, including positioning the secondary inlet port rearwardly of the primary inlet port and forwardly of the exhaust port along a direction of a revolution of the rotor, providing independently closable communications between an air source and the primary and secondary inlet ports, and controlling air intake flows between the air source and the primary and secondary inlet ports. Controlling air intake flows includes simultaneously allowing the air intake flow between the primary inlet port and the air source and between the secondary inlet port and the air source. Exhaust gases of the engine are purged with the air intake flow of the secondary inlet port. A rotary engine is also discussed.

A method of controlling an air intake flow in a rotary engine having primary and secondary inlet ports, including positioning the secondary inlet port rearwardly of the primary inlet port and forwardly of the exhaust port along a direction of a revolution of the rotor, providing independently closable communications between an air source and the primary and secondary inlet ports, and controlling air intake flows between the air source and the primary and secondary inlet ports. Controlling air intake flows includes simultaneously allowing the air intake flow between the primary inlet port and the air source and between the secondary inlet port and the air source. Exhaust gases of the engine are purged with the air intake flow of the secondary inlet port. A rotary engine is also discussed.

A method of controlling an air intake flow in a rotary engine having primary and secondary inlet ports, including positioning the secondary inlet port rearwardly of the primary inlet port and forwardly of the exhaust port along a direction of a revolution of the rotor, and controlling air intake flows communicating between an air source and the primary and secondary inlet ports. During engine start-up, a primary valve is closed to prevent the intake air flow between the primary inlet port and the air source and a secondary valve is opened to allow the intake air flow between the secondary inlet port and the air source. A rotary engine defining different compression ratios through actuation of a valve is also discussed.

A method of controlling an air intake flow in a rotary engine having primary and secondary inlet ports, including positioning the secondary inlet port rearwardly of the primary inlet port and forwardly of the exhaust port along a direction of a revolution of the rotor, and controlling air intake flows communicating between an air source and the primary and secondary inlet ports. During engine start-up, a primary valve is closed to prevent the intake air flow between the primary inlet port and the air source and a secondary valve is opened to allow the intake air flow between the secondary inlet port and the air source. A rotary engine defining different compression ratios through actuation of a valve is also discussed.

A compound engine system includes a rotary engine with rotating chambers, a compressor section in successive communication with the rotating chambers, and a turbine section in successive communication with the rotating chambers. The turbine section has an output shaft. The output shaft and the engine shaft are drivingly engaged to each other and wherein the turbine section has a power output corresponding to from 20% to 35% of a total power output of the compound engine system. A method of compounding power in a compound engine system is also discussed.

Scroll expander including a bypass passage and a bypass valve configured to open and close the bypass passage without significantly increasing the length in the shaft direction of the scroll expander. Scroll expander 23 includes suction port 513 which allows a high-pressure flow of a working fluid to enter and guides the entering flow of the working fluid into an expansion chamber. Discharge port 523 allows the working fluid expanded to a lower pressure in the expansion chamber to flow out. Bypass passage 27 communicates suction port 513 with the discharge port 523 while bypassing the expansion chamber. Bypass valve 28 is configured to open and close bypass passage 27. Suction port 513, bypass passage 27 and a bypass valve attaching portion 514 for attaching the bypass valve 28 are formed in a base plate of the fixed scroll 51.

A method of controlling an air intake flow in a rotary engine having primary and secondary inlet ports, including positioning the secondary inlet port rearwardly of the primary inlet port and forwardly of the exhaust port along a direction of a revolution of the rotor, and controlling air intake flows communicating between an air source and the primary and secondary inlet ports. During engine start-up, a primary valve is closed to prevent the intake air flow between the primary inlet port and the air source and a secondary valve is opened to allow the intake air flow between the secondary inlet port and the air source. A rotary engine defining different compression ratios through actuation of a valve is also discussed.