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.

Abstract: A method of operating an engine assembly receiving fuel, including admitting atmospheric air at a temperature T1 through an inlet of a compressor having a pressure ratio of PRGT, compressing the air in the compressor, cooling the compressed air from the compressor through an intercooler to cool the air from a temperature TBIC to a temperature TAIC, delivering the cooled compressed air from the intercooler to an inlet of an intermittent internal combustion engine having an effective volumetric compression ratio rVC, and further compressing the air in the intermittent internal combustion engine before igniting the fuel, where ( PR GT ) a ? ( r VC ) b ? ( T AIC T BIC ) ? ( T 1 T A ) < 1. An engine assembly is also discussed.

Abstract: A cooling system for an internal combustion engine comprises a fluid circuit having an intercooler, a main cooler and a precooler. The intercooler is configured for receiving coolant and configured for heat exchange relation between the coolant and engine compressed air. The main cooler is configured for receiving the coolant from the intercooler and the internal combustion engine and configured for selectively delivering a first portion of the coolant from the main cooler to the precooler. The precooler is configured to deliver a flow of the coolant to the intercooler. The main cooler and the precooler are configured for cooling the coolant by heat exchange with at least one cooling flow.

Abstract: Systems and methods for detecting at least one non-functional combustion chamber of an engine comprising a plurality of combustion chambers are described herein. In response to detecting a partial output power loss of the engine, one of the plurality of combustion chambers is assessed by monitoring an engine parameter indicative of an output power of the engine, determining whether a change in the engine parameter has occurred, when the change has occurred, determining that the combustion chamber is functional, and when no change has occurred, determining that the combustion chamber is non-functional and discontinuing fuel injection to the non-functional combustion chamber.

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: 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.

Abstract: A method of operating an engine assembly receiving fuel, including admitting atmospheric air at a temperature T1 through an inlet of a compressor having a pressure ratio of PRGT, compressing the air in the compressor, cooling the compressed air from the compressor through an intercooler to cool the air from a temperature TBIC to a temperature TAIC, delivering the cooled compressed air from the intercooler to an inlet of an intermittent internal combustion engine having an effective volumetric compression ratio rVC, and further compressing the air in the intermittent internal combustion engine before igniting the fuel, where ( PR GT ) a ? ( r VC ) b ? ( T AIC T BIC ) ? ( T 1 T A ) < 1. An engine assembly is also discussed.

Abstract: 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.

Abstract: A method of operating an engine assembly receiving fuel, including admitting atmospheric air at a temperature T1 through an inlet of a compressor having a pressure ratio of PRGT, compressing the air in the compressor, cooling the compressed air from the compressor through an intercooler to cool the air from a temperature TBIC to a temperature TAIC, delivering the cooled compressed air from the intercooler to an inlet of an intermittent internal combustion engine having an effective volumetric compression ratio rVC, and further compressing the air in the intermittent internal combustion engine before igniting the fuel, where ( PR GT ) a ? ( r VC ) b ? ( T AIC T BIC ) ? ( T 1 T A ) < 1. An engine assembly is also discussed.

Abstract: A method of operating an internal combustion engine having pilot subchambers communicating with main combustion chambers, the internal combustion engine configured in use to deliver a main fuel injection of a maximum quantity of fuel to the main combustion chambers when the internal combustion engine is operated at maximum load. The method includes delivering a pilot fuel injection of at most 10% of the maximum quantity to the pilot subchambers, igniting the pilot fuel injection within the pilot subchambers, directing the ignited fuel from the pilot subchambers to the main combustion chambers, and delivering a main fuel injection of a main quantity of fuel to at least one of the main combustion chambers receiving the ignited fuel, with the main quantity being at most 10% of the maximum quantity.

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.

Abstract: An internal combustion engine including an igniter disposed at least partially within an aperture defined in a housing of the engine, the igniter having a body including a tip supporting portion and having a tip extending from the tip supporting portion. A cooling sleeve is disposed around the tip supporting portion, and the cooling sleeve defines a path of heat transfer between the tip supporting portion and the housing. The engine may be a rotary engine. A method for cooling an igniter of an internal combustion engine is also discussed.

Abstract: Systems and methods for detecting at least one non-functional combustion chamber of an engine comprising a plurality of combustion chambers are described herein. In response to detecting a partial output power loss of the engine, one of the plurality of combustion chambers is assessed by monitoring an engine parameter indicative of an output power of the engine, determining whether a change in the engine parameter has occurred, when the change has occurred, determining that the combustion chamber is functional, and when no change has occurred, determining that the combustion chamber is non-functional and discontinuing fuel injection to the non-functional combustion chamber.

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: A method of operating an engine assembly receiving fuel, including admitting atmospheric air at a temperature T1 through an inlet of a compressor having a pressure ratio of PRGT, compressing the air in the compressor, cooling the compressed air from the compressor through an intercooler to cool the air from a temperature TBIC to a temperature TAIC, delivering the cooled compressed air from the intercooler to an inlet of an intermittent internal combustion engine having an effective volumetric compression ratio rVC, and further compressing the air in the intermittent internal combustion engine before igniting the fuel, where (PRGT)a (rVC)b (TAIC/TBIC)(T1/TA)<1. An engine assembly is also discussed.

Abstract: A cooling system for an internal combustion engine comprises a fluid circuit having an intercooler, a main cooler and a precooler. The intercooler is configured for receiving coolant and configured for heat exchange relation between the coolant and engine compressed air. The main cooler is configured for receiving the coolant from the intercooler and the internal combustion engine and configured for selectively delivering a first portion of the coolant from the main cooler to the precooler. The precooler is configured to deliver a flow of the coolant to the intercooler. The main cooler and the precooler are configured for cooling the coolant by heat exchange with at least one cooling flow.

Abstract: A method of operating an internal combustion engine having pilot subchambers communicating with main combustion chambers, the internal combustion engine configured in use to deliver a main fuel injection of a maximum quantity of fuel to the main combustion chambers when the internal combustion engine is operated at maximum load. The method includes delivering a pilot fuel injection of at most 10% of the maximum quantity to the pilot subchambers, igniting the pilot fuel injection within the pilot subchambers, directing the ignited fuel from the pilot subchambers to the main combustion chambers, and delivering a main fuel injection of a main quantity of fuel to at least one of the main combustion chambers receiving the ignited fuel, with the main quantity being at most 10% of the maximum quantity.

Abstract: 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.

Abstract: An internal combustion engine including an igniter disposed at least partially within an aperture defined in a housing of the engine, the igniter having a body including a tip supporting portion and having a tip extending from the tip supporting portion. A cooling sleeve is disposed around the tip supporting portion, and the cooling sleeve defines a path of heat transfer between the tip supporting portion and the housing. The engine may be a rotary engine. A method for cooling an igniter of an internal combustion engine is also discussed.

Abstract: A method of operating an internal combustion engine having pilot subchambers communicating with main combustion chambers, the internal combustion engine configured in use to deliver a main fuel injection of a maximum quantity of fuel to the main combustion chambers when the internal combustion engine is operated at maximum load. The method includes delivering a pilot fuel injection of at most 10% of the maximum quantity to the pilot subchambers, igniting the pilot fuel injection within the pilot subchambers, directing the ignited fuel from the pilot subchambers to the main combustion chambers, and delivering a main fuel injection of a main quantity of fuel to at least one of the main combustion chambers receiving the ignited fuel, with the main quantity being at most 10% of the maximum quantity.