Abstract: A compound engine assembly with an engine core including at least one internal combustion engine, a turbine section, and a compressor having an outlet in fluid communication with an inlet of the engine core. A casing is connected to the turbine section, the compressor and the engine core. A mount cage is connected to mounts attached to the casing between the compressor and a hot zone including the turbine section and the engine core. The mount cage includes a plurality of struts all extending from the mounts away from the turbine section and engine core. The casing may be a gearbox module casing through which the turbine shaft in engaged with the engine shaft. The mount cage may be completely contained within an axial space with the turbine section and engine core being located outside of the axial space.

Abstract: A compound engine assembly with an engine core including at least one internal combustion engine, a turbine section, and a compressor having an outlet in fluid communication with an inlet of the engine core. A casing is connected to the turbine section, compressor and engine core. A mount cage is connected to mounts attached to the casing between the compressor and a hot zone including the turbine section and exhaust pipe(s). The struts are separated from the hot zone by at least one firewall. The mount cage may include a plurality of struts all extending from the mounts away from the turbine section and engine core. The casing may be a gearbox module casing through which the turbine shaft in engaged with the engine shaft. The mount cage may be completely contained within an axial space with the turbine section and exhaust pipe(s) being located outside of the axial space.

Abstract: A compound engine assembly with an inlet duct having an inlet surrounded by an inlet lip including at least one conduit extending therethrough, a compressor, an engine core including at least one internal combustion engine, a turbine section having a turbine shaft in driving engagement with the engine shaft, and an exhaust conduit providing a fluid communication between the outlet of the turbine section and the conduit(s) of the inlet lip. An exhaust duct and ant exhaust conduit providing a fluid communication between the outlet of the turbine section and the exhaust duct may also be provided. The internal combustion engine(s) may be rotary engine(s). A method of driving a rotatable load of an aircraft is also discussed.

Abstract: An engine assembly including an engine core with at least one internal combustion engine, a first casing, a turbine module including a second casing located outside of the first casing, and a compressor module including a third casing located outside of the first and second casings. The turbine shaft extends into the first casing, is rotationally supported by a bearings all contained within the first casing, and is free of rotational support within the second casing. The first casing may be a gearbox module casing through which the turbine shaft is in driving engagement with the engine shaft. A method of driving a rotatable load of an aircraft, and an engine assembly with a rotary engine core, a gearbox module with a first casing, and a second module including a second casing located outside of the first casing and detachably connected to the first casing are also discussed.

Abstract: A compound engine assembly with an engine core including at least one internal combustion engine, a turbine section including a turbine shaft in driving engagement with the engine shaft, and a compressor, and a firewall. The compressor is located on one side of the firewall, and the turbine section and the engine core are located on the other side. The assembly may include a gearbox module with the turbine section and the engine core located on a same side of the gearbox module casing and the compressor located on the opposite side of the gearbox module casing, and with the firewall extending from the gearbox module casing. One or more rotatable accessory may be located on a same side of the firewall as the compressor. A method of reducing fire hazard in a compound engine assembly is also discussed.

Abstract: A gas turbine engine including at least one high pressure turbine rotor and at least one high pressure compressor rotor drivingly engaged to a rotatable high pressure spool, a low pressure spool rotatable independently of the high pressure spool, at least one low pressure turbine rotor drivingly engaged to the low pressure spool, and a rotatable load drivingly engaged to the low pressure spool. A fixed rotational speed ratio is defined between rotational speeds of the at high pressure turbine and compressor rotors. A fixed rotational speed ratio is defined between rotational speeds of the low pressure turbine rotor(s) and of the low pressure spool. A low pressure compressor rotor is in driving engagement with the low pressure spool through a variable transmission which defines a variable rotational speed ratio between the rotational speeds of the low pressure spool and of the low pressure compressor rotor.

Abstract: A compound engine assembly with an engine core including at least one internal combustion engine, a turbine section including a turbine shaft in driving engagement with the engine shaft, and a compressor, and a firewall. The compressor is located on one side of the firewall, and the turbine section and the engine core are located on the other side. The assembly may include a gearbox module with the turbine section and the engine core located on a same side of the gearbox module casing and the compressor located on the opposite side of the gearbox module casing, and with the firewall extending from the gearbox module casing. One or more rotatable accessory may be located on a same side of the firewall as the compressor. A method of reducing fire hazard in a compound engine assembly is also discussed.

Abstract: An engine assembly including an engine core with at least one internal combustion engine, a first casing, a turbine module including a second casing located outside of the first casing, and a compressor module including a third casing located outside of the first and second casings. The turbine shaft extends into the first casing, is rotationally supported by a bearings all contained within the first casing, and is free of rotational support within the second casing. The first casing may be a gearbox module casing through which the turbine shaft is in driving engagement with the engine shaft. A method of driving a rotatable load of an aircraft, and an engine assembly with a rotary engine core, a gearbox module with a first casing, and a second module including a second casing located outside of the first casing and detachably connected to the first casing are also discussed.

Abstract: A compound engine assembly with an engine core including at least one internal combustion engine, a turbine section, and a compressor having an outlet in fluid communication with an inlet of the engine core. A casing is connected to the turbine section, compressor and engine core. A mount cage is connected to mounts attached to the casing between the compressor and a hot zone including the turbine section and exhaust pipe(s). The struts are separated from the hot zone by at least one firewall. The mount cage may include a plurality of struts all extending from the mounts away from the turbine section and engine core. The casing may be a gearbox module casing through which the turbine shaft in engaged with the engine shaft. The mount cage may be completely contained within an axial space with the turbine section and exhaust pipe(s) being located outside of the axial space.

Abstract: A compound engine assembly with an inlet duct having an inlet surrounded by an inlet lip including at least one conduit extending therethrough, a compressor, an engine core including at least one internal combustion engine, a turbine section having a turbine shaft in driving engagement with the engine shaft, and an exhaust conduit providing a fluid communication between the outlet of the turbine section and the conduit(s) of the inlet lip. An exhaust duct and ant exhaust conduit providing a fluid communication between the outlet of the turbine section and the exhaust duct may also be provided. The internal combustion engine(s) may be rotary engine(s). A method of driving a rotatable load of an aircraft is also discussed.

Abstract: A compound engine assembly with an engine core including at least one internal combustion engine, a turbine section, and a compressor having an outlet in fluid communication with an inlet of the engine core. A casing is connected to the turbine section, the compressor and the engine core. A mount cage is connected to mounts attached to the casing between the compressor and a hot zone including the turbine section and the engine core. The mount cage includes a plurality of struts all extending from the mounts away from the turbine section and engine core. The casing may be a gearbox module casing through which the turbine shaft in engaged with the engine shaft. The mount cage may be completely contained within an axial space with the turbine section and engine core being located outside of the axial space.

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: A method of adjusting a rotational speed of the low pressure compressor rotor(s) of a gas turbine engine, including rotating the high pressure compressor rotor(s) with the high pressure turbine rotor(s) through the high pressure spool, rotating the low pressure turbine rotor(s) with a flow of exhaust gases from the high pressure turbine, rotating the low pressure spool with the low pressure turbine rotor(s), rotating a load of the engine with the low pressure spool, driving a rotation of the low pressure compressor rotor(s) with the low pressure spool through a variable transmission defining a variable transmission ratio between rotational speeds of the compressor rotor(s) and the low pressure spool, and adjusting the transmission ratio to obtain a desired rotational speed for the low pressure compressor rotor(s). A method of adjusting rotational speeds of a gas turbine engine and a gas turbine engine are also described.