A compound engine system including a Wankel engine having a recess defined in the peripheral wall of the rotor in each of the three rotating chambers, the recess having a volume of more than 5% of the displacement volume of the chambers. The expansion in the turbine section compensates for the relatively low expansion ratio of the rotary engine.

An arc turbine system includes an elliptical housing, a rotor having two sliding channels positioned centrically to the housing, and two sliding arcs disposed within the rotor sliding channels and slide therein. The sliding arcs are engaging the housing simultaneously at both ends in a near friction-free environment supported by repulsion force of like-pole magnets. Four chambers disposed within two static chambers between the rotor and the long-axis of said housing, the two static chambers further include proper inlet and outlet ports configured to allow fluid and gas flow into and flow out of the static chambers. The system configured in two distinct settings for two distinct uses. 1) To generate dense rotating energy with optimum efficiency, and high power-to-weight ratio by burning fuel and 2) to pump, compress, vacuum, convey, pressurize, turbocharge, allow precision and micro-movement of gas and liquid, conversion of pressurized gas and liquid to rotating energy, all with optimum efficiency, near-zero vibration, near-zero friction, capability of handling all viscous fluids and 100% increased flow rate using dual inlet and dual outlet ports.

An arc turbine system includes an elliptical housing, a rotor having two sliding channels positioned centrically to the housing, and two sliding arcs disposed within the rotor sliding channels and slide therein. The sliding arcs are engaging the housing simultaneously at both ends in a near friction-free environment supported by repulsion force of like-pole magnets. Four chambers disposed within two static chambers between the rotor and the long-axis of said housing, the two static chambers further include proper inlet and outlet ports configured to allow fluid and gas flow into and flow out of the static chambers. The system configured in two distinct settings for two distinct uses. 1) To generate dense rotating energy with optimum efficiency, and high power-to-weight ratio by burning fuel and 2) to pump, compress, vacuum, convey, pressurize, turbocharge, allow precision and micro-movement of gas and liquid, conversion of pressurized gas and liquid to rotating energy, all with optimum efficiency, near-zero vibration, near-zero friction, capability of handling all viscous fluids and 100% increased flow rate using dual inlet and dual outlet ports.

Rotary vane internal combustion engine comprises of two rotors, nested in each other, placed in a cylindrical housing, wherein each rotor has at least two radial vanes rigidly attached to the rotor that form chambers for intake, compression, combustion, and exhaust. Each rotor, alternately engages with a shaft by overrunning one-way clutches and held from turning back, through the cushioning mechanisms, mounted on flywheels, which are rigidly attached on the shaft, wherein the assembled rotors from the outside are rigidly closed by flanges on each of which is mounted at least one blade, which are placed into formed cavity between rotors and caps of the housing thereby forming two cooling chambers through which coolant circulates around rotors through openings in the housing and through longitudinal grooves in the shaft. On the vanes mounted cylindrical and conical seals that exclude the need for lubrication.

Rotary vane internal combustion engine comprises of two rotors, nested in each other, placed in a cylindrical housing, wherein each rotor has at least two radial vanes rigidly attached to the rotor that form chambers for intake, compression, combustion, and exhaust. Each rotor, alternately engages with a shaft by overrunning one-way clutches and held from turning back, through the cushioning mechanisms, mounted on flywheels, which are rigidly attached on the shaft, wherein the assembled rotors from the outside are rigidly closed by flanges on each of which is mounted at least one blade, which are placed into formed cavity between rotors and caps of the housing thereby forming two cooling chambers through which coolant circulates around rotors through openings in the housing and through longitudinal grooves in the shaft. On the vanes mounted cylindrical and conical seals that exclude the need for lubrication.

A method of cooling an aircraft power plant having a combustion engine is disclosed. The method comprises in a first operating mode, inducing a cooling air flow through a heat exchanger in an air conduit via a flow inducing device fluidly connected to the air conduit, the heat exchanger connected in heat exchange relationship with the power plant of the aircraft. The method comprises, in a second operating mode, bypassing the cooling air flow from the flow inducing device via a selectively closable air outlet of the air conduit downstream of the heat exchanger. A cooling system for an aircraft power plant is also disclosed.

A method of cooling an aircraft power plant having a combustion engine is disclosed. The method comprises in a first operating mode, inducing a cooling air flow through a heat exchanger in an air conduit via a flow inducing device fluidly connected to the air conduit, the heat exchanger connected in heat exchange relationship with the power plant of the aircraft. The method comprises, in a second operating mode, bypassing the cooling air flow from the flow inducing device via a selectively closable air outlet of the air conduit downstream of the heat exchanger. A cooling system for an aircraft power plant is also disclosed.

A hub assembly for use in a compressed air driven inverter generator is provided. The hub assembly comprises: a hub comprising a plate with a cylindrical protrusion centered on a bottom face and a bore hole through the center of the plate and protrusion, the protrusion sized to fit into an inner bore hole of a stator and the bore hole of the hub sized to fit around without contacting an output shaft of an air motor of the generator, the plate also a trench on a bottom face and a plurality of mounting holes; a diffuser plate configured to attach to the bottom face of the hub with a plurality of air holes extending through the diffuser plate, the air holes being centered on the trench; a ring-shaped hub spacer in contact with a side of the diffuser plate opposite the hub.

A hub assembly for use in a compressed air driven inverter generator is provided. The hub assembly comprises: a hub comprising a plate with a cylindrical protrusion centered on a bottom face and a bore hole through the center of the plate and protrusion, the protrusion sized to fit into an inner bore hole of a stator and the bore hole of the hub sized to fit around without contacting an output shaft of an air motor of the generator, the plate also a trench on a bottom face and a plurality of mounting holes; a diffuser plate configured to attach to the bottom face of the hub with a plurality of air holes extending through the diffuser plate, the air holes being centered on the trench; a ring-shaped hub spacer in contact with a side of the diffuser plate opposite the hub.

A housing for a rotary engine has: a peripheral wall defining two end faces and an inner face transverse to the two end faces; two side walls sealingly engaged to the two end faces of the peripheral wall, a core of a side wall of the two side walls having a core face, the core face having a cavity section facing the rotor cavity and an abutment section annularly extending around the cavity section, the abutment section facing an end face of the two end faces, the abutment section having a flared portion flaring away from the end face; and a coating on the core face, the coating made of a material harder than a material of the core of the side wall, the coating covering the cavity section and ending at a coating edge located on the flared portion, the coating edge free of contact with the end face.