An improved air-cooled aviation engine includes a compact combustion chamber having an intake valve opening, an exhaust valve opening, and a generally elliptical shape. The elliptical shape has a major axis and a minor axis, with the major axis intersecting both the intake valve opening and the exhaust valve opening. In some examples, the major axis is the same length or shorter than a diameter of a cylinder bore of the engine, and the minor axis is smaller than the major axis. Combustion is thus constrained to a smaller area than that of the cylinder bore.

A damper device and a total heat exchanger including the same are provided in the present application, including: a damper plate, including an air port cover plate, and a rotating shaft disposed at the air port cover plate and extending along a diameter direction of the air port cover plate; and a damper plate fixing base configured to fix the damper plate inside the damper plate fixing base and including a fixing groove formed opposite to the rotating shaft and configured to fix the rotating shaft, the fixing groove including a recess disposed opposite to the rotating shaft and formed by further being recessed from at least a part of the outer circumference of the fixing groove. According to the above technical solutions of the present application, the damper device can ensure performance without reducing the air volume under low temperature conditions, and can also suppress icing of the damper device.

A damper device and a total heat exchanger including the same are provided in the present application, including: a damper plate, including an air port cover plate, and a rotating shaft disposed at the air port cover plate and extending along a diameter direction of the air port cover plate; and a damper plate fixing base configured to fix the damper plate inside the damper plate fixing base and including a fixing groove formed opposite to the rotating shaft and configured to fix the rotating shaft, the fixing groove including a recess disposed opposite to the rotating shaft and formed by further being recessed from at least a part of the outer circumference of the fixing groove. According to the above technical solutions of the present application, the damper device can ensure performance without reducing the air volume under low temperature conditions, and can also suppress icing of the damper device.

An engine system which combines an internal combustion engine with a unique air-cooling system. The air-cooling system includes a cooling cylinder(s) which is disposed in the engine block. Input air is expanded through the cooling cylinder from the intake manifold directly to the exhaust manifold. No high compression or combustion takes place in the cooling cylinder. Heat from the cooling cylinder is transferred to the input air, and the heated air is then exhausted to the internal combustion engine exhaust stream where it is used to help power a turbocharger.

A system and methods for a vehicle are provided for adjusting each of a speed of a radiator fan and a position of grille shutters of the vehicle responsive to a temperature at a wastegate exceeding a temperature threshold. In one example, a system may include a radiator fan at a front end of a vehicle, an engine coupled to an exhaust passage, a turbine in the exhaust passage having a bypass conduit, a wastegate positioned in the turbine conduit, and the wastegate receiving airflow from downstream of the radiator fan via a cooling duct.

A system and methods for a vehicle are provided for adjusting each of a speed of a radiator fan and a position of grille shutters of the vehicle responsive to a temperature at a wastegate exceeding a temperature threshold. In one example, a system may include a radiator fan at a front end of a vehicle, an engine coupled to an exhaust passage, a turbine in the exhaust passage having a bypass conduit, a wastegate positioned in the turbine conduit, and the wastegate receiving airflow from downstream of the radiator fan via a cooling duct.

A damper device and a total heat exchanger including the same are provided in the present application, including: a damper plate, including an air port cover plate, and a rotating shaft disposed at the air port cover plate and extending along a diameter direction of the air port cover plate; and a damper plate fixing base configured to fix the damper plate inside the damper plate fixing base and including a fixing groove formed opposite to the rotating shaft and configured to fix the rotating shaft, the fixing groove including a recess disposed opposite to the rotating shaft and formed by further being recessed from at least a part of the outer circumference of the fixing groove. According to the above technical solutions of the present application, the damper device can ensure performance without reducing the air volume under low temperature conditions, and can also suppress icing of the damper device.

A damper device and a total heat exchanger including the same are provided in the present application, including: a damper plate, including an air port cover plate, and a rotating shaft disposed at the air port cover plate and extending along a diameter direction of the air port cover plate; and a damper plate fixing base configured to fix the damper plate inside the damper plate fixing base and including a fixing groove formed opposite to the rotating shaft and configured to fix the rotating shaft, the fixing groove including a recess disposed opposite to the rotating shaft and formed by further being recessed from at least a part of the outer circumference of the fixing groove. According to the above technical solutions of the present application, the damper device can ensure performance without reducing the air volume under low temperature conditions, and can also suppress icing of the damper device.

The internal combustion engine includes a fan cover that covers a cooling fan driven by a crankshaft, a top cover that covers the fan cover, and a cooling air passage between the fan cover and the top cover. The fan cover includes a first rib facing the top cover in the cooling air passage.

In a hollow exhaust poppet valve including a fillet increasing in diameter toward a leading end, a stem, and a head and having a coolant within a hollow part formed from the head to the stem, the stem includes a first stem part on a base end side, and a second stem part integrated with the first stem part via a step part and integrated with the fillet, and the hollow part includes a first hollow part formed inside the first stem part, and a second hollow part formed inside the second stem part, the fillet, and the head in such fashion as to have a constant inner diameter greater than the first hollow part and formed so as to be continuous with the first hollow part via a tapered part or a curved part.