An internal combustion engine with a cylinder head and at least one piston-cylinder unit, in which, in a cylinder, a piston can be moved between a bottom and a top dead center position, where, in the cylinder, between the piston and the cylinder head a main combustion chamber is formed, which communicates with a prechamber which has a prechamber gas valve, and where the intake and outlet valves of the main combustion chamber are actuated by an actuator, where the prechamber gas valve is connected to a source for a gas-air mixture and the prechamber charge consists of a gas-air mixture with a lambda higher than 1.2, preferably higher than 1.5 and particularly preferably higher than 1.7, and the actuator is configured such that the intake valve closes before the piston reaches the bottom dead center position, where the piston is designed as a flat piston.

An internal combustion engine includes first and second common rails each having a metering or pressure regulating valve, with the valves settable at different pressure values from one another. Rotors are each sealingly and rotationally received within a respective cavity to define at least one combustion chamber of variable volume. The engine includes for each of the rotors a pilot subchamber in communication with the respective cavity, a pilot fuel injector in communication with the pilot subchamber, an ignition element positioned to ignite fuel within the pilot subchamber, and a main fuel injector in communication with the respective cavity at a location spaced apart from the pilot subchamber. Each main fuel injector is in fluid communication with the first common rail and each pilot fuel injector is in fluid communication with the second common rail. A method of combusting fuel in an internal combustion engine is also provided.

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.

An I.C. engine (and vehicles incorporating the same) connected with an air reservoir and having means of introducing water (or other evaporable fluid). The air reservoir can be used to store energy (in the form of compressed air) while braking the engine and/or allow compressed air to power the engine or to improve its performance. The evaporable fluid can be used: to increase engine efficiency, to increase power, for cooling, as a knock inhibitor, to allow an increased compression ratio, for NOx reduction, to effect other emissions, to aid in controlling HCCI, etc. The cooling effect of evaporable fluid is complementary to storing energy pneumatically since cooler air can be stored more efficiently. Other advantages are also discussed. This engine disclosure further contemplates means to recapture evaporable fluid for reuse (unburned hydrocarbons etc. may also be captured similarly).

An internal combustion engine includes first and second common rails each having a metering or pressure regulating valve, with the valves settable at different pressure values from one another. Rotors are each sealingly and rotationally received within a respective cavity to define at least one combustion chamber of variable volume. The engine includes for each of the rotors a pilot subchamber in communication with the respective cavity, a pilot fuel injector in communication with the pilot subchamber, an ignition element positioned to ignite fuel within the pilot subchamber, and a main fuel injector in communication with the respective cavity at a location spaced apart from the pilot subchamber. Each main fuel injector is in fluid communication with the first common rail and each pilot fuel injector is in fluid communication with the second common rail. A method of combusting fuel in an internal combustion engine is also provided.

An airway structure, a cylinder cover and a Miller-profile engine are provided. The airway structure includes an intake duct and an intake valve arranged on an intake side, and an exhaust duct and an exhaust side roof arranged on an exhaust side. An angle of an axis of an intake valve stem relative to an assembly bottom surface of the cylinder cover is a1; an angle between a revolution cone surface of an intake valve disc and the axis of the intake valve stem is a2, an angle between a plane where the exhaust side roof is located and the assembly bottom surface is a3, a lower guide surface of the intake duct close to an intake throat is inclined downward at an angle of a4 relative to the assembly bottom surface. The airway structure satisfies: a33a1-a2a3+3; and/or, a43a1-a2a4+3.

An airway structure, a cylinder cover and a Miller-profile engine are provided. The airway structure includes an intake duct and an intake valve arranged on an intake side, and an exhaust duct and an exhaust side roof arranged on an exhaust side. An angle of an axis of an intake valve stem relative to an assembly bottom surface of the cylinder cover is a1; an angle between a revolution cone surface of an intake valve disc and the axis of the intake valve stem is a2, an angle between a plane where the exhaust side roof is located and the assembly bottom surface is a3, a lower guide surface of the intake duct close to an intake throat is inclined downward at an angle of a4 relative to the assembly bottom surface. The airway structure satisfies: a3-3a1-a2a3+3; and/or, a4-3a1-a2a4+3.

A four-cycle internal combustion engine has a permanent curtailed intake process, which allows the temperature and pressure of intake air to the combustion cylinders to be tightly controlled, and enables a very small combustion chamber so that a much higher compression ratio and pre-ignition compression pressure can be achieved without approaching the air/fuel mixture auto-ignition threshold. The maximum threshold of curtailed intake volume is determined to be 68% of engine cylinder volume to achieve a compression ratio CR of 22.1 or higher. Because this design can effectively regulate and set the maximum pre-ignition temperature of the fuel-air mixture, it can combust virtually any type of liquid hydrocarbon fuel without knocking. This four-cycle engine, due to its higher compression ratio, generates power equivalent to or greater than a standard four-cycle engine in a smaller and lighter engine and at a much higher efficiency.

A system includes an internal combustion engine including a valve train comprising one or more intake valves operable in a Miller cycle and one or more exhaust valves. An electric turbo motor is electronically controllable to boost an output from a lower pressure turbocharger to a higher pressure turbocharger. An electronic control system configured to control the electric turbo motor in response to a transient condition to boost intake flow pressure to the internal combustion engine during the transient condition.

A system includes an internal combustion engine including a valve train comprising one or more intake valves operable in a Miller cycle and one or more exhaust valves. An electric turbo motor is electronically controllable to boost an output from a lower pressure turbocharger to a higher pressure turbocharger. An electronic control system configured to control the electric turbo motor in response to a transient condition to boost intake flow pressure to the internal combustion engine during the transient condition.