The invention relates to an internal combustion engine system. The system includes a mixing unit comprising a four-way valve. The four-way valve having a first inlet connected to the EGR line, a second inlet connected to the air inlet line, a first outlet connected to the first intake manifold and a second outlet connected to the second intake manifold. The four-way valve is designed so that, in said normal operating mode, the intake gases supplied to the first intake manifold and to the second intake manifold have approximately the same proportion of exhaust gas and fresh air and so that, in said cylinder deactivation mode, the intake gas supplied to the first intake manifold only includes exhaust gas and the fresh air is directed exclusively to the second intake manifold.

A valve assembly for an exhaust gas recirculation system includes a housing defining an inlet bore and including a second interior surface defining a housing bore. The valve assembly also includes a valve seat and a valve. The valve includes a valve stem and a valve sealing member. The valve assembly optionally includes a baffle at least partially disposed in the housing bore. A first interior radius is defined between the valve stem and the second interior surface. A second interior radius is defined between at least one of the valve stem and the second interior surface, the valve stem and the baffle, and the baffle and the second interior surface. The second interior radius is different from the first interior radius and is configured to direct the flow of the exhaust gas in the housing bore to reduce swirl of exhaust gas in the housing bore.

A valve assembly for an exhaust gas recirculation system includes a housing defining an inlet bore and including a second interior surface defining a housing bore. The valve assembly also includes a valve seat and a valve. The valve includes a valve stem and a valve sealing member. The valve assembly optionally includes a baffle at least partially disposed in the housing bore. A first interior radius is defined between the valve stem and the second interior surface. A second interior radius is defined between at least one of the valve stem and the second interior surface, the valve stem and the baffle, and the baffle and the second interior surface. The second interior radius is different from the first interior radius and is configured to direct the flow of the exhaust gas in the housing bore to reduce swirl of exhaust gas in the housing bore.

Disclosed are two system devices for stratified injecting the recirculated exhaust gas and high-specific-heat-capacity or inert gas for clean combustion of an internal combustion engine. The former is composed of an exhaust gas recirculation system, an injection system, and a power system. The latter is composed of four parts, and a high-specific-heat-capacity gas or inert gas channel is added. Injectors can be arranged at any position in the cylinder between a top dead center and a bottom dead center of a piston in a cylinder; 1-3 layers of injectors can be arranged; and 2-6 injectors can be arranged on each layer. Gas participating in combustion enters the cylinder from two intake channels, namely, a scavenging port of the internal combustion engine and the injectors; an in-cylinder swirl ratio can be remarkably increased through kinetic energy carried by the gas; and fuel-gas mixing is promoted, and the combustion rate is increased.

Disclosed are two system devices for stratified injecting the recirculated exhaust gas and high-specific-heat-capacity or inert gas for clean combustion of an internal combustion engine. The former is composed of an exhaust gas recirculation system, an injection system, and a power system. The latter is composed of four parts, and a high-specific-heat-capacity gas or inert gas channel is added. Injectors can be arranged at any position in the cylinder between a top dead center and a bottom dead center of a piston in a cylinder; 1-3 layers of injectors can be arranged; and 2-6 injectors can be arranged on each layer. Gas participating in combustion enters the cylinder from two intake channels, namely, a scavenging port of the internal combustion engine and the injectors; an in-cylinder swirl ratio can be remarkably increased through kinetic energy carried by the gas; and fuel-gas mixing is promoted, and the combustion rate is increased.

The invention relates to an internal combustion engine system. The system includes a mixing unit comprising a four-way valve. The four-way valve having a first inlet connected to the EGR line, a second inlet connected to the air inlet line, a first outlet connected to the first intake manifold and a second outlet connected to the second intake manifold. The four-way valve is designed so that, in said normal operating mode, the intake gases supplied to the first intake manifold and to the second intake manifold have approximately the same proportion of exhaust gas and fresh air and so that, in said cylinder deactivation mode, the intake gas supplied to the first intake manifold only includes exhaust gas and the fresh air is directed exclusively to the second intake manifold.

An internal combustion engine system including an internal combustion engine and an exhaust gas recirculation circuit connecting an exhaust manifold of the engine to an intake manifold of the engine, the circuit including at least one reed valve, an EGR valve, that is arranged downstream of the reed valve on the path of exhaust gas flowing from the exhaust manifold to the intake manifold and an EGR line connecting the reed valve to the EGR valve. The system further includes a bypass line for gas, connecting the EGR line to an exhaust line of the engine and controller for controlling the flow of gas discharged through the bypass line.

An internal combustion engine system including an internal combustion engine and an exhaust gas recirculation circuit connecting an exhaust manifold of the engine to an intake manifold of the engine, the circuit including at least one reed valve, an EGR valve, that is arranged downstream of the reed valve on the path of exhaust gas flowing from the exhaust manifold to the intake manifold and an EGR line connecting the reed valve to the EGR valve. The system further includes a bypass line for gas, connecting the EGR line to an exhaust line of the engine and controller for controlling the flow of gas discharged through the bypass line.

A method for operating an internal combustion engine includes operating at least one cylinder pre-chamber in a homogeneous charge compression ignition (HCCI) combustion mode by providing an air/fuel mixture in the pre-chamber that is fluidly connected to the at least one engine cylinder, creating H and OH radicals in the pre-chamber to achieve an ignition in the at least one pre-chamber, determining whether an ignition timing is advanced or delayed relative to a desired timing, and delaying the ignition when the ignition is advanced relative to the desired timing by cooling the pre-chamber and the at least one engine cylinder.

An exhaust gas recirculation (EGR) passage is connected with an intake passage (a bypass passage bypassing a supercharger) of an engine. The EGR passage includes, in a position close to a connection port to the intake passage, an expanding portion in which a passage cross-sectional area expands and which lowers a flow speed of EGR gas so as to reduce an uneven flow, in the connection port, of the EGR gas flowing into the intake passage.