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 coolant collector bracket including a front side, a back side, and a top side is provided. The back side is opposite the front side and includes a plurality of coolant inlets for receiving coolant from a cylinder head. The top side includes an exhaust gas recirculation (EGR) cooler inlet and an EGR coolant outlet. The EGR coolant inlet and the EGR coolant outlet are substantially orthogonal to the plurality of coolant inlets.

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.

Methods and systems are provided for determining changes in a flow area of an exhaust gas recirculation (EGR) valve for EGR flow estimates due to soot accumulation on the EGR valve. In one example, a method includes indicating soot accumulation on the EGR valve based on a difference in EGR flow estimated with an intake oxygen sensor and with a pressure sensor coupled across the EGR valve. The determination of the difference of the EGR flow estimates may occur when the engine is not boosted.

An engine system includes main exhaust ports fluidly communicating with each combustion chamber. An exhaust variable valve lift apparatus controls an operation of a main exhaust valve which closes or opens each main exhaust port. A main exhaust manifold is connected with the main exhaust ports. Scavenge exhaust ports fluidly communicate with each combustion chamber. A variable scavenge apparatus controls an operation of a scavenge valve which closes and opens each scavenge exhaust port. A scavenge manifold is connected with the scavenge exhaust ports. A controller is configured to control operations of the exhaust variable valve lift apparatus and the variable scavenge apparatus according to a vehicle operation state.

An engine system includes main exhaust ports fluidly communicating with each combustion chamber. An exhaust variable valve lift apparatus controls an operation of a main exhaust valve which closes or opens each main exhaust port. A main exhaust manifold is connected with the main exhaust ports. Scavenge exhaust ports fluidly communicate with each combustion chamber. A variable scavenge apparatus controls an operation of a scavenge valve which closes and opens each scavenge exhaust port. A scavenge manifold is connected with the scavenge exhaust ports. A controller is configured to control operations of the exhaust variable valve lift apparatus and the variable scavenge apparatus according to a vehicle operation state.

Methods and systems are provided for adjusting a location of a fuel injection in response to a substitution rate and a desired EGR flow. In one example, a method may include injecting a first fuel to a combustion chamber via a direct injector positioned to inject directly into the combustion chamber, injecting a second, different, fuel to the combustion chamber via an exhaust port injector positioned to inject toward an exhaust valve of the combustion chamber, and combusting the first and second fuels together in the combustion chamber.

An engine system having an exhaust gas recirculation apparatus, the engine system including an engine including a plurality of combustion chambers that generates a driving power by combusting fuel, an intake line into which intake gas to be supplied into the combustion chamber flows, an exhaust line through which exhaust gas discharged from the combustion chamber flows, a turbocharger including a turbine provided in the exhaust line and rotated by exhaust gas discharged from the combustion chamber, and a compressor provided in the intake line and rotated in conjunction with the rotation of the turbine and compressing outside air, an EGR apparatus including an EGR line that branches off from the exhaust line at a rear end of the turbocharger and merges into the intake line, and an EGR cooler disposed in the EGR line for cooling exhaust gas flowing through the EGR line, a waste gate valve installed in an exhaust bypass line, which branches off from a front end of the turbine and merges into a rear end of the turbine, and adjusts an amount of exhaust gas flowing into the turbine, and a recirculation valve installed in an intake bypass line, which branches off the intake line at a front end of the engine and merges into the intake line at a front end of the compressor, and supplies a part of the intake gas, which is compressed by the turbocharger, into the intake line at the front end of the compressor.

An engine system having an exhaust gas recirculation apparatus, the engine system including an engine including a plurality of combustion chambers that generates a driving power by combusting fuel, an intake line into which intake gas to be supplied into the combustion chamber flows, an exhaust line through which exhaust gas discharged from the combustion chamber flows, a turbocharger including a turbine provided in the exhaust line and rotated by exhaust gas discharged from the combustion chamber, and a compressor provided in the intake line and rotated in conjunction with the rotation of the turbine and compressing outside air, an EGR apparatus including an EGR line that branches off from the exhaust line at a rear end of the turbocharger and merges into the intake line, and an EGR cooler disposed in the EGR line for cooling exhaust gas flowing through the EGR line, a waste gate valve installed in an exhaust bypass line, which branches off from a front end of the turbine and merges into a rear end of the turbine, and adjusts an amount of exhaust gas flowing into the turbine, and a recirculation valve installed in an intake bypass line, which branches off the intake line at a front end of the engine and merges into the intake line at a front end of the compressor, and supplies a part of the intake gas, which is compressed by the turbocharger, into the intake line at the front end of the compressor.