An engine system may include main exhaust ports fluidly communicated with each combustion chamber, main exhaust valves opening and closing each main exhaust port, a main exhaust manifold connected with the main exhaust ports, scavenge exhaust ports fluidly communicated with the each combustion chamber, scavenge valves opening and closing the each scavenge exhaust port, a scavenge manifold connected with the scavenge exhaust ports, in which at least a part of an exhaust gas passing through the scavenge manifold is re-circulated to the combustion chamber to be burned.

A controller calculates a specific humidity of an intake air based on a relative humidity of the intake air, an intake air temperature, and an intake air pressure. Then the controller calculates a water vapor amount in the intake air based on the specific humidity and a mass flow rate of the intake air obtained from an air intake rate. By calculating the water vapor amount in the intake air based on information that directly represents the status of the intake air, this water vapor amount may be calculated more accurately. As a result, a generation amount of condensed water may be estimated more accurately. Therefore, accumulation of condensed water may be suppressed while recirculating as much of a low pressure exhaust gas as possible, and thus fuel economy may be sufficiently improved.

A controller calculates a specific humidity of an intake air based on a relative humidity of the intake air, an intake air temperature, and an intake air pressure. Then the controller calculates a water vapor amount in the intake air based on the specific humidity and a mass flow rate of the intake air obtained from an air intake rate. By calculating the water vapor amount in the intake air based on information that directly represents the status of the intake air, this water vapor amount may be calculated more accurately. As a result, a generation amount of condensed water may be estimated more accurately. Therefore, accumulation of condensed water may be suppressed while recirculating as much of a low pressure exhaust gas as possible, and thus fuel economy may be sufficiently improved.

This disclosure relates to a waste heat recovery (WHR) system and method for regulating exhaust gas recirculation (EGR) cooling, and more particularly, to a Rankine cycle WHR system and method, including a recuperator bypass arrangement to regulate EGR exhaust gas cooling for engine efficiency improvement and thermal management. This disclosure describes other unique bypass arrangements for increased flexibility in the ability to regulate EGR exhaust gas cooling.

An exhaust gas recirculation device for an engine including a plurality of cylinders and intake branch passages is provided. The exhaust gas recirculation device includes an exhaust chamber and distribution passages for the respective cylinders. The exhaust chamber is connected to an exhaust passage of the engine, and exhaust gas from the exhaust passage is introduced into the exhaust chamber. The distribution passages connect the exhaust chamber to the intake branch passages for the respective cylinders so as to recirculate the exhaust gas back into the intake branch passages. The flow passage area of a first portion of each of the distribution passages is smaller than the flow passage area of a second portion of each of the distribution passages. The first portion is connected to the corresponding intake branch passage, and the second portion is connected to the exhaust chamber.

A housing has an outer pipe, an inner pipe, and an EGR inlet. The inner pipe is located inside the outer pipe. The inner pipe defines an inner passage internally. The inner pipe defines an annular passage externally with the outer pipe. The EGR inlet defines an EGR channel therein to communicate with the annular passage. The inner pipe has an end surface defining a throttle passage extending circumferentially. The throttle passage communicates the annular passage with the inner passage radially inward. The throttle passage is narrow on a side of the EGR channel and is wide on an opposite side of the EGR channel.

Methods and systems are provided for an auto-ignition internal combustion engine comprising an exhaust gas recirculation arrangement, an intake system, and an exhaust gas discharge system for the discharge of exhaust gases, in which the internal combustion engine is operable, at least in a first, stoichiometric operating mode, by way of a spatial ignition method (HCCI mode). For the aftertreatment of the exhaust gas in the first operating mode, a three-way catalytic converter is provided in the exhaust gas discharge system for reducing nitrogen oxides and oxidizing unburned hydrocarbons and carbon monoxide. In this way, the auto-ignition internal combustion engine has a greater window of operation in the HCCI mode than conventional auto-ignition internal combustion engines.

An engine system having donor cylinders and non-donor cylinders is disclosed. The engine system may have a first intake manifold configured to distribute air into the non-donor cylinders, and a second intake manifold configured to distribute air into the donor cylinders. The engine system may also have a first exhaust manifold configured to discharge exhaust from the non-donor cylinders to the atmosphere, and a second exhaust manifold separate from the first exhaust manifold and configured to recirculate exhaust from the donor cylinders to the first intake manifold. The engine system may further have an orifice disposed in between the first intake manifold and the second intake manifold. The orifice may be configured to regulate a flow rate of fluid flowing from the first intake manifold to the second intake manifold. The engine system may further have a controller configured to selectively control the orifice in response to a desired exhaust gas recirculation operating condition.

The disclosure relates to an exhaust gas conduction system for a gasoline engine, comprising an exhaust gas line which can be connected to an exhaust manifold of the gasoline engine, an intake line which can be connected to an intake manifold of the gasoline engine, a charge air compressor which is arranged in the intake line, and a turbine which is arranged in the exhaust gas line. The exhaust gas line has at least one bypass line with a bypass throttle valve, said line branching off from the exhaust gas line upstream of the turbine and branching back into the exhaust gas line at an opening downstream of the turbine. At least one exhaust gas recirculation line with an EGR throttle valve is provided, said line opening into the intake line, wherein the exhaust gas recirculation line branches off from the bypass line at a branch, and the bypass throttle valve is arranged upstream of the branch of the exhaust gas recirculation line. At least one particle filter is arranged in the bypass line downstream of the branch of the exhaust gas recirculation line, and an exhaust gas valve is provided in the exhaust gas line upstream of the opening of the bypass line.

The disclosure relates to an exhaust gas conduction system for a gasoline engine, comprising an exhaust gas line which can be connected to an exhaust manifold of the gasoline engine, an intake line which can be connected to an intake manifold of the gasoline engine, a charge air compressor which is arranged in the intake line, and a turbine which is arranged in the exhaust gas line. The exhaust gas line has at least one bypass line with a bypass throttle valve, said line branching off from the exhaust gas line upstream of the turbine and branching back into the exhaust gas line at an opening downstream of the turbine. At least one exhaust gas recirculation line with an EGR throttle valve is provided, said line opening into the intake line, wherein the exhaust gas recirculation line branches off from the bypass line at a branch, and the bypass throttle valve is arranged upstream of the branch of the exhaust gas recirculation line. At least one particle filter is arranged in the bypass line downstream of the branch of the exhaust gas recirculation line, and an exhaust gas valve is provided in the exhaust gas line upstream of the opening of the bypass line.