To solve the problems of compressor wheel blade flow separation causing surge type noises when an exhaust gas recirculation (EGR) duct introduces into the compressor exhaust gases to be returned to the engine, the exhaust gas is fed into an annular volume, defined between inner and outer walls or an annular transition cavity shaped as a radially expanded, axially flattened cylindrical space in the compressor inlet, so that the generally unidirectional radial flow from an EGR duct is re-directed and organized as it is turned from generally radial to generally axial, merging with the general inlet flow and presenting the compressor wheel with airflow of “circumferentially uniform” flow velocity.

An EGR passage, an EGR valve that is provided in the EGR passage, and an opening degree controller that controls an opening degree of the EGR valve based on an operating state of the internal combustion engine are included. The opening degree controller determines whether or not there is a possibility of an exhaust outlet of the exhaust passage being submerged in water, and when it is determined that there is the possibility of the exhaust outlet being submerged in water, the opening degree controller controls the opening degree of the EGR valve to a closing side as compared with a case where it is determined that there is no possibility of being submerged in a same operating state.

Methods and systems are provided for controlling exhaust flow and recovering heat from exhaust gas under different operating conditions. In one example, motive flow of fresh air via an ejector coupled to an exhaust bypass assembly may be utilized to divert exhaust through a heat exchanger during cold-start conditions and heat extracted from the exhaust gas may be utilized for passenger cabin heating and other vehicle heating demands. The exhaust bypass assembly may also be used for EGR delivery wherein the exhaust heat exchanger may be used as an EGR cooler.

Methods and systems are provided for controlling exhaust flow and recovering heat from exhaust gas under different operating conditions. In one example, motive flow of fresh air via an ejector coupled to an exhaust bypass assembly may be utilized to divert exhaust through a heat exchanger during cold-start conditions and heat extracted from the exhaust gas may be utilized for passenger cabin heating and other vehicle heating demands. The exhaust bypass assembly may also be used for EGR delivery wherein the exhaust heat exchanger may be used as an EGR cooler.

A control device estimates a leakage gas amount with respect to gas that leaks to an upstream side from a downstream side of a fresh air introduction valve when the fresh air introduction valve is closed. If the leakage gas amount is equal to or greater than a predetermined value when there is a request to open the fresh air introduction valve, a target opening degree of the fresh air introduction valve is determined based on the engine speed and intake pressure, and also a correction opening degree with respect to the target opening degree is calculated based on the leakage gas amount. The fresh air introduction valve is opened to an opening degree greater than the target opening degree by an amount corresponding to the correction opening degree, to thereby cause leakage gas that is accumulated in a fresh air introduction passage to flow into an intake passage together with a required amount of fresh air.

A control device estimates a leakage gas amount with respect to gas that leaks to an upstream side from a downstream side of a fresh air introduction valve when the fresh air introduction valve is closed. If the leakage gas amount is equal to or greater than a predetermined value when there is a request to open the fresh air introduction valve, a target opening degree of the fresh air introduction valve is determined based on the engine speed and intake pressure, and also a correction opening degree with respect to the target opening degree is calculated based on the leakage gas amount. The fresh air introduction valve is opened to an opening degree greater than the target opening degree by an amount corresponding to the correction opening degree, to thereby cause leakage gas that is accumulated in a fresh air introduction passage to flow into an intake passage together with a required amount of fresh air.

A method of controlling a rate of warm-up of an internal combustion engine fluidly connected to an exhaust system is disclosed. The method includes identifying a cold-start of the engine. The method also includes regulating, in response to the identified cold-start of the engine, an exhaust pressure modulation (EPM) valve arranged in a main exhaust passage of the exhaust system. The main exhaust passage channels engine exhaust gas to the ambient. Such regulation of the EPM valve will restrict a flow of the engine exhaust gas to the ambient and increase exhaust gas backpressure in the exhaust system up to a predetermined pressure value. Furthermore, the subject regulation of the EPM valve will increase a load on and the rate of warm-up of the engine. A vehicle having an engine and a controller programmed to control a rate of the engine's warm-up of according to the method is also disclosed.

An exhaust system includes a diesel oxidation catalyst (DOC) device mounted to an exhaust pipe for exhausting an exhaust gas of an engine and purifying hydrocarbon (HC) and carbon monoxide (CO) among the exhaust gas, an urea injector positioned at a rear of the diesel oxidation catalyst device for injecting an urea aqueous solution to an inside of the exhaust pipe, a mixer positioned at the rear of the urea injector, a diesel particulate matter filter (DPF) positioned at the rear of the mixer and coated with a catalyst devoid of a noble metal or a hydrolysis catalyst that does not oxidize ammonia and hydrolyzes the injected urea to reduce a particulate material of the exhaust gas, and a selective catalytic reduction (SCR) device positioned at the rear of the diesel particulate matter filter.

An apparatus for retrieving exhaust heat of an engine, may include the engine including a plurality of combustion chambers, an intake line, an exhaust line, a turbocharger including, a turbine provided on the exhaust line, and a compressor provided on the intake line and compressing external air, an exhaust gas recirculation (EGR) apparatus including an EGR line branched from the exhaust line at a rear end of the turbocharger and merged with the intake line, an EGR cooler disposed on the EGR line, and an EGR valve to adjust an amount of re-circulated exhaust gas, an intercooler to cool the intake gas introduced through the intake line, an intercooler cooling line passing through a radiator and the intercooler, an EGR cooling line passing through the radiator and the EGR cooler, an EGR exhaust line, and an exhaust adjusting valve disposed on the EGR exhaust line.

An apparatus for retrieving exhaust heat of an engine, may include the engine including a plurality of combustion chambers, an intake line, an exhaust line, a turbocharger including, a turbine provided on the exhaust line, and a compressor provided on the intake line and compressing external air, an exhaust gas recirculation (EGR) apparatus including an EGR line branched from the exhaust line at a rear end of the turbocharger and merged with the intake line, an EGR cooler disposed on the EGR line, and an EGR valve to adjust an amount of re-circulated exhaust gas, an intercooler to cool the intake gas introduced through the intake line, an intercooler cooling line passing through a radiator and the intercooler, an EGR cooling line passing through the radiator and the EGR cooler, an EGR exhaust line, and an exhaust adjusting valve disposed on the EGR exhaust line.