The exhaust gas recirculation (EGR) system provided herein utilizes a crossover (X) valve that is selectively activated at the direction of the electronic control module (ECM) to mix the high temperature (HT) and low temperature (LT) circuits of the EGR system under certain predetermined operating conditions. Thus, HT circuit fluid (at engine temperatures) is selectively fed into the LT circuit fluid (at ambient temperatures) to heat certain LT circuit components that are normally cooled by the LT circuit before starting the low pressure (LP) EGR in certain cold cycles. When this heating is finished, the X valve is closed to provide normal HT circuit/LT circuit fluid separation. The X valve can be controlled using a rotational actuator or the like. To avoid exposing the LT circuit to the high revolution-per-minute (RPM) operating conditions of the HT circuit, a HT bypass mechanism is provided.

The exhaust gas recirculation (EGR) system provided herein utilizes a crossover (X) valve that is selectively activated at the direction of the electronic control module (ECM) to mix the high temperature (HT) and low temperature (LT) circuits of the EGR system under certain predetermined operating conditions. Thus, HT circuit fluid (at engine temperatures) is selectively fed into the LT circuit fluid (at ambient temperatures) to heat certain LT circuit components that are normally cooled by the LT circuit before starting the low pressure (LP) EGR in certain cold cycles. When this heating is finished, the X valve is closed to provide normal HT circuit/LT circuit fluid separation. The X valve can be controlled using a rotational actuator or the like. To avoid exposing the LT circuit to the high revolution-per-minute (RPM) operating conditions of the HT circuit, a HT bypass mechanism is provided.

A mixer for a gas flow system, such as an exhaust gas recirculation system, is provided. In one example, a gas flow system for an engine includes a first passage through which a first gas is configured to flow along a first axis; a second passage through which a second gas is configured to flow along a second axis, the first passage fluidly coupled to the second passage at an outlet of the first passage; and a mixer integrated with the first passage at the outlet and extending into the second passage, the mixer including an extension extending radially around the first axis and a main body extending into the second passage along the first axis.

A gas-liquid separator includes an inlet pipe and an inner pipe. The inlet pipe includes a swirling flow generating member therewithin, and a first drain port through which the liquid exits. The inner pipe includes an opening at an end which is inserted into an end of the inlet pipe. The swirling flow generating member includes a vane supporting portion extending along an axis line of the inlet pipe, and stator vanes provided on an outer circumferential surface of the vane supporting portion. The vane supporting portion has a conical shape whose diameter gradually increases from a fluid entering side to a fluid exiting side of the gas-liquid two-phase fluid. The stator vanes surround the outer circumference with inclining relative to the axis line of the inlet pipe.

A gas-liquid separator includes an inlet pipe and an inner pipe. The inlet pipe includes a swirling flow generating member therewithin, and a first drain port through which the liquid exits. The inner pipe includes an opening at an end which is inserted into an end of the inlet pipe. The swirling flow generating member includes a vane supporting portion extending along an axis line of the inlet pipe, and stator vanes provided on an outer circumferential surface of the vane supporting portion. The vane supporting portion has a conical shape whose diameter gradually increases from a fluid entering side to a fluid exiting side of the gas-liquid two-phase fluid. The stator vanes surround the outer circumference with inclining relative to the axis line of the inlet pipe.

A method for operating an oxycombustion engine system includes passing a nitrogen-depleted gas, a fuel, and a recycled exhaust gas into a combustion chamber, combusting a mixture of the nitrogen-depleted gas, the fuel, and the recycled exhaust gas, thereby producing an exhaust gas including carbon dioxide, detecting a pressure of the recycled exhaust gas passed to the combustion chamber, determining whether the detected pressure of the recycled exhaust gas is less than a configurable pressure threshold, and in response to determining that the detected pressure of the recycled exhaust gas is less than the configurable pressure threshold, increasing the pressure of the recycled exhaust gas passed to the combustion chamber.

A method for operating an oxycombustion engine system includes passing a nitrogen-depleted gas, a fuel, and a recycled exhaust gas into a combustion chamber, combusting a mixture of the nitrogen-depleted gas, the fuel, and the recycled exhaust gas, thereby producing an exhaust gas including carbon dioxide, detecting a pressure of the recycled exhaust gas passed to the combustion chamber, determining whether the detected pressure of the recycled exhaust gas is less than a configurable pressure threshold, and in response to determining that the detected pressure of the recycled exhaust gas is less than the configurable pressure threshold, increasing the pressure of the recycled exhaust gas passed to the combustion chamber.

The invention relates to an internal combustion engine system (100), comprising: —an internal combustion engine (2) comprising a cylinder block (3) housing a plurality of cylinders (4), a first intake manifold (6a) connected to a first group of cylinders (4a) a second distinct intake manifold (6b) connected to a second group of cylinders (4b) and a first, respectively a second, exhaust manifold (8a, 8b) for receiving the exhaust gas emitted from the first, respectively the second, group of cylinders (4a, 4b); —an air inlet line (10); —an EGR line (20) connected to the first and second exhaust manifolds (8a, 8b); wherein the internal combustion engine system is operable in at least two operating modes, respectively a normal operating mode in which all cylinders are supplied with fuel and a regeneration operating mode, in which the cylinders of the first group of cylinders (4a) are no longer supplied with fuel, characterized in that: —the system also includes a mixing unit (30) comprising a four-way valve, said four-way valve (30) having a first inlet (31) connected to the EGR line (20), a second inlet (32) connected to the air inlet line (10), a first outlet (33) connected to the first intake manifold (6a) and a second outlet (34) connected to the second intake manifold (6b); —the four-way valve is designed so that, in said normal operating mode, the intake gases supplied to the first intake manifold (6a) and to the second intake manifold (6b) have approximately the same proportion of exhaust gas and so that, in said regeneration operating mode, the intake gas supplied to the first intake manifold (6a) only includes exhaust gas.

The invention relates to an internal combustion engine system (100), comprising: —an internal combustion engine (2) comprising a cylinder block (3) housing a plurality of cylinders (4), a first intake manifold (6a) connected to a first group of cylinders (4a) a second distinct intake manifold (6b) connected to a second group of cylinders (4b) and a first, respectively a second, exhaust manifold (8a, 8b) for receiving the exhaust gas emitted from the first, respectively the second, group of cylinders (4a, 4b); —an air inlet line (10); —an EGR line (20) connected to the first and second exhaust manifolds (8a, 8b); wherein the internal combustion engine system is operable in at least two operating modes, respectively a normal operating mode in which all cylinders are supplied with fuel and a regeneration operating mode, in which the cylinders of the first group of cylinders (4a) are no longer supplied with fuel, characterized in that: —the system also includes a mixing unit (30) comprising a four-way valve, said four-way valve (30) having a first inlet (31) connected to the EGR line (20), a second inlet (32) connected to the air inlet line (10), a first outlet (33) connected to the first intake manifold (6a) and a second outlet (34) connected to the second intake manifold (6b); —the four-way valve is designed so that, in said normal operating mode, the intake gases supplied to the first intake manifold (6a) and to the second intake manifold (6b) have approximately the same proportion of exhaust gas and so that, in said regeneration operating mode, the intake gas supplied to the first intake manifold (6a) only includes exhaust gas.

A mixture formation device for an internal combustion engine operated with a burnable gas, preferably compressed natural gas CNG, comprises a combination of a quantity regulator, a gas mixer, a flow-guiding element for pressure recovery, and a connection possibility for exhaust gas recirculation of the internal combustion engine. The mixture formation device according to the invention can empty a gas tank to a comparatively low pressure of approx. 2 bar, an excellent mixture formation being achieved over the entire range of speed and load range of the internal combustion engine. According to the invention, such a mixture formation device can reduce production costs as well as space requirements compared to known solutions. An internal combustion engine operated with a burnable gas, particularly compressed natural gas (CNG), may also comprise such a mixture formation device in the intake tract thereof.