Internal combustion engine, preferably a gas engine, comprising a pre-chamber having a pre-chamber intake system and a main combustion chamber having a main combustion chamber intake system, wherein by use of the intake systems a predetermined amount of energy of fuel can be supplied to the main combustion chamber for a combustion, wherein a control unit is configured to control the intake systems according to the following operation modes: a first operation mode, in which a majority of a fuel energy amount for the combustion in the main combustion chamber is supplied directly to the main combustion chamber by use of the main combustion chamber intake system, and a second operation mode, in which a majority of the fuel energy amount for the combustion in the main combustion chamber is supplied via the pre-chamber to the main combustion chamber by use of the pre-chamber intake system.

An engine assembly including an engine core including at least one internal combustion engine each including a rotor sealingly and rotationally received within a respective internal cavity to provide rotating chambers of variable volume in the respective internal cavity, a compressor having an outlet in fluid communication with an inlet of the engine core, a first intake conduit in fluid communication with an inlet of the compressor and with a first source of air, a second intake conduit in fluid communication with the inlet of the compressor and with a second source of air warmer than the first source of air, and a selector valve configurable to selectively open and close at least the fluid communication between the inlet of the compressor and the first intake conduit. A method of supplying air to a compressor is also discussed.

An intercooler drain system which drains condensate from an intercooler includes an upper header, a lower header, and a plurality of tubes connecting the upper header and the lower header, the intercooler drain system including: a drain passage allowing the condensate collected in the lower header of the intercooler to be drained; and a valve opening and closing the drain passage. The valve has a specific gravity less than a specific gravity of the condensate, and when the condensate is collected above a predetermined level in the lower header, the valve rises due to buoyancy to open the drain passage.

An intake-air temperature controlling device is provided, which includes an engine body, an intake passage, a supercharger, a first passage, a second passage, an intake air flow rate adjuster, an intercooler, a pump, and a controller. The controller outputs a control signal to the pump so that coolant is supplied to the intercooler in a first operating range in which the intake air flow rate adjuster at least partially opens the first passage to supply intake air boosted by the supercharger to the engine body, and outputs a control signal to the pump so that the coolant is supplied to the intercooler also in a second operating range in which an engine load is below a given load, and the intake air flow rate adjuster opens the second passage and closes the first passage to supply the intake air to the engine body in a non-boosted state.

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 compressor housing accommodating a compressor wheel for compressing intake air supplied to an engine has therein an outer cooling passage extending along a circumferential direction on an outer circumferential side of a scroll passage of a spiral shape through which the intake air compressed by the compressor wheel flows, and an inner cooling passage extending along the circumferential direction on an inner circumferential side of the scroll passage. The inner cooling passage is separated from the outer cooling passage by a separation wall extending along the circumferential direction.

A bottom surface of a surge tank has such a shape that, in a vehicle-mounted state, the bottom surface is positioned below a lower surface at an upstream end of each of a plurality of independent passages and comes closer to the lower surface at the upstream end of each of the plurality of independent passages in a vertical direction farther away from a connected portion between the surge tank and a third passage in a cylinder array direction.

An engine system may include an engine including a plurality of combustion chambers for generating a driving force by combustion of fuel, an exhaust gas purification device mounted in an exhaust line through which exhaust gas discharged from the combustion chamber flows, an EGR gas collecting device configured for collecting a part of the exhaust gas from an exhaust manifold of the engine and supplying the exhaust gas to an intake manifold of the engine, and an EGR gas supply control valve provided between the EGR gas collecting device and the intake manifold and adapted to regulate a flow rate of EGR gas supplied to the intake manifold.

A conventional gasoline engine is retrofitted and calibrated to operate as a bi-fuel engine using Hydrogen as the second fuel. When operated with Hydrogen, which typically leads to a reduction of engine output power, the engine is preferably operated in a charged mode and in a lean mode with the engine throttle kept in a wide open position during charged and lean mode operation resulting in a more efficient engine with a reduction of engine output power loss.

Apparatuses, systems and methods are disclosed for separating oil from a blow-by gas of an engine. An example includes engine system includes a crankcase having a blow-by gas passing therethrough, a compressor configured to receive air and compress the air, an aftercooler, an oil separating apparatus and a jet pump. The aftercooler communicates with the compressor and is configured to cool at least a portion of the air compressed by the compressor. The oil separating apparatus communicates with the blow-by gas. The oil separating apparatus communicates with a boost air that is a mixture of the compressed air from the compressor and cooled air from the aftercooler. The jet pump communicates with both the blow-by gas after leaving the oil separating apparatus and the boost air after leaving the oil separating apparatus and is configured to combine the blow-by gas and the boost air.