Operating a gaseous fuel engine system includes controlling at least one of a delivery location, a delivery timing, or in situ mixing of a gaseous fuel with air, based on at least one engine system parameter upon the basis of which a blowby amount of a gaseous fuel to a crankcase varies. Crankcase accumulation of the gaseous fuel is maintained below a flammability limit. Related apparatus and control logic is also disclosed.

Operating a gaseous fuel engine system includes outputting control commands to a first fuel admission valve and a second fuel admission valve to admit, respectively, a gaseous fuel blend containing a gaseous hydrogen fuel (H2), and additional H2, into a gaseous fuel engine. An amount of the additional H2 is determined by way of the respective control command based on a performance target for an engine parameter varying on the basis of a relative amount of H2 in a combustion charge. Related apparatus and control logic is also disclosed.

Operating a gaseous fuel engine system includes controlling at least one of a delivery location, a delivery timing, or in situ mixing of a gaseous fuel with air, based on at least one engine system parameter upon the basis of which a blowby amount of a gaseous fuel to a crankcase varies. Crankcase accumulation of the gaseous fuel is maintained below a flammability limit. Related apparatus and control logic is also disclosed.

An engine control system comprises a balancing arrangement together with a knock mitigation controller configured to implement a knock mitigation procedure wherein an offset input value (V.sub.I) is applied to the balancing algorithm. The offset input value (V.sub.I) may cause the balancing algorithm to adjust the control output (O.sub.1) for the respective one of the combustion chambers to progressively vary the fuel supply or ignition timing for the affected cylinder to mitigate the knock condition. Alternatively, the controller may generate an offset output value (V.sub.O) to more rapidly vary the fuel supply or ignition timing, with the offset input value (V.sub.I) being selected for example to compensate for the resulting change in the control input (I.sub.1) from the cylinder to the balancing algorithm, or to provide additional, more gradual adjustment to further mitigate the knock condition.

A method for entering and exiting cylinder deactivation modes in a diesel engine, comprises monitoring an engine speed from an idle engine speed to a governed engine speed and monitoring an engine load. If the monitored engine speed is the idle engine speed up to the governed engine speed, and if the engine load is less than the predetermined low load condition, then implementation of a cylinder deactivation mode is restricted to one of a 2 cylinder deactivation mode, a 3 cylinder deactivation mode, or a 4 cylinder deactivation mode. A cylinder deactivation mode is selected for engine operation among the 2 cylinder deactivation mode, the 3 cylinder deactivation mode, and the 4 cylinder deactivation mode to operate the engine at an effective frequency that avoids two resonant frequencies of the vehicle and to operate the engine below a torsional vibration limit.

The invention relates to a combustion gas injector assembly (1) comprising a combustion gas injector (3) having groups (11a,b,c) of combustion gas nozzle openings distributed around the periphery, each group having at least one combustion gas nozzle opening (13), a combustion gas nozzle valve member (9a,b,c) of the combustion gas injector (3), which member can be controlled in the open position and closed position, is associated with each group (11a,b,c) of combustion gas nozzle openings, in order to selectively discharge the combustion gas via the at least one combustion gas nozzle opening (13). The combustion gas injector assembly (1) is configured to control the combustion gas nozzle valve members (9a,b,c) successively with a predetermined time offset (T) into the closed position.

A method of controlling a gas engine connected to a turbocharger including a compressor and a turbine includes: performing a knocking control operation of optimizing an ignition timing as a steady operation; and in a case where a load of the gas engine increases during the steady operation, when a degree of increase in the load is relatively small, gradually increasing an actual fuel injection amount while keeping the ignition timing, and when the degree of increase in the load is relatively great, retarding the ignition timing and then gradually increasing the actual fuel injection amount.

The present disclosure relation relates to a system and method for controlling a gas engine, wherein the gas engine is supplied with a fuel gas which consists of different molecules and which is stored in at least a gaseous phase and a liquid phase in a gas storage device. The system comprises means for determining from which of its liquid or gaseous phase the fuel gas is taken out of the gas storage device. The system further comprises means for adapting the control of the gas engine in case it is determined that the phase from which the fuel gas is taken out of the gas storage device has changed.

A fuel injection device that injects a liquefied gas fuel from an injection port to a combustion chamber of the internal combustion engine includes a passage forming member configured to define a fuel passage through which the liquefied gas fuel flows to the injection port, a temperature regulating unit configured to adjust a temperature of the liquefied gas fuel flowing through the fuel passage according to an operation state of the internal combustion engine, and a pressure regulating unit configured to adjust a pressure of the liquefied gas fuel flowing through the fuel passage according to the operation state of the internal combustion engine.

A large two-stroke turbocharged compression-ignited internal combustion crosshead engine with a plurality of cylinders has at least one pressure booster for each cylinder for boosting fuel pressure, two or more electronically controlled fuel valves for each cylinder with an inlet of the two or more electronically controlled fuel valves being connected to an outlet of the at least one pressure booster. An electronic control unit is connected to the at least one pressure booster and the two or more electronically controlled fuel valves. The electronic control unit is configured to determine a start time for a fuel injection event, activate the at least one pressure booster ahead of the determined start time and pen the two or more electronically controlled fuel valves at the determined start time.