An internal combustion engine includes a fuel nozzle for injecting a fuel into a combustion chamber, and a plasma igniter for generating one or more pluralities of free radicals within the chamber, and initiating a flame to ignite the fuel. The igniter protrudes into the chamber. A method of igniting a fuel within a combustion chamber and controlling combustion phasing includes injecting a first portion of the fuel into the combustion chamber, energizing the plasma igniter to generate one or more pluralities of free radicals, each plurality having a known voltage, subsequently injecting a second portion of the fuel into the combustion chamber, and closely coupling activation of the plasma igniter with the second injection to ignite the fuel. Combustion phasing of the ignition event is controlled by controlling the number and voltage of the pluralities of free radicals generated by the plasma igniter.

A control device for engine comprising; a variable valve operating mechanism (72) which comprises a cam (72d) and a pressure chamber (72c) internally filled with engine oil; and a hydraulic valve (72b) associated with the pressure chamber (72c) and configured to be opened and closed to control the oil pressure to be applied to an intake valve (22). When the engine load falls within a given low engine load range, the valve opening timing of the intake valve (22) is increasingly retarded according to the engine load and as the engine load becomes higher, within a limit of a given timing, and, when the engine load is increased beyond the given low engine load range, the valve opening timing of the intake valve is fixed to the given timing.

Methods, devices, controllers, and algorithms are described for operating an internal combustion engine wherein at least some firing opportunities utilize low temperature gasoline combustion (LTGC). Other firing opportunities may be skipped or utilize some other type of combustion, such as spark ignition. The nature of any particular firing opportunity is dynamically determined during engine operation, often on a firing opportunity by firing opportunity basis. Firings that utilize LTGC produce little, if any, nitrous oxides in the exhaust stream and thus, in some implementations, may require no aftertreatment system to remove them from the exhaust stream.

A control device for an internal combustion engine that includes an external EGR device having an EGR passage and an EGR valve installed at an end portion of the EGR passage on the side of a cylinder is configured, when a high intake air pressure condition is met and there is no EGR gas introduction request, to execute an EGR cut control using a variable valve operating device. In the EGR cut control, the control device is configured to open an intake valve during the intake stroke after the EGR valve opens, and adjust an overlap area such that an outflow gas amount via the EGR valve becomes equal to an inflow gas amount via the EGR valve. The EGR passage is configured so as to store a gas that flows out to the EGR passage from the cylinder via the EGR valve during of the EGR cut control.

A friction loss management system for an engine, comprises a combustion engine comprising a crankshaft and a plurality of cylinders, a reciprocating piston assembly connected to the crankshaft, a fuel injector connected to an injection controller, an intake valve connected to an intake valve controller, and an exhaust valve connected to an exhaust valve controller. A control unit comprises at least one set of control algorithms configured to receive engine power demand data, and determine a number of cylinders of the plurality of cylinders for deactivation based on the received engine power demand data and further based on sensed or stored friction values for the plurality of cylinders. Determining the number of cylinders of for deactivation minimizes friction between the plurality of cylinders and their respective reciprocating piston assembly by selecting a cylinder combination of active cylinders and deactivated cylinders with the lowest total friction while meeting engine power demand.

Various methods and systems are provided for reducing cylinder-to-cylinder variation in exhaust gas recirculation. In one embodiment, a system comprises a first cylinder group of an engine having a first number of cylinders, a second cylinder group of the engine having a second number of cylinders that is not an integer multiple of the first number of cylinders, and an exhaust system coupled to the first cylinder group and the second cylinder group. In at least one mode of operation, the exhaust system has exhaust ports of the first cylinder group fluidly coupled to an intake of the engine and exhaust ports of the second cylinder group fluidly decoupled from the intake.

Provided is a control device for an internal combustion engine, which can ensure a stable combustion state of the internal combustion engine even under a high-humidity environment condition, thereby improving the merchantability. The control device for the internal combustion engine includes an ECU (electronic control unit). The ECU calculates a basic target EGR amount according to an operating state of the internal combustion engine, calculates a water vapor amount in air drawn into an intake passage of the internal combustion engine, calculates an EGR conversion amount by using the water vapor amount, calculates a target EGR amount by subtracting the EGR conversion amount from the basic target EGR amount, and controls internal EGR and external EGR of the internal combustion engine by using the target EGR amount.

A friction loss management system for an engine, comprises a combustion engine comprising a crankshaft and a plurality of cylinders, a reciprocating piston assembly connected to the crankshaft, a fuel injector connected to an injection controller, an intake valve connected to an intake valve controller, and an exhaust valve connected to an exhaust valve controller. A control unit comprises at least one set of control algorithms configured to receive engine power demand data, and determine a number of cylinders of the plurality of cylinders for deactivation based on the received engine power demand data and further based on sensed or stored friction values for the plurality of cylinders. Determining the number of cylinders of for deactivation minimizes friction between the plurality of cylinders and their respective reciprocating piston assembly by selecting a cylinder combination of active cylinders and deactivated cylinders with the lowest total friction while meeting engine power demand.

It is a challenge to reduce unburned hydrocarbon emissions for gaseous fuelled engines, especially at low engine load conditions, to meet demanding emission regulation targets. A method for reducing unburned hydrocarbon emissions in a lean-burn internal combustion engine that is fuelled with a gaseous fuel comprises adjusting the timing for closing of an intake valve as a function of engine operating conditions by one of advancing timing for closing of the intake valve and closing the intake valve earlier during an intake stroke; and retarding timing for closing of the intake valve and closing the intake valve later during a compression stroke. The volumetric efficiency of the internal combustion engine is reduced and unburned hydrocarbon emissions are maintained below a predetermined level.

A system and method for cylinder deactivation in a multi-cylinder diesel engine comprises pumping air in to an intake manifold of the diesel engine using a turbocharger. Air is pumped in to the intake manifold using an intake air assisting device. And, fuel injection is selectively deactivated to at least one of the cylinders in the diesel engine. An intake valve and an exhaust valve is selectively deactivated for the at least one of the cylinders of the diesel engine.