The invention relates to an internal combustion engine system. The system includes a mixing unit comprising a four-way valve. The four-way valve having a first inlet connected to the EGR line, a second inlet connected to the air inlet line, a first outlet connected to the first intake manifold and a second outlet connected to the second intake manifold. The four-way valve is designed so that, in said normal operating mode, the intake gases supplied to the first intake manifold and to the second intake manifold have approximately the same proportion of exhaust gas and fresh air and so that, in said cylinder deactivation mode, the intake gas supplied to the first intake manifold only includes exhaust gas and the fresh air is directed exclusively to the second intake manifold.

The present invention provides a closed-loop control method for an electronic fuel injection piston-engine on an unmanned aircraft consisting of the following steps: determination of a set of control coefficients; preliminary determination of fuel injection flow; determination of the injection limit; determination of the actual injectable value; perform fuel injection; the opening of the air intake valve is controlled to ensure that the fuel-air ratio always remains within a specified range. The present invention also provides a method for modeling the operation of an engine at each operating range. In addition, the method of physically simulating the operating conditions according to the pressure ranges of the engine is also proposed. The simulation method to find the control coefficients corresponding to each operating model of the engine is presented, the fuel injection closed-loop control structure is built on a control simulation software.

Methods and systems are provided for cylinder deactivation to reduce tailpipe emissions and increase exhaust temperature. In one example, a method may include operating a first set of cylinders in a first combustion cycle over modified eight strokes and a second set of cylinders in a second combustion cycle over modified four strokes. Each cylinder in the first set of cylinders may be selectively deactivated via a variable displacement engine (VDE) mechanism while each cylinder in the second set of cylinders may be selectively deactivated via an active decompression technology (ADT) mechanism.

An internal combustion engine having an engine control configured to operate in first and second operating modes. The first operating mode is configured to leave as many ignition devices deactivated per cycle in dependence on the currently present power demand. The second operating mode is configured to reduce a risk of deflagration due to unburned gas-air mixture present in an exhaust stroke. After a first number (N.sub.1) of cycles, for a second number (N.sub.2) of cycles, the second operating mode has more piston-cylinder units produce power per cycle than required for the currently present power demand. After the second number (N.sub.2) of cycles, for a third number (N.sub.3) of cycles, in dependence on a currently present power demand per cycle, the second operating mode has so many piston-cylinder units produce power that this results in a torque of the crankshaft adapted to the currently present power demand.

A crawled vehicle comprising: an internal combustion engine; an engine compartment wherein the internal combustion engine is housed; an air inlet opening to catch air from the outside of the crawled vehicle; a first channel, for cold air, connected and fed by the air inlet opening with air coming from outside the crawled vehicle; a second channel to be fed with hot air coming from the internal combustion engine; a third channel for air, coupled to the internal combustion engine to feed the internal combustion engine with air; an air filter arranged along the third channel and upstream of the internal combustion engine; a connection element connected to the first channel, to the second channel and third channel; and an air adjusting device to adjust the air temperature in the third channel and comprising a shutter coupled to the first channel and/or to the second channel and/or to the connection element; and a control device controlling a position of the shutter to adjust the temperature of the air entering the third channel.

According to one or more embodiments presently described, a method of operating an internal combustion engine that includes injecting fuel into a combustion chamber to form an air-fuel mixture, where the combustion chamber includes a cylinder head, cylinder sidewalls, and a piston that reciprocates within the cylinder sidewalls. The method may also include detecting pre-ignition of the air-fuel mixture during a detected intake or compression stroke of the piston, determining that a super knock condition could occur, and mitigating formation of a super knock condition by deploying a super knock countermeasure within the detected compression stroke.

An engine assembly comprising an internal combustion engine having a combustion chamber; an intake manifold for supplying air to the combustion chamber; a fuel injector for supplying fuel to the combustion chamber; an exhaust manifold for receiving exhaust gas released from the combustion chamber and a rotatable drive shaft, wherein combustion of fuel in air within the combustion chamber results in rotation of the drive shaft. The engine assembly further comprises a turbocharger system comprising a turbine and a compressor, wherein the turbine is configured to receive exhaust gas from the exhaust manifold, to recover energy from the exhaust gas, and to release the exhaust gas via a turbine outlet; and wherein the compressor is configured to receive energy from the turbine and thereby to compress air for use in combustion of fuel in the combustion chamber. An intake throttle valve is configured to selectively control a boost pressure by controlling supply of air to the intake manifold; and a bypass valve is configured to selectively divert exhaust gas from the exhaust manifold away from the turbine, wherein the bypass valve is controlled by the boost pressure. A controller is configured (a) to provide an intermediate value for desired valve position of the intake throttle valve based on a desired oxygen to fuel ratio; and (b) to output a final value for desired valve position of the intake throttle valve based on the intermediate value for desired valve position and an engine speed value.

A speed control device which is satisfactory in response and tracking to a speed setting, and can adjust an acceleration-and-deceleration feel according to preferences, is provided. The speed control device 6 controls a speed of a ship so that the speed automatically follows a speed setting set by a ship operator. The speed control device 6 includes a target speed setting module 63 and a change rate adjusting module 64. The target speed setting module 63 sets a target speed that is a target of the speed of the ship to follow, for every unit time, according to the speed setting, to change the target speed based on a given rate of change. The change rate adjusting module 64 decreases the rate of change by adjusting the rate of change at multiple stages, when the target speed set by the target speed setting module 63 approaches the speed setting.

An engine intake system includes: a port partition disposed to divide an intake port of a cylinder head into an upper portion and a lower portion; a first intake manifold configured to supply air, which flows from an air cleaner through a charger and an intercooler, to one of the upper portion and the lower portion of the port partition; a second intake manifold configured to supply the air, which flows from the air cleaner while bypassing the charger and the intercooler, to the other of the upper portion and the lower portion of the port partition; and a bypass valve disposed and configured to pass and block the air flowing into the second intake manifold from the air cleaner.

Throttle-at-valve apparatus, internal combustion engines employing throttle-at-valve apparatus, and methods of throttling an internal combustion engine using a throttle-at-valve apparatus, where the throttle-at-valve apparatus includes a throttle slide body disposed within a throttle slide cavity that is defined between and in fluid communication with both an unobstructed air intake passage and an intake valve of an internal combustion engine, where the air flow from the air intake passage to the intake valve is regulated by the reciprocal movement of the throttle slide body within the throttle slide cavity.