A variable geometry turbine having a wastegate includes a turbine housing, a power turbine, and a regulating valve. The turbine housing is provided with an inner intake gas flow channel and an outer intake gas flow channel. The turbine housing is further provided with a wastegate pipeline configured to bypass the power turbine, and a wastegate valve configured to control communication of the wastegate pipeline. One of the regulating valve and the wastegate valve has a regulating face having a varying axial height in a rotation direction of the regulating valve, and the other of the regulating valve and the wastegate valve has a linking portion which makes contact and cooperates with the regulating face. Thus, the efficiency of the turbine is improved significantly and backflow of the gas flow is reduced.

Techniques for controlling a forced-induction engine having a low pressure cooled exhaust gas recirculation (LPCEGR) system comprise determining a target boost device inlet pressure for each of one or more systems that could require a boost device inlet pressure change as part of their operation and boost device inlet pressure hardware limits for a set of components in the induction system, determining a final target boost device inlet pressure based on the determined sets of target boost device inlet pressures and boost device inlet pressure hardware limits, and controlling a differential pressure (dP) valve based on the final target boost device inlet pressure to balance (i) competing boost device inlet pressure targets of the one or more systems and (ii) the set of boost device inlet pressure hardware limits in order to optimize engine performance and prevent component damage.

Techniques for controlling a forced-induction engine having a low pressure exhaust gas recirculation (LPEGR) system comprise determining a desired differential pressure (dP) at an inlet of a boost device based on an engine mass air flow (MAF) and a speed of the engine, wherein the engine further comprises a dP valve disposed upstream from an EGR port and a throttle valve disposed downstream from the boost device, determining a desired EGR mass fraction based on at least the engine MAF and the engine speed, determining a maximum throttle inlet pressure (TIP) based on the engine speed, the desired EGR mass fraction, and a barometric pressure, and performing coordinated control of the dP valve and the throttle valve based on the desired dP and the maximum TIP, respectively, thereby extending EGR operability to additional engine speed/load regions and increasing engine efficiency.

One embodiment is a system comprising an internal combustion engine having one or more non-dedicated cylinders and one or more dedicated EGR cylinders configured to provide EGR to the engine via an EGR loop, a first spark plug coupled to each of the one or more non-dedicated cylinders, and a second spark plug coupled to each of the one or more dedicated EGR cylinders, wherein the second spark plug has a physical or dimensional characteristic that is different from the first spark plug. In certain forms each of the non-dedicated cylinders has only one of a first type of spark plug and each of the dedicated EGR cylinders has only one of a second type of spark plug. One or more of the characteristics that may vary between the first and second types of spark plugs include spark gap, electrode diameter, heat range, and ion sensing capability.

An internal combustion engine for use with a propeller driven aircraft includes a camshaft adapted to function as an output shaft that rotates a propeller to provide propulsive thrust. A gear set is configured to transfer rotational power from the crankshaft to the camshaft and to rotate the camshaft at a velocity that is proportional to the rotational velocity of the crankshaft. The gear set is disposed rearward of the engine housing rearward wall and is configured to rotate the camshaft in a direction opposite the crankshaft rotation. The length of the camshaft reduces engine torsional vibration. In one embodiment, the engine is a six-cylinder compression ignition engine having a boxer configuration and can generate a peak output power within a range from about 300 horsepower to about 350 horsepower.

A method for operating a multi-cylinder internal combustion engine in which every active cylinder operates in a four-stroke mode and every deactivated cylinder filled with an approximately completed gas filling is compressed and expanded during the four-stroke operation of the activated cylinder. In a method in which excitations of a crankshaft speed are minimized, a limited number of even-numbered cylinders of a multi-cylinder internal combustion engine (2) having a maximum even number of cylinders (20, 21, 22, 23, 24, 25) are deactivated sequentially, the limited even number of cylinders being smaller than the maximum even number of cylinders (20, 21, 22, 23, 24, 25) of the multi-cylinder internal combustion engine (2).

The first to ninth crank webs are roughly divided into three groups. The first group is from the second, fifth and eighth webs. These crank webs of the first group have similar shapes. In the crankshaft, the shapes of these crank webs belonging to the first group are adjusted to satisfy the first stiffness condition below.
First stiffness condition:the second and eighth webs>the fifth web W5

An internal combustion engine has a plurality of cylinders and transmission arranged adjoining the engine. If designating an average height of a combustion chamber in a region inside from a virtual cylindrical surface passing through center of a valve body of an intake valve and extending in a circumferential direction of each cylinder when a piston is at top dead center, as center height, and designating average of a height of the combustion chamber in a region outside from the virtual cylindrical surface when the piston is at top dead center, as peripheral height, the combustion chambers form a center height of a transmission side cylinder positioned most to the transmission side among the plurality of cylinders is higher than center heights of usual cylinders including one cylinder other than the transmission side cylinder and a peripheral height at the transmission side cylinder lower than peripheral heights of usual cylinders.

Exhaust systems are described. In examples, an exhaust flow path couples exhaust ports with one or more turbochargers of an engine. The exhaust flow path may have a portion flowing through a cylinder head (e.g., couplable to the exhaust ports) and a portion flowing through an exhaust manifold (couplable to the cylinder head and the turbocharger(s)). The flow paths may be shaped to reduce the sharpness of turns between the exhaust ports and the turbocharger(s). For example, curves along the flow path may be less than 90 degrees or have a minimum curve radius, which may vary along the flow path. Additionally, at least two, independent flow paths may exist between the exhaust ports and the turbocharger(s). The cross-sectional shape of any part of the flow path may be elliptical, including at inlets and outlets.

Exhaust systems are described. In examples, an exhaust flow path couples exhaust ports with one or more turbochargers of an engine. The exhaust flow path may have a portion flowing through a cylinder head (e.g., couplable to the exhaust ports) and a portion flowing through an exhaust manifold (couplable to the cylinder head and the turbocharger(s)). The flow paths may be shaped to reduce the sharpness of turns between the exhaust ports and the turbocharger(s). For example, curves along the flow path may be less than 90 degrees or have a minimum curve radius, which may vary along the flow path. Additionally, at least two, independent flow paths may exist between the exhaust ports and the turbocharger(s). The cross-sectional shape of any part of the flow path may be elliptical, including at inlets and outlets.