Abstract: A fuel injector includes a nozzle assembly having a nozzle case, and a concentric check assembly within the nozzle case. Transfer passages are formed in an outer check of the check assembly, and spray orifices are formed in the nozzle case. A fuel volume is formed between the outer check and an inner check, and the inner check is movable to fluidly connect the transfer passages to the fuel volume. The outer check is rotatable between a first angular orientation and a second angular orientation to fluidly connect separate sets of the transfer passages to separate sets of the spray orifices. Spray ducts are in spray path alignment with at least one of the sets of spray orifices.

Abstract: A piston of an internal combustion engine configured to be reciprocable along an axial direction in a cylinder includes a cavity formed to be recessed in a center of a piston top surface, and an outer circumferential edge portion located on a radially outer side of the cavity in the piston top surface. The cavity includes a lip portion, a raised portion, and a curved portion. The curved portion includes an outer circumference-side curved surface which includes a curved surface connected to the lip portion, an inner circumference-side concave surface which is located on a radially inner side of an outer circumference-side curved surface and includes a surface connected to a raised portion, the inner circumference-side concave surface including a deepest portion of the cavity, and a convex surface formed between the outer circumference-side curved surface and the inner circumference-side concave surface, as well as protruding upward.

Abstract: An electronic control unit of an internal combustion engine is configured to, when cooling fuel is supplied to a combustion chamber, calculate a target amount of supply of the cooling fuel and calculate a first upper limit injection amount that is an upper limit of an amount of fuel allowed to be injected from a second valve as the cooling fuel, when the target amount of supply is less than or equal to the first upper limit injection amount, supply the cooling fuel in the entire target amount of supply from the second valve to the combustion chamber in a first mode in which single-stage injection is performed, and, when the target amount of supply is greater than the first upper limit injection amount, supply the cooling fuel to the combustion chamber in a second mode in which the cooling fuel more easily diffuses than in the first mode.

Abstract: The use as a valve deposit controlling additive in a fuel composition for a direct injection spark-ignition internal combustion engine of a combination of: a) at least one hydrocarbyl-substituted aromatic compound; and b) at least one polyalkylene amine.

Abstract: A method for operating an internal combustion engine of a motor vehicle having a cylinder, the combustion chamber of which is delimited in the radial direction by a cylinder wall and in the axial direction by a piston and by a combustion chamber roof. The piston has an annularly peripheral piston stage which is arranged axially recessed in the piston compared with an annularly peripheral piston crown and which merges via an annularly jet splitter contour into a piston hollow arranged axially recessed in the piston in relation to the piston stage. An injector is allocated to the cylinder and via the injector several injection jets are simultaneously injected directly into the combustion chamber in a star shape for a combustion process.

Abstract: A controller may obtain data indicative of heat release in a cylinder of an engine. The controller may determine that the data indicative of the heat release in the cylinder is indicative of clogging of one or more ducts of a duct structure of the engine. The controller may perform an operation to reduce the clogging of the one or more ducts based on the data indicative of the heat release in the cylinder being indicative of the clogging of the one or more ducts. The operation may include at least one of causing a pressure of fuel that is supplied to a fuel injector to increase or causing a peak temperature in the cylinder to increase.

Abstract: An internal combustion engine system includes an engine housing having a combustion cylinder, and a piston movable within the combustion cylinder to increase a pressure therein to an autoignition threshold for injected fuel. The piston includes a piston crown having a combustion face forming a combustion bowl, and varied in profile to form jet-jet interaction limiters at locations offset from fuel spray jet paths from a fuel injector. The jet-jet interaction limiters include a bowl component and a step component protruding, respectively, within the combustion bowl and a step located transitioning between the combustion bowl and a circumferential rim of the piston. Limiting jet-jet interaction limits soot production in exhaust produced by the engine.

Abstract: Methods and systems are provided for diagnosis of oil dilution in an engine. In one example, a method may include sealing a crankcase and spinning an engine unfueled to heat and vaporize the oil in response to detection of rich engine operation. Pressure measurements at the sealed crankcase may be collected and compared to a baseline to diagnose a presence of fuel in the oil.

Abstract: An ignition system for a gaseous fuel engine includes an igniter and an actuator structured to apply an actuating force to a piston within the igniter, to autoignite an ignition charge of fuel and air within the igniter. A housing of the igniter includes a gas orifice having a flow area that is increased between a combustion pre-chamber in the igniter and a main combustion chamber in the engine, to limit velocity of outgoing combustion gases to below a threshold velocity for engine mis-fire.

Abstract: Operating an internal combustion engine includes conveying fuel of spray plumes of directly injected fuel out of a swirl pocket in a combustion bowl in a piston, and impinging the fuel upon an anti-sooting ramp transitioning between a radially inner shelf surface of the combustion bowl and a radially outer squish surface of the piston. The shelf surface is spaced an axial distance (FA) from a plane defined by the squish surface that is from 1% to 2% of an outer diameter (OD) dimension of the piston. Impinging the fuel upon the anti-sooting ramp directs the fuel upwardly from the squish surface to limit wall-wetting in the combustion cylinder.

Abstract: Methods and systems are provided for controlling vehicle operating parameters depending on whether the vehicle is operating within an area defined by an adjustable geographical boundary, the adjustable geographical boundary defined based on wireless communication between vehicles and infrastructures. In one example, a method comprises determining that the vehicle has entered into an area defined by the adjustable boundary, and adjusting a control mapping of an acceleration control of the vehicle in response to the determining. In this way, fuel economy, emissions, and customer satisfaction may be improved.

Abstract: The engine control method includes a fuel supply step and an ignition step. In the fuel supply step, the injector supplies fuel into a combustion chamber. In the ignition step, an spark plug arranged in the combustion chamber makes a flame after the supply of the fuel into the combustion chamber and at a timing when a flow strength in the combustion chamber is greater than a predetermined value in a compression stroke during or before a post-mid stage where the compression stroke is divided into four stages of a pre-stage, a pre-mid stage, a post-mid stage, and a post-stage.

Abstract: A combustion chamber structure for an engine includes a combustion chamber where SI combustion by spark ignition and CI combustion by self-ignition are conducted. A crown surface includes a cavity recessed to have a bowl-shape; a pair of first raised portions having a mound-shape along a pent roof shape; and a second raised portion provided to protrude at a position orthogonal to a ridge extending direction of the pair of first raised portions. With a height of the first raised portion relative to a height position of a deepest portion of the cavity being represented as H1 and a height of the second raised portion being represented as H2, H1/H2 as a ratio of the height H1 of the first raised portion to the height H2 of the second raised portion is set to be in a range of 1.92 or more and 2.75 or less.

Abstract: A fuel injection device including a valve body having an injection hole-formed part having a plurality of injection holes on the leading end side of the valve body. An injection hole comprises a crossing angle, ?1, between a central axis of the injection hole-formed part and an injection hole axis, and another injection hole comprises a crossing angle, ?2, between the central axis and another injection hole axis. ?2 is larger than ?1. The injection holes are formed such that a distance between the central axis and an inlet surface center of the injection hole is longer than a distance between the central axis and another inlet surface center of the another injection hole. A straight line beyond an outlet surface in the injection hole axis does not intersect with another straight line beyond another outlet surface in the another injection hole axis.

Abstract: A fuel injection device is provided with reduced adherence of fuel spray with respect to an intake valve, a wall surface in an engine cylinder, or a piston. The fuel injection device includes a valve body and a seat surface to perform sealing of fuel cooperatively and injection holes. Inlet opening surfaces are formed on the seat surface. A first injection hole and a second injection hole arranged closest to the first injection hole. The first injection hole is larger than the second injection hole in an injection hole angle to be an angle formed by a normal direction of the seat surface and a center axis of the injection hole. The second injection hole is larger than the first injection hole in an area of a cross-section perpendicular to the center axis of the injection hole.

Abstract: In a spark-ignition internal combustion engine in which a protrusion including an intake-side inclined surface and an exhaust-side inclined surface is formed on a top surface of a piston, and a cavity is formed in the protrusion at a position associated with a spark plug, the intake-side inclined surface and the exhaust-side inclined surface are formed in such a way that a ratio of a length of the exhaust-side inclined surface with respect to a length of the intake-side inclined surface is 1.25 or larger in a cross section passing through a center axis of the piston and orthogonal to an axis direction of a crankshaft.

Abstract: A piston for an internal combustion engine includes a crown portion having a bowl that includes a plurality of protrusions. Each of the plurality of protrusions includes a first side surface and a second side surface. Other features including at least one ledge formed between protrusions in segments, and a generally flat, inward facing surface on the protrusions may also be used.

Abstract: Various technologies presented herein relate to heating a fuel and enhancing fuel and charge-gas mixing inside a combustion chamber to enable minimal, or no, generation of soot and/or other undesired emissions during ignition and subsequent combustion of the locally premixed mixtures. To enable sufficient mixing of the fuel and charge-gas, a jet of fuel can be directed to pass through a bore of a duct causing charge-gas to be drawn into the bore creating turbulence to mix the fuel and the drawn charge-gas. The duct can be heated to provision heating of the fuel and charge-gas mixture. The duct can be located proximate to an opening in a tip of a fuel injector. An ignition assist component can be located downstream of the duct to facilitate ignition of the fuel/charge-gas mixture.

Abstract: A control system of a compression-ignition engine is provided, which includes an engine configured to cause combustion of a mixture gas inside the combustion chamber, an injector attached to the engine and configured to inject fuel into the combustion chamber, a spark plug disposed to be oriented into the combustion chamber and configured to ignite the mixture gas inside the combustion chamber, and a controller connected to the injector and the spark plug and configured to operate the engine by outputting a control signal to the injector and the spark plug, respectively. After the spark plug ignites the mixture gas to start combustion, unburned mixture gas combusts by self-ignition. The controller outputs the control signal to the injector so that a fuel injection timing is advanced when the engine operates at a high speed than at a low speed.

Abstract: Examples are directed to a fuel injection device positioned in a cylinder liner. In one example, a cylinder includes a combustion chamber which is jointly formed by a piston crown of a piston, by a cylinder barrel which laterally delimits the combustion chamber, and by a cylinder head. The cylinder includes an injection device positioned in the cylinder barrel for direct introduction of fuel into the combustion chamber, which injection device has at least one opening which, during a course of an injection process, is configured to be activated to introduce fuel into the combustion chamber, the injection device terminating flush, at a combustion chamber side, with the cylinder barrel.

Abstract: When it is determined that the igniting environment is out of the desired range, the variable valve mechanism is controlled so that the swirl ratio is increased. When the swirl ratio becomes high, the discharge spark and the initial flame move largely in the flow direction of the swirl flow SW and approach the closest fuel spray. Therefore, the discharge spark and the initial flame are attracted to the closest fuel spray and the initial flame enlarges by involving the closest fuel spray (middle stage of FIG. 7). Further, the initial flame enlarges further by involving surrounded fuel spray (lower stage of FIG. 7).

Abstract: The present invention relates to a combustion chamber structure of an engine configured to inject fuel in a predetermined operation range in a period from a second half of a compression stroke until a first half of an expansion stroke to perform ignition after a compression top dead center. The combustion chamber structure includes: a piston including a cavity; a fuel injection valve provided at a middle portion of the piston; and a spark plug provided at a radially outer side of the middle portion of the piston and an upper side of the cavity. The cavity is formed by a curved surface having curvature that becomes larger as the curved surface extends toward the radially outer side. A tangential direction of an edge end portion of the curved surface intersects with a combustion chamber ceiling radially outward of the spark plug.

Abstract: A direct fuel injection internal combustion engine having an injector for directly injecting fuel into a combustion chamber thereof is provided. The engine is configured so that a tumble flow is generated in the combustion chamber. A fuel injection by the injector can be performed in a first injection mode and a second injection mode, the first injection mode being a mode in which the fuel injection is completed after the tumble flow is generated, and the second injection mode being a mode in which the fuel injection is completed before the tumble flow is generated. The fuel injection of the first injection mode is performed before completion of the warming-up of the engine, and the fuel injection of the second injection mode is performed after completion of the warming-up of the engine.

Abstract: In a catalyst warming-up control, a first time injection is performed by an injector in an intake stroke. A second time injection is performed with an amount smaller than the first time injection in an expansion stroke after a compression top dead center. In the catalyst warming-up control, an interval from the start of the ignition period of an spark plug to the completion of the second time injection is controlled by the ECU so that the initial flame generated from an air-fuel mixture containing the fuel spray injected by the first time injection is brought into contact with the fuel spray injected by the second time injection.

Abstract: A flexible-fuel internal combustion engine apparatus comprises a combustion chamber, an intake valve, a first fuel injector, a second fuel injector, and a computer. The intake valve is operable to admit an intake charge into the combustion chamber. The first fuel injector injects a gaseous fuel directly into the combustion chamber. The second fuel injector injects a liquid fuel into the intake charge upstream of the intake valve. The computer is operatively connected with the first fuel injector and the second fuel injector to actuate injection of fuel respectively therefrom. The computer is programmed to command a gaseous-to-liquid fuel ratio as a function of at least one operating parameter from a group comprising gaseous fuel pressure, gaseous fuel mass, engine speed, engine torque, inlet air temperature, inlet air humidity, knock detection, operating history, torque command, and emissions.

Abstract: A ducted combustion system is disclosed. The ducted combustion system includes a combustion chamber bound by a flame deck surface of a cylinder head of an internal combustion engine and by a piston top surface of a piston disposed within the internal combustion engine. The system includes a fuel injector including one or more orifices, the one or more orifices injecting fuel into the combustion chamber as one or more fuel jets. The system includes one or more adjustable length ducts disposed within the combustion chamber between the flame deck surface and the piston top surface, the one or more adjustable length ducts being disposed such that each of the one or more fuel jets, at least partially, enters one of the one or more adjustable length ducts upon being injected into the combustion chamber.

Abstract: A fuel injector injecting a fuel toward a combustion chamber mounted to a gasoline engine is provided with plural injection ports through which the fuel is injected. Each injection port includes an injection-port axial line limiting a pointing direction of the injection port, and the injection-port axial lines point to different directions. The injection ports include at least one intake injection port the injection-port axial line of which points to an intake space in the combustion chamber between a top surface of a piston of the internal combustion engine and an intake valve of the internal combustion engine. The intake injection port is defined by an inner peripheral wall surface extending in the injection-port axial line of the intake injection port and having a straight shape.

Abstract: It is an object of the present invention to reduce the penetration of a fuel spray directed toward a certain area in a cylinder, thereby reducing oil dilution that increases sliding resistance in the engine, reducing fuel adhesion or the like onto the cylinder liner, and also reducing the adverse effect of a fuel spray having an increased penetration. A fuel injection valve that has a plurality of injection holes and injects fuel into a cylinder 3 of an internal combustion engine includes: injection holes a2 and a6 having a larger diameter for injecting fuel toward a ring-shaped space T1 including areas A2 and A6 of strong tumble flow T formed in the cylinder; and injection holes a1, a4, a3 and a5 having a smaller diameter for injecting fuel toward a space including areas A1, A4, A3 and A5 of weak tumble flow formed in the cylinder 3.

Abstract: A piston for balancing combustion efficiency and smoke generation with NOx production includes a combustion face forming a combustion bowl having a compound curvature increased in sharpness in a radially outward direction. An outer bowl surface defines a large radius of curvature adjacent an inner bowl surface, and a medium radius of curvature adjacent a cylindrical wall surface. The inner bowl, outer bowl, and wall surfaces together contour the combustion bowl, such that a diameter of the combustion bowl is about 124 mm so as to establish a bowl to bore ratio of about 0.71 in a direct injection compression ignition engine with a compression ratio of about 15:1 to 17:1.

Abstract: An internal-combustion engine includes a cylinder, a piston, a spark plug, and a fuel injection device. The piston includes a top surface, a guiding protrusion, and a cavity. The cavity is provided at a position closer to the fuel injection device than the guiding protrusion when viewed from above the top surface of the piston. The guiding protrusion includes a guiding surface to guide the fuel mist toward the spark plug when the fuel mist is injected from the fuel injection device at a first predetermined timing in a compression stroke. The cavity includes a guiding wall portion to guide the fuel mist toward the spark plug when the fuel mist is injected from the fuel injection device at a timing in the compression stroke between the first predetermined timing and a second predetermined timing.

Abstract: A fuel injection duct for a combustion apparatus is provided. The fuel injection duct includes an inlet opening, an outlet opening, and an inner surface, wherein the inner surface exhibits a surface structure imparting a swirl to fuel moving from the inlet opening to the outlet opening, the fuel interacting with the surface structure of the inner surface. The manufacture of the fuel injection duct is easy and cost-effective and imparts a swirl to fuel flowing through the fuel injection duct.

Abstract: A gasoline engine control system includes a crankshaft rotation sensor configured to measure a rotation speed of a crankshaft, a coolant temperature sensor configured to measure a coolant temperature, an engine knocking sensor, a valve timing mechanism, an engine igniter, an air/fuel controller, and a controller configured to obtain a crankshaft rotation speed, a coolant temperature, and knocking information from the crankshaft rotation sensor, the coolant temperature sensor, and the engine knocking sensor, respectively, to determine a fuel class flowing in the engine and a cold start adaption factor, determine a fuel/cold start adaption factor based on the fuel class and the cold start adaption factor, and control an operation of at least one of the valve timing mechanism, the engine igniter, and the air/fuel controller according to the determined fuel/cold start adaption factor when the determined fuel/cold start adaption factor may be not a predetermined reference fuel/cold start adaption factor.

Abstract: A fuel system for an engine having a cylinder liner is disclosed. The fuel system may have a gaseous fuel injector having a nozzle located at an air intake port of the cylinder liner. The gaseous fuel injector may be configured to inject gaseous fuel radially into the cylinder liner at an oblique vertical angle with respect to a plane perpendicular to an axis of the cylinder liner. The fuel system may also have a liquid fuel injector configured to inject liquid fuel axially into the cylinder liner.

Abstract: There is provided efficient compression auto-ignition combustion over intermediate load range extended towards a low and high load range. An internal combustion engine enables compression auto-ignition combustion by securing a so-called sealed duration created by negative valve overlap. It includes a cylinder head, a cylinder, a piston in the cylinder having a top coupled to the cylinder head, a combustion chamber between an inner surface of a cylinder head and a top of the piston, and intake and exhaust valves. Two intake valves are arranged per each combustion chamber and made to differ in valve lift.

Abstract: An internal combustion engine has a cylinder, a cylinder head mounted to the cylinder, a piston disposed in the cylinder, and a fuel injection valve. A combustion chamber is defined by the piston, the cylinder head and the cylinder. The fuel injection valve has a plurality of injection holes that injects fuel directly inside the cylinder from a side of the combustion chamber. The injection holes inject fuel in a spray shape with an overall shape, which is formed by a plurality of sprays being injected from the injection holes. The overall shape expands toward the cylinder head and forms one part of a conical shape that is dented near the piston. Central axes of some of the injection holes are oriented toward a boundary portion near the exhaust valve formed at a crown surface of the piston and an inner wall of the cylinder when fuel is injected.

Abstract: An internal combustion engine includes an engine block having a cylinder bore and a cylinder head having a flame deck surface disposed at one end of the cylinder bore. A piston connected to a rotatable crankshaft and configured to reciprocate within the cylinder bore has a piston crown portion facing the flame deck surface such that a combustion chamber is defined within the cylinder bore and between the piston crown and the flame deck surface. A fuel injector having a nozzle tip disposed in fluid communication with the combustion chamber has at least one nozzle opening configured to inject a fuel jet into the combustion chamber along a fuel jet centerline. At least one duct defined in the combustion chamber between the piston crown and the flame deck surface has a generally rectangular cross section and extends in a radial direction relative to the cylinder bore substantially along the fuel jet centerline.

Abstract: Fuel is injected into and through the exhaust port and into the cylinder of the piston engine during the time when the flow is reversed from the normally expected flow. The engine is able to operate with some or all of its fuel injected backwards of conventional expectations. In another embodiment the fuel is injected with solid stream injector sprays directed against exhaust valves and ports and deflected into the piston cylinder against the flow of normally aspirated or supercharged engines. This invention can apply to gasoline or diesel cycles and four and two stroke type cycles of engine.

Abstract: A diesel combustion system including an injector and a combustion chamber. The combustion chamber is formed by a cylinder head, a cylinder liner, and a piston. The combustion chamber includes an upper layer and a lower layer. The diameter D1 of the upper layer is larger than the diameter D2 of the lower layer. A junction of the upper layer and the lower layer is provided with an impinging block for rebounding the diesel fuel spray. The impinging block includes an impinging surface, an upper guide surface, and a lower guide surface. When in use, part of the diesel fuel spray is rebounded by the impinging surface, and part of the diesel fuel spray is diffused along the upper guide surface and the lower guide surface of the impinging block to achieve double-layered split flow of the diesel fuel.

Abstract: A direct injection engine includes a fuel injector receiving a flow of pressurized fuel. The fuel injector provides fuel injections directly into a combustion chamber of the engine. The fuel injector includes a first fuel injector nozzle opening directing with a first narrow injection angle a first portion of a fuel injection mass at a spark gap of a spark plug. The fuel injector further includes a second fuel injector nozzle opening dispersing with a second wider injection angle a second portion of the fuel injection mass within the combustion chamber.

Abstract: A method of improving the combustion of a spark-ignition internal combustion engine. Such engines have at least one cylinder, each cylinder having a compression chamber and operated such that an air-fuel mixture introduced into the combustion chamber is ignited to cause a combustion event. An antenna is placed within the combustion chamber, and is used to apply electromagnetic energy to the combustion.

Abstract: A piston for an internal combustion engine, for example a diesel engine, including a body delimited laterally by a skirt and configured to collaborate with walls of a cylinder of axis of revolution C in which the piston can slide along the axis C, the piston including a transverse face including a central pip, a peripheral ring, and a bowl of axis of revolution B that extends from the central pip towards the peripheral ring to which it connects at a lip of thickness Ep, the bowl including, in substantial vertical alignment with the lip, a torus in profile, for example of dome-shaped, of maximum radius capable of guiding fuel injected under the lip in the region of a re-entrant zone towards the central pip. The tip of the central pip exhibits a flattened region centred on the axis of revolution B of the bowl, of a width Lt ranging between 0 mm and 5 mm, or substantially equal to 2.5 mm.

Abstract: A fuel injector-igniter incorporating adaptive swirl injection and ignition. The fuel injector-igniter comprises a housing, an actuator, and a valve. The valve includes a valve head operative to open and close against a valve seat in response to activation of the actuator. The valve seat includes an electrode portion extending beyond the valve head and within the housing to form at least one gap, such as an annular gap. A current discharge between the housing and electrode portion establishes a plasma and electromagnetic forces driving the plasma from the gap. The injector-igniter may further comprise a power supply connected to the housing and valve seat that is operative to provide the current discharge. The electrode portion includes a plurality of flow shaping features, such as a plurality of twisted fins disposed around the electrode portion and thereby operative to impart a rotation to the plasma.

Abstract: Passageways are provided within the combustion chamber of a fuel injected internal combustion engine to convey injected fuel to desired positions within the combustion chamber. The fuel-conveying passageways may be either open-sided or closed, and are positioned within the combustion chamber in substantial alignment with a respective spray jet of fuel, enabling optimum distribution of the fuel through the combustion chamber for enhanced mixing with air prior to combustion.

Abstract: In a direct fuel-injection engine equipped with a pentroof-shaped piston, cross-sectional shapes containing a piston central axis (Lp) of a cavity recessed in a central part of the piston having a top face with the height varying in the circumferential direction are set so as to be basically identical at each position in the circumferential direction (see broken line).

Abstract: In a direct injection spark ignition internal combustion engine that includes a fuel injection valve, and closes an intake valve after gas in the combustion chamber begins to flow back into an intake passageway after the compression stroke begins. The required fuel injection amount is injected a first fuel injection and a second fuel injection in a single combustion cycle, and the first fuel injection is performed while the intake valve is open during the compression stroke, and the second fuel injection is performed after the intake valve closes. The timing of the first fuel injection is set such that the injected fuel is deflected upwards in the top of the combustion chamber by the gas flowing toward the intake valve.

Abstract: In a combustion space of a combustion engine, an inlet valve to supplies a gaseous medium which contains oxygen to the combustion space. A movable piston to compress the gaseous medium in the combustion spaces. An injector injects fuel in the combustion space in a jet which comprises a multiplicity of small fuel drops. The injector injects fuel in the combustion space at such a high initial velocity that the fuel injected in the jet mixes with the gaseous medium to form a substantially homogeneous mixture before the mixture has been decelerated to a velocity at which the fuel ignites and burns. Devices may cool the gaseous medium and the fuel before entry into the combustion space.

Abstract: An internal combustion engine electrically ignites most of the fuel as it is introduced into the combustion chamber. This design solves the lower efficiency of typical Otto Cycle engines by allowing the use of a full air charge for each power cycle. This design also solves the problem of heavy duty designs required for existing diesel cycle engines by allowing relatively low compression ratios and therefore lighter weight engine designs. The engine design allows a wide range of fuel combustion properties, as it avoids a dependence on flame propagation through a combustible mixture, where fuel combustion properties control evaporation, rate of flame front propagation and the like. The engine design forces the combustion to be initiated as and at the rate the fuel is introduced into the combustion chamber.

Abstract: A piston for a direct injection engine is provided, the piston having a bowl at an upper end, the bowl forming a portion of a combustion chamber. The bowl includes an inner surface that defines a volume configured to receive a fuel-air mixture, the inner surface of the bowl including a generally concave portion including a flat bottom surrounding a central protruding dome. The relatively flat bottom portion is bounded by two radial concave surface portions which are disposed below two convex separation features for the injected fuel spray. Such surface geometries may reduce soot and improve fuel-air mixing.

Abstract: A four-valve per cylinder engine has two intake valves, two exhaust valves and a centrally located fuel injector. Between each adjacent pair of valves is a valve bridge with a point of minimum separation between adjacent valves. In the present disclosure, the glow plug port is defined in the cylinder top at a location outboard of the minimum separation between adjacent and at a depth which is tangent to an edge of a fuel jet emanating the injector. By placing the glow plug farther outboard than found in the prior art, the glow plug contacts the fuel as it comes out of the injector and as it rebounds off a feature of the piston bowl.

Abstract: A piston is positioned for reciprocal movement in a combustion engine cylinder. Half way between flame plume impingement areas are arranged a first type of protrusions protruding into the combustion chamber and having a smooth form adapted for preserving kinetic energy in a flame plume. Each of the first type of protrusions has a shape of a longitudinal ridge that extends only in the outer bowl area. The first type of protrusions have a left side flank and a right side flank of the ridge when seen from the injector. The left side flank is formed differently compared to the right side flank in order to redirect the movement of a flame plume progressing towards the left side flank in a plane perpendicular to the reciprocal movement, differently compared to corresponding flame plume progressing, towards the right side flank.