Abstract: In a method for operating an internal combustion engine during a catalytic converter heating phase, fuel in at least two portions is injected directly into at least one combustion chamber, a first portion of the fuel being injected during an intake stroke and an injection of a second portion of the fuel taking place directly before an ignition. The second portion is continuously reduced until a freely selectable boundary value of a torque fluctuation has been reached.

Abstract: A high-pressure direct injected gaseous fuel system comprising a fuel tank capable of storing fuel at a first pressure and a compressor including an inlet capable of receiving the fuel, and operative to supply, at an outlet, compressed fuel at a second pressure higher than the first. The system also includes an accumulator connected to the outlet and a plurality of injectors connected to the accumulator. The injectors are adapted to inject fuel directly into a combustion chamber. The system includes a pressure relief valve interconnecting the fuel tank and the outlet, wherein the pressure relief valve is operative to allow fuel flow between the fuel tank and outlet if the second pressure exceeds a threshold pressure.

Abstract: Based on a detection signal of a fuel pressure sensor provided in a first fuel injector, an ECU determines whether a fuel pressure in a first fuel injector is increased over a specified amount when a second fuel injector provided with no fuel pressure sensor terminates a fuel injection. When the ECU determines that the fuel pressure in the first fuel injector is increased over a specified amount, it is diagnosed that the second fuel injector does not have a malfunction of continuous injection.

Abstract: The present disclosure is a method and apparatus for reducing engine emissions utilizing multiple types of fuels. Apparatus for reducing engine emissions may include a controller which may control delivery of a first fuel to be combined with a second fuel at a combustion chamber of an engine. Controller may be configured to provide a proper amount of the first fuel at the correct point in an engine cycle based upon a current engine performance data.

Abstract: A combustion chamber for an opposed-piston engine includes a squish zone defined between circumferential peripheral areas of opposing end surfaces of the pistons, a cavity defined by one or more bowls in the end surfaces, and at least one injection port that extends radially through the squish zone into the cavity. The cavity has a cross-sectional shape that imposes a tumbling motion on air flowing from the squish zone into the cavity. Opposing spray patterns of fuel are injected into the combustion chamber. In some aspects, the opposing spray patterns are injected along a major axis of the combustion chamber.

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: In a method and the corresponding apparatus for operating an internal combustion engine with a plurality of cylinders (Z1 to Z4) which are assigned in each case one injection valve (18) for metering in fuel, a control apparatus (25) is provided with in each case one output stage (25a) for actuating the injection valves (18) of the plurality of cylinders. Here, first of all work injection operations (P0 to P4) are determined for a cylinder (CYL_i) with the duration and positioning in relation to the crankshaft rotary angle. Following this, late injection operations (P5), which are required in certain operating modes, for the preceding cylinder (CYL_i?1) in the ignition sequence are arranged in a setpoint crankshaft angular range (SB) in such a way that no temporal overlaps occur between individual work and late injection operations.

Abstract: A fuel injection system for an internal combustion engine, comprising: at least one fuel electroinjector; and one electronic control unit designed to supply the fuel electroinjector, in a fuel injection phase in an engine cylinder, with at least a first electrical command to perform a pilot fuel injection, and a second electrical command to perform a main fuel injection. The first and second electrical commands are separated in time by an electrical dwell time such that the main fuel injection starts without interruption with respect to the pilot fuel injection. The electrical dwell time between the first and second electrical commands belongs to an electrical dwell time range in which the total fuel amount injected in the pilot and main fuel injections in a fuel injection phase in an engine cylinder is substantially constant.

Abstract: A combustion chamber for an opposed-piston engine includes a squish zone defined between circumferential peripheral areas of opposing end surfaces of the pistons, a cavity defined by one or more bowls in the end surfaces, and at least one injection port that extends radially through the squish zone into the cavity. The cavity has a cross-sectional shape that imposes a tumbling motion on air flowing from the squish zone into the cavity.

Abstract: A system and method for preventing knocking prevents knocking by injecting a sub fuel including ethanol having high octane number to a combustion chamber in a case that the knocking occurs. The system for preventing knocking may include a cylinder, a piston moving in the cylinder reciprocally, forming a combustion chamber with the cylinder, and having a central axis, a first injector mounted at an upper surface of the cylinder with a distance from the central axis of the piston, and directly injecting a main fuel including gasoline into the combustion chamber, a second injector mounted at the upper surface of the cylinder on the central axis of the piston, and directly injecting a sub fuel including ethanol into the combustion chamber, and a spark plug disposed at the upper surface of the cylinder near the second injector.

Abstract: An injector of a diesel engine has a first injection valve and a second injection valve disposed to face each other with respect to the center of a combustion chamber. Assuming that a straight line passing through the first injection valve and the second injection valve is a symmetrical line, one of two regions obtained by dividing a planar region of a combustion chamber (3) into two along the symmetrical line is a first region, and the other of the two regions is a second region, the first injection valve injects fuel toward the first region, and the second injection valve injects fuel toward the second region. A cavity portion is formed in the top surface of a piston. The first injection valve and the second injection valve respectively have injection holes at radially inner positions than the periphery of the cavity portion in plan view.

Abstract: A method of operating an engine comprises introducing into a cylinder volume a non-compression-combustible fuel, such as natural gas, a compression-combustible fuel, such as diesel, and an oxidant and mixing the components for greater than about 275 microseconds, prior to compression combusting the compression-combustible fuel. The mixing may be done such that the two fuels are at least partially homogenized in the cylinder volume. By mixing, or premixing, the two fuels prior to combustion, the compression-combustible fuel is then simultaneously combusted via compression at multiple ignition points in the volume. The second, non-compression-combustible fuel is ignited in response to the combustion of the first fuel. An engine that enables the various methods is also disclosed.

Abstract: A method for controlling an automotive internal combustion engine having direct fuel injection is described, with the method comprising a fuel adaption part in which a fuel quality parameter (F) is determined using a first fuel quality parameter determination procedure when the engine exhibits predetermined operation conditions and a control part which uses the value of the fuel quality parameter (F) or of a fuel combustion characteristics parameter derived from the fuel quality parameter (F) as a target value (?T) in a closed-loop control of the start of injection (SOI) at the engine, with the closed-loop control using a second fuel quality parameter determination procedure being different from the first fuel quality parameter determination procedure to determine an actual value (?A) of the fuel quality parameter (F) or of the fuel combustion characteristics parameter derived from the fuel quality parameter (F).

Abstract: A gaseous fuel engine combines the efficiencies associated with high compression ratio engines with the attractiveness of fueling with natural gas. Each engine cylinder has an associated fuel injector positioned for direct injection and supplied with gaseous fuel from a high pressure common rail. A separate ignition prechamber is also supplied with natural gas and includes an ignition device. Hot gas generated by igniting a mixture of gaseous fuel and air in the prechamber are used to ignite a much larger charge of gaseous fuel injected into the engine cylinder from the fuel injector. The engine has a compression ratio greater than 14: to 1.

Abstract: A dual fuel engine utilizes a compression ignited pilot injection of liquid diesel fuel to ignite a mixture of gaseous fuel and air in each engine cylinder. The gaseous fuel is injected at a relatively low pressure directly into the engine cylinder from a fuel injector. The liquid diesel fuel is injected directly into the engine cylinder from the same fuel injector. In-cylinder dynamic gas blending during the compression stroke can reduce potential hydrocarbon slip that could occur when unburned fuel resides in crevice volumes within the engine cylinder.

Abstract: An internal combustion engine that is structurally similar to a four-stroke engine. The engine comprises at least one cylinder unit, in turn, comprising a cylinder, a piston head that reciprocates within the cylinder, a combustion chamber defined between the cylinder and the front of the piston head, a fuel injector, an oxygen injector, and an exhaust port. The IC engine further comprises a piston rod, one end of which is connected to the piston head and the other end to the crankshaft. The combustion within the combustion chamber is initiated upon the injection of the fuel and the oxygen into the combustion chamber when the piston is at the top dead center. The spent gases are expelled through the exhaust port as the piston returns to the top dead center.

Abstract: Provided is a control device for an in-cylinder injection engine which reduces an amount of fuel attaching and remaining on a piston crown surface so as to bring the first injection as advanced as possible and suppress an increase in the number of exhaust particles of PM, when fuel injection is performed a plurality of times in one cycle in the in-cylinder injection engine. At least the first fuel injection of the respective injections dividedly performed the plurality of times is performed in an intake stroke. At least the first injection start timing of the respective injections dividedly performed the plurality of times is set in accordance with an EGR amount. The first injection start timing is more advanced when the EGR amount is large than when the EGR amount is small.

Abstract: A fuel injection apparatus includes: an adsorbent disposed in an internal space of a leading end portion of a fuel injector, the adsorbent being capable of selectively adsorbing an alcohol component in the blended fuel of gasoline and alcohol; fuel pressure controller capable of achieving states in which a pressure of fuel to be supplied to the fuel injector is set to a low or high pressure range having a small or large adsorbed amount of alcohol on the adsorbent; and split injection controller that makes the fuel injector inject fuel for one cycle in a plurality of times, when the pressure of fuel to be supplied to the fuel injector is set to the high pressure range.

Abstract: Methods and systems are provided for improving fuel usage while addressing knock by adjusting the use of spark retard and direct injection of a fluid based on engine operating conditions and the composition of the injected fluid. One or more engine parameters, such as EGR, VCT, boost, throttle position, are coordinated with the direct injection to reduce torque and EGR transients.

Abstract: A method for controlling a direct-injection fuel injector for an internal combustion engine includes identifying linear and non-linear fuel mass delivery regions corresponding to predefined ranges of injection duration, monitoring an operator torque request, determining a total desired fuel mass associated with the operator torque request, identifying a fuel mass delivery region corresponding to the total desired fuel mass, and commanding a plurality of partial injection events having injection durations corresponding to the linear fuel mass delivery region to inject the total desired fuel mass when the total desired fuel mass corresponds to the non-linear fuel mass delivery region.

Abstract: Systems and methods for operating an engine include controlling a temperature of recirculated exhaust gas to achieve a predetermined recirculated exhaust gas temperature. A mixture of air and temperature-controlled recirculated exhaust gas are admitted in a combustion chamber and a gaseous fuel injector delivers gaseous fuel during an intake stroke. A diesel fuel injector is activated for a first time to deliver a pre-pilot diesel quantity directly into the combustion chamber at an early stage of a compression stroke, and is activated again for a second time to deliver a pilot diesel quantity directly into the combustion chamber at a later stage of the compression stroke. A total air/fuel ratio within the combustion chamber upon completion of the second diesel fuel injector activation is lean. The air/fuel mixture is combusted during a combustion stroke, and combustion products are removed during an exhaust stroke.

Abstract: A control system of an internal combustion engine provided with a first fuel injection valve that injects fuel into a cylinder of the internal combustion engine, a second fuel injection valve that injects fuel into an intake port of the internal combustion engine, an EGR passage that introduces an EGR gas from an exhaust passage of the internal combustion engine to an intake passage thereof, an EGR valve that is arranged in the EGR passage, and an obtaining unit that obtains an amount of intake air in the internal combustion engine. When the EGR valve is open, a determination is made as to whether the amount of intake air is in an increasing tendency or in a decreasing tendency with respect to a change in the cylinder injection ratio, and a value of the amount of intake air thus obtained is corrected based on the determination.

Abstract: A control apparatus for a direct injection type engine is provided for reducing an amount of fuel that adheres to and that remains on a crown surface of a piston so as to suppress the increase of Number of particles as well as advancing the first injection as much as possible when plural fuel injections are carried out in one cycle in the direct injection type engine. The first injection timing is set based on a pulse width of at least the first injection among each of injections split plural times, and when the pulse width of the split first injection is short, the injection timing of the first injection is more advanced as compared with a case of a longer pulse width of the split first injection.

Abstract: A method is provided for operating a direct injection system of an internal combustion engine of a motor vehicle. The at least one fuel injection parameter is adjusted by a closed loop control of the injected fuel quantity.

Abstract: A dual fuel injector utilizes first and second control valves to open and close first and second nozzle outlet sets to inject a first fuel and a second fuel, respectively. The first and second control valves have concentric lines of action, and include a self alignment feature with respect to a flat seat. The two fuels may differ in at least one of chemical identity, matter phase and pressure.

Abstract: A dual fuel injection valve with concentric needles comprises an inner needle and an outer needle surrounding the inner needle, both needles being located inside the injection valve body. The valve is provided with a first set and a second set of orifices for separately injecting two different fuels directly into the combustion chamber of an internal combustion engine. The outer needle is fixed against rotation with respect to the injection valve body such that an interlace angle between the centerlines of the first series of orifices and second series of orifices is set at different predetermined angles to reduce methane emissions.

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: A compression ignition dual fuel engine supplies natural gas fuel and liquid diesel fuel to each engine cylinder from a common fuel injector. Each fuel injector is fluidly connected to both a liquid fuel common rail and a gaseous fuel common rail. The engine includes a surplus gas system for capturing surplus gas, such as evaporated gas from the gaseous fuel supply and pressure control system, or left over pressurized natural gas produced by engine shut down. Rather than being vented to atmosphere, the surplus gas can be burned in the engine when operating conditions present burn opportunities.

Abstract: A method for the operation of homogeneous charge compression ignition engines (HCCI) using gasoline or similar single-stage ignition fuels. Partial fuel stratification (PFS), intake pressure boosting and controlled BDC-intake temperatures, typically in the range of 95° C. to about 125° C., are used to reduce combustion pressure rise rates (PRR), and therefore, the knocking propensity of homogeneous charge compression ignition engines operating on gasoline or similar fuels.

Abstract: The present invention relates to a fuel injection control apparatus for controlling fuel injection and a method therefor in an engine having first and second intake passages provided with first and second fuel injection valves, respectively. Fuel injection modes using the two injection valves include an alternative injection mode in which the first and second fuel injection valves are alternately operated every predetermined number of cycles and a combined injection mode in which both the first and second fuel injection valves are used for each cycle. Then, the combined injection mode is selected in a full load range. In a partial load range, the alternative injection mode is selected in a cold state and the combined injection mode is selected after warm-up. Accordingly, it is possible to reduce an equilibrium amount of adhering fuel to an inner wall of an intake passage.

Abstract: A diesel engine is provided, which includes an engine body to be supplied with fuel containing diesel fuel as its main component, a geometric compression ratio being set to 15:1 or below, a fuel injection valve arranged in the engine body so as to be oriented toward a cylinder of the engine body and for directly injecting the fuel into the cylinder, and a control module for controlling a mode of injecting the fuel into the cylinder through the fuel injection valve. The control module performs a main injection where the fuel is injected to cause a main combustion mainly including a diffusion combustion and performs a plurality of pre-stage injections where the fuel is injected prior to the main injection to cause a pre-stage combustion prior to the main combustion. The control module controls the injection mode of the injections to adjust a heat release rate.

Abstract: A method is provided for regenerating a diesel particulate filter within a diesel engine system that includes, but is not limited to at least a combustion chamber defined by a reciprocating piston inside a cylinder, at least an exhaust valve for cyclically open the combustion chamber towards an exhaust line, and the diesel particulate filter located in the exhaust line, wherein the method comprises injecting an amount of fuel into the combustion chamber by means of least two consecutive after-injection pulses (AIP1-AIP3), each of which starts (SOI) after the piston has passed the top dead center (TDC), and sufficiently near to the latter for the fuel to burn at least partially inside the combustion chamber.

Abstract: This disclosure provides a control device for a diesel engine. When the engine is within a particular operating range with a low engine speed and a partial engine load and in a low temperature state where a cylinder temperature at a compression stroke end is lower than a predetermined temperature, a forced induction system sets a forcibly inducting level higher than a predetermined level that is higher than that in a high temperature state where the cylinder temperature is above the predetermined temperature. At least within the particular operating range, an injection control module performs a main injection where a fuel injection starts at or before a top dead center of the compression stroke to cause main combustion mainly including diffusion combustion and performs a pre-stage injection where the fuel injection is performed at least once prior to the main injection to cause pre-stage combustion before the main combustion starts.

Abstract: The present description relates to operation and control of a fuel reformer. In one embodiment, an engine constituent is adjusted in response to limiting an amount of reformate supplied to the engine during a condition of reformer degradation. The approach can improve engine operation. In this way, consequences of reformate system degradation may be reduced by limiting use of the reformate system after degradation is detected.

Abstract: The disclosure provides a control device of a spark-ignition gasoline engine. When an operating state of an engine body is within a low engine speed range, a controller operates a fuel pressure variable mechanism so that a fuel pressure is higher within a high engine load range compared to a low engine load range, the controller operates, within the high engine load range, a fuel injection mechanism to perform at least a fuel injection into the cylinder by a cylinder internal injection valve at a timing during a retard period from a late stage of a compression stroke to an early stage of an expansion stroke, and the controller operates, within the high engine load range, an ignition plug to ignite at a timing during the retard period and after the fuel injection.

Abstract: A fuel-pressure waveform detector has a detect-waveform obtaining unit for obtaining a multi-stage injection pressure waveform by means of a fuel-pressure sensor while performing a multi-stage fuel injection during one combustion cycle. A model waveform memory stores a reference model pressure waveform of when a single fuel injection is performed. A waveform extracting unit extracts a pressure waveform due to the subject fuel injection by subtracting the reference model pressure waveform from the multi-stage injection pressure waveform. A correction unit corrects the reference model pressure waveform in such a manner that its attenuation degree becomes larger as a fuel injection period of the subject fuel injection is longer.

Abstract: A surge tank 52 is placed above an engine main body 4. Plural intake runners 51 include curved portions 51C, respectively, which are placed on one side of the engine main body 4, and sloped portions 51D extending from the surge tank 52 to the curved portions 51C. An air cleaner 7 is placed above the sloped portions 51D. A liquid fuel injection unit 8 is placed in a space between the engine main body 4 and the intake runners 51. A gaseous fuel injection unit 11 is placed in a gap between the surge tank 52 and the air cleaner 7. Gaseous fuel injection valves 103 are held by a bracket on a gaseous fuel delivery pipe 10A in a way that they are placed under the air cleaner, each of them being placed in a space between the adjacent two of the sloped portions 51D.

Abstract: In an internal combustion engine 20 that promotes combustion of fuel injected from an injector 50 to a combustion chamber 21 by way of electromagnetic wave plasma, a plurality of pieces of the electromagnetic wave plasma are generated respectively for a plurality of jet flows inlected from the injector 50. A plurality of antennae 36 are provided respectively for a plurality of injection holes of the injector 50. Each antenna 36 is disposed on an exposed surface 46a of a piston 46 exposed to the combustion chamber 21 at a location corresponding to each injection hole 55. While the injector 50 injects fuel, each antenna 36 emits the electromagnetic wave to the combustion chamber 21, thereby generating the electromagnetic wave, plasma.

Abstract: A method provides for detecting deviations of injection quantities for injections into internal combustion engines, as carried out for example by common-rail systems. At least one deviation of at least one injection quantity is detected by determining at least one deviation, from a predefined value in each case, of at least one value of at least one variable controlling an actuator of the injector and/or indicating at least one state of the actuator.

Abstract: A direct fuel-injection engine includes a piston, a cavity recessed in a central part of a top face of the piston, and a fuel injector. At a main injection collision point of a fuel-injection axis when main injection is performed while the piston is near top dead center, a main injection collision angle formed between its tangent and the fuel-injection axis is set at an obtuse angle. Fuel colliding with the main injection collision point is deflected towards a cavity open end side. At a secondary injection collision point of the fuel-injection axis when performing secondary injection with the piston is further from top dead center, a secondary injection collision angle formed between its tangent and the fuel-injection axis is set at one of a right angle and an acute angle. Fuel colliding with the secondary injection collision point is deflected primarily in the circumferential direction of the cavity.

Abstract: A fuel supply apparatus for an internal combustion engine having a plurality of cylinders, which supplies fuel through fuel injection valves provided corresponding to the plurality of cylinders. An amount of fuel supplied to the engine is controlled by changing a fuel injection period of said fuel injection valve, and performing a fuel injection with a plurality of injection modes including a reference injection mode. A fuel injection amount parameter for controlling a valve opening period of the fuel injection valve in the reference injection mode, is calculated according to an operating condition of said engine.

Abstract: An automobile-mount diesel engine with a turbocharger is provided, which includes an engine body with the turbocharger, the engine body being mounted in the automobile and supplied with fuel containing diesel fuel as its main component, a fuel injection valve arranged in the engine body so as to be oriented toward a cylinder of the engine body and for directly injecting the fuel into the cylinder, an injection control module for controlling a mode of injecting the fuel into the cylinder through the fuel injection valve, and an EGR amount control module for adjusting an amount of EGR gas introduced into the cylinder. EGR and fuel injection are adjusted based on speed-load conditions of the engine.

Abstract: A fuel injection control apparatus of an internal combustion engine of the present invention performs control for a common rail diesel engine so that at a timing when a piston reaches compression top dead center, the rate of heat production due to the combustion of fuel injected in pre-injection is substantially maximal, and furthermore so that the combustion of fuel injected in main injection is started in the vicinity of this timing. As a result, the combustion of fuel injected in main injection is started by fully utilizing the heat production amount due to the pre-injection. Also, this avoids the production of reverse torque, as well as ensures maximizing the amount of torque produced by the combustion of fuel injected in main injection.

Abstract: Increase in combustion noise and deterioration of exhaust gas performance caused by inter-cylinder correction are prevented, and decrease in temperature rise performance of a diesel particulate removal device caused by inter-cylinder correction is prevented.

Abstract: A passive hydraulically actuated non-electric shutdown pressure relief valve relieves pressure in the high pressure volume of a low static leak common rail fuel system after shutdown. When the common rail fuel system is in operation, a transfer pump provides medium pressure to hold the shutdown pressure relief valve closed. At shutdown, the residual medium pressure downstream from the transfer pump decays back to tank, and the residual high pressure trapped in the common rail and fuel injectors pushes open the shutdown pressure relief valve to release the high pressure after back to tank.

Abstract: A compression ignition gasoline engine uses low-cetane number fuel, such as gasoline. The engine includes a combustion control device having an injector directly injecting fuel into a combustion chamber, intake and exhaust valves, and a variable valve device changing a valve timing, in which the compression ignition gasoline engine includes: at least two intake valves and two exhaust valves; a spark plug positioned at the center portion of the combustion chamber; and an injector positioned adjacent to the spark plug toward the center portion of the combustion chamber, in which the exhaust valve is a symmetric valve lift in which the lift and the opening section of the tow exhaust valves are the same in low lift, and the intake valve is an asymmetric valve lift in which the lift and the opening of the two intake valves are different in the low lift.

Abstract: A method of operating a combustion ignition engine comprises introducing an amount of a compressibly non-ignitable fuel into the air induction system of a compression ignition engine during the intake stroke of the engine and then injecting an amount of compressibly ignitable fuel (e.g., Diesel fuel) in the cylinder chamber at a crank angle sufficiently advanced during the compression stroke of the compression ignition engine such that the compressibly ignitable fuel and incompressible non-ignitable fuel ignite and combust such that substantially all of the fuel in the cylinder is combusted, where the amount of compressibly non-ignitable fuel introduced into the cylinder has an energy content that is at least about 50% to at most about 99% of the total energy content of the total amount of fuel introduced.

Abstract: A system, method and apparatus for monitoring the performance of a gas turbine engine. A counter value indicative of the comparison between the engine condition and the threshold condition is adjusted. The aircraft operator is warned of an impending maintenance condition based on the counter value and determines an appropriate course of action.

Abstract: Methods and systems are provided for controlling exhaust emissions by adjusting a fuel injection into an engine cylinder from a plurality of fuel injectors based on the fuel type of the injected fuel and further based on the soot load of the engine. Soot generated from direct fuel injection is reduced by decreasing an amount of direct injection into a cylinder as the engine soot load increases.

Abstract: In a gaseous-fuelled stoichiometric compression ignition internal combustion engine, a pilot fuel is injected directly into the combustion chamber to help initiate a multi-point ignition. The engine provides performance improvements approaching those of high pressure direct injection engines but with less complexity because the gaseous fuel is introduced into the intake air subsystem at relatively low pressure and as a result of the stoichiometric combustion, the low oxygen content in the combustion products exiting the combustion chamber allows the use of a three-way catalyst instead of other after treatment arrangements normally associated with conventional compression ignition engines that require the addition of a reductant.