Abstract: The present invention relates to a rotary engine comprising a stator, a first rotor rotatably mounted on the stator about a rotational axis of the first rotor, and a second rotor rotatably mounted on the stator about a rotational axis of the second rotor parallel to the rotational axis of the first rotor such that the second rotor is eccentrically mounted to and surrounding the first rotor, wherein the first rotor comprises a first cylinder with a piston chamber limited by a translationally displaceable first piston with a first rod fixed to an outer side of the second rotor on an end of the first rod outwardly projecting from the first cylinder towards the outer side of the second rotor and fixed to the first piston on the other end of the first rod, wherein the first rotor further comprises at least one second cylinder, each of the at least one second cylinder comprising a piston chamber limited by a translationally displaceable second piston with a second rod coupled to an outer side of the second rotor on

Abstract: A positive displacement expander with an operating fluid chamber of expansive volume regulated by a shifting head. The shifting head may enhance rotation of a housing utilized to rotate a shaft for providing work to any of a variety of power retrieval devices. Additional efficiencies may also be realized through unique hydraulic layouts for circulating of the operating fluid from a heat exchanger, through the rotary device and to a cold exchanger for continuous operating of the rotary device.

Abstract: An engine comprises a housing and a combustion assembly carried by the housing. The combustion assembly comprises an annular bore defined by the housing, at least one combustion piston disposed within the annular bore, and a sealing mechanism configured to selectively seal the at least one combustion piston relative to at least one corresponding wall of the annular bore. The engine comprises at least one rotary valve configured to move between a first position within the annular bore to allow the at least one combustion piston to travel within the annular bore from a first location proximate to the at least one valve to a second location distal to the at least one rotary valve and a second position within the annular bore to define a combustion chamber relative to the at least one combustion piston at the second location.

Abstract: Systems and methods for a heat engine system are described. In one embodiment, a system comprises a heat engine compressor, a heat exchanger, and a heat engine expander. The system comprises a partial state condenser in fluid communication with the heat engine expander. The partial state condenser includes a sense reservoir to hold the working fluid, a reservoir sensor to sense an electrical property of the working fluid, and a reservoir valve. The reservoir valve is in fluid communication with the sense reservoir, the heat engine compressor, and a heat engine condenser. The system comprises a processor to execute instructions to determine a specific energy of working fluid based on the electrical property of the working fluid and control the reservoir valve based on the specific energy to maintain a two-phase saturated state point within the partial state condenser based on the electrical property.

Abstract: A control system is provided for a turbine valve. The turbine valve has a first coil and a second coil to control or sense movement of a mechanical valve positioner. Two valve positioners are provided with each valve positioner having two drive circuits to drive the first and second coils. Switches are provided such that only one drive circuit is connected to each coil at a time. The control system may also include a hydraulic pilot valve section and a main hydraulic valve section. Feedbacks are used to determine a pilot valve error and a main valve error which are combined to determine a turbine valve error. The turbine valve error is repeatedly determined to minimize the error.

Abstract: A turbomachine blade, and a coupon for a turbomachine blade, are disclosed. The blade may include an airfoil body having a pressure side and a suction side connected by a leading edge and a trailing edge, a coolant feed passage defined in the airfoil body, and a coolant reuse passage defined in the airfoil body. The blade may also include a first cooling circuit defined in the airfoil body. The first cooling circuit may include a rearward passage extending toward the trailing edge from and fluidly coupled to the coolant feed passage, and a radially spreading return passage extending away from the trailing edge toward and fluidly coupled to the coolant reuse passage. The cooling circuit may also include a radially extending turn passage coupling the rearward passage and the radially spreading return passage. A first set of obstructions may be positioned in the radially extending turn passage.

Abstract: A retention ring for a gas turbine engine according to an example of the present disclosure includes, among other things, a main body extending in a circumferential direction about an axis to establish a continuous hoop having a first diameter and a second diameter. The main body includes first and second circumferential faces along opposite sides of the main body. The first circumferential face is dimensioned to abut a gas turbine engine component. The main body includes at least one removal feature dimensioned to sever in response to engagement with a cutting tool. A method of assembly is also disclosed.

Abstract: A turbine for a turbomachine has a first rotor and a second rotor configured to pivot about an axis in two opposite directions of rotation. The first rotor includes a radially outer drum from which blades extend radially inwards. The turbine has cooling means attached relative to the outer drum. The cooling means include a support plate with at least one first orifice and a calibration plate that is attached to the support plate and located radially inside the support plate. The calibration plate has at least one second calibration orifice facing the outer drum to allow the passage of cooling air radially from the outside to the inside through the first and second orifices.

Abstract: A gas turbine engine according to an example of the present disclosure may include, among other things, a fan section including a fan having a plurality of fan blades and including an outer housing surrounding the fan blades to establish a bypass duct, a geared architecture, a first spool including a first shaft that interconnects a first compressor and a fan drive turbine, the fan drive turbine driving the fan through the geared architecture. The gas turbine engine is rated to provide an amount of thrust at ground idle, and the gas turbine engine is rated to provide an amount of thrust at maximum takeoff. A thrust ratio is defined as a ratio of the amount of thrust at ground idle divided by the amount of thrust at maximum takeoff. The thrust ratio can be less than or equal to 0.050.

Abstract: An aircraft engine, has: a low-pressure compressor and a high-pressure compressor located downstream of the low-pressure compressor; a gaspath valve upstream of the high-pressure compressor, the gaspath valve movable between an open configuration and a closed configuration; and a bypass flow path having in flow series a bypass inlet, a bypass valve, and a bypass outlet, the bypass inlet fluidly communicating with the gaspath upstream of at least one stage of the low-pressure compressor, the bypass valve having an open configuration in which the bypass valve allows a bypass flow and a closed configuration in which the bypass valve blocks the bypass flow, the bypass outlet fluidly communicating with the bypass inlet via the bypass valve and with the gaspath at a location in the gaspath fluidly downstream of the gaspath valve, downstream of the low-pressure compressor, and upstream of the high-pressure compressor.

Abstract: Methods and systems for measuring an axial position of a rotating component of an engine are described herein. The method comprises obtaining a signal from a sensor coupled to the rotating component, the rotating component having a plurality of position markers distributed about a surface thereof, the position markers having an axially varying characteristic configured to cause a change in a varying parameter of the signal as a function of the axial position of the rotating component. Based on the signal, the method comprises determining a rotational speed of the rotating component from the signal, determining the varying parameter of the signal, and finding the axial position of the rotating component based on a known relationship between the axial position, the rotational speed, and the varying parameter of the signal.

Abstract: A method of optimizing probe placement in a turbomachine is disclosed which includes establishing a design matrix A of size m×(2N+1) utilized in developing flow properties around an annulus of a turbomachine, where m represents the number of datapoints at different circumferential locations around the annulus, and N represents dominant wavelets generated by upstream and downstream stators and blade row interactions formed around an annulus, wherein m is greater or equal to 2N+1, and optimizing probe positioning by iteratively modifying probe positions placed around the annulus and for each iteration determining a condition number of the design matrix A for each set of probe positions until a predetermined threshold is achieved for the condition number representing an optimal probe layout.

Abstract: A system comprises a gas turbine engine including a compressor, combustor, gas turbine, the combustor including a plurality of late lean fuel injectors; and wash system configured to be attached to and in fluid communication with the a plurality of late lean fuel injectors of the combustor. The wash system includes a water source supplying water; a first fluid source supplying a first fluid; a mixing chamber in communication with the water source and first fluid source; a water pump to pump water to the mixing chamber; a first fluid pump to pump the first fluid to the mixing chamber; a fluid line in fluid communication with the mixing chamber and at least one of the plurality of late lean fuel injectors so fluid from the mixing chamber is injected into the combustor at late lean fuel injectors. The wash system is operated with the gas turbine engine off-line.

Abstract: Methods, apparatus, systems, and articles of manufacture to provide damping of an airfoil are disclosed. An example airfoil is disposed in a flow path, the airfoil including a shell defining an exterior surface of the airfoil and forming a cavity in an interior surface of the airfoil, and a lattice damper disposed in the cavity, the lattice damper to reduce vibrational loads exerted on the airfoil.

Abstract: A tip shroud, comprising a plurality of tip shoes encircling a rotor assembly, in a turbine may deform due to thermal gradients experienced during operation of the turbine. Accordingly, a tip shoe is disclosed that utilizes an internal cooling cavity to supply coolant throughout the interior of the tip shoe, as well as to the slash faces of the tip shoe. In addition, features are described that increase the surface area exposed to the coolant, while remaining suitable for additive manufacturing.

Abstract: An apparatus is provided for a turbine engine. This turbine engine apparatus includes a journal bearing extending axially along and circumferentially about an axis. The journal bearing extends radially between a bearing inner side and a bearing outer side. The journal bearing includes a bore, a passage, a groove and a slot. The bore extends axially within the journal bearing and along the bearing inner side. The passage extends radially within the journal bearing and is fluidly coupled with the bore and the groove. The groove extends longitudinally within the journal bearing at the bearing outer side between a groove first end and a groove second end. At least a portion of the slot extends circumferentially about the axis within the journal bearing at the bearing outer side from the groove first end to the groove second end.

Abstract: A gas turbine engine has a fan drive turbine for driving a gear reduction. The gear reduction drives a fan rotor. A lubrication system supplies oil to the gear reduction, and includes a lubricant pump to supply an air/oil mixture to an inlet of a deaerator. The deaerator includes a separator for separating oil and air, delivering separated air to an air outlet, and delivering separated oil back into an oil tank. The separated oil is first delivered into a pipe outwardly of the oil tank, and then into a location beneath a minimum oil level in the tank. Air within the oil tank moves outwardly through an air exit into the deaerator. A method of designing a gas turbine engine is also disclosed.

Abstract: A flange arrangement of a gas turbine engine includes a first flange of a first component, and a second flange of a second component axially offset from the first flange along an engine central longitudinal axis. The first flange is secured to the second flange. One or more flange flowpaths are defined between the first flange and the second flange to convey a flange airflow from an interior of the second component thereby thermally conditioning the flange arrangement. The flange airflow is driven through the one or more flange flowpaths by a pressure differential.

Abstract: A mounting system for supporting rotating machinery is described. The system comprises a base frame having an upper side for mounting the rotating machinery, and a lower side. A set of main supporting members are arranged according to a triangular arrangement and forming a three-point mounting arrangement defining a mounting plane. Moreover, a set of auxiliary supporting members, having a variable stiffness in at least one direction, are provided and are configured and arranged such as to increase the stiffness thereof when the base frame is subject to an overload, thus reducing load on the main supporting members.

Abstract: A method of repairing a tip for an airfoil is disclosed herein. In various embodiments, the method comprises: removing a portion of the airfoil that reduces a radial height of the airfoil and at least partially removes a defect of the airfoil; removing a remainder of the defect; joining, via gas tungsten arc welding, a filler material to the airfoil to repair the defect; and joining a first mating surface of the airfoil to a second mating surface of a blade tip body via a solid-state joining process.

Abstract: A bladed disc system for a turbine engine having a disk portion and a plurality of blade portions which are associated with a stator section and an intercavity sealing portion, disc portion shaped such that blade portions are able to fit within firtree slot in disc portion, blade portion having aerofoil section and root section, aerofoil section having portion shaped such that they extend proximate to intercavity sealing portion, disc portion extending from portion that connects with drum to outer edge at which blade portions are connected with disc portion having width transition region in which thickness of disc increases from point at which disc connects to drum to outer edge at which it holds blade portions, and wherein width transition region has curved width transition region with radius r, and an overhanging portion which extends into the intercavity spacing between the width transition region and the intercavity sealing portion.

Abstract: A rotor blade 32 includes a blade body 33 which has a negative-pressure surface 33a and a positive-pressure surface 33b extending in a blade height direction Z, and a platform 35 which is connected to an end portion of the blade body 33 in the blade height direction Z and extends in a circumferential direction Dc. In an end surface 35a of the platform 35 facing an axial direction Da, a convex portion 51 protruding in the axial direction Da and a concave portion 52 recessed in the axial direction Da are formed on an end surface 35a of the platform 35 facing the upstream side Dau. When viewed in the blade height direction Z, the convex portion 51 and the concave portion 52 are alternately formed in the circumferential direction Dc.

Abstract: A rotor vane for an aircraft turbine engine includes a blade extending between an inner platform and an outer platform which carries at least one projecting lip. The blade has a lower surface and an upper surface, and the outer platform includes, on the side of the lower and upper surfaces, lateral edges configured to cooperate in a form-fitting manner with complementary lateral edges of adjacent vanes. Each of the lateral edges has an anti-wear coating, and one of the lateral edges forms a hollow tip (P) with a bowl configured to receive the coating and further including a first concave cylindrical surface portion, the geometric dimensions of which are optimized to limit the risk of cracks appearing when the coating is applied.

Abstract: A method for stripping a coating off of a blade includes discharging liquid nitrogen through a nozzle onto the blade at a coating to cause lifting of the coating from a substrate of the blade and traversing the nozzle along the blade to cause peeling of the coating off of the substrate of the blade as the nozzle traverses the blade.

Abstract: A rotor has formed therein a groove with which a moving blade including a dovetail portion and a platform portion connecting the dovetail portion and a blade portion engages. The groove opens in a surface intersecting the axis of rotation of the rotor, and includes a contacting portion extending obliquely with respect to the axis of rotation and coming into contact with the dovetail portion, a bottom portion of an end portion on the radially inner side of the rotor, a joining portion between the contacting portion and the bottom portion, a platform facing portion facing the platform portion, and a chamfered portion formed on an end surface in the groove-extending direction. The chamfered dimension of the joining portion is greater on the side with an acute angle between the groove and the end surface than on the side with an obtuse angle between the groove and the end surface.

Abstract: Disclosed herein are a grooved turbine blade, and a turbine and a gas turbine including the same. According to the disclosure, since a groove part is formed on a root member to disperse torsional stress, it is possible to improve durability of a rotor disk to which the turbine blade is assembled.

Abstract: One of spacing between the base-side first tooth and the base-side second tooth or spacing between the base-side second tooth and the base-side third tooth is greater than spacing between the tip-side first tooth and the tip-side second tooth.

Abstract: The invention relates to a straightening assembly (28) comprising two radially inner and outer coaxial shells (34) between which extend vanes (36) made of composite material, fixed to a first end portion on the radially inner shell and to a second end portion on the radially outer shell, characterized in that: for each vane (36), in a plane perpendicular to the axis of the radially inner and outer shells (34), a straight line passing through a junction between said first and second end portions and the useful part forms an angle ? with a radius of the radially inner shell, passing through the junction between said first end portion and the useful part of said vane (36), such that 0°<??30°; the radially inner shell has a diameter ranging from 1,000 mm to 1,600 mm; and in that the radially outer shell has a diameter ranging from 2,000 to 2,800 mm; the number of vanes (36) ranges from twenty-five to forty-five.

Abstract: A turbomachine defining a flowpath therethrough at which a fluid is compressed is provided, in which the turbomachine includes a first compressor in serial flow arrangement upstream of a second compressor. The second compressor includes a port at the flowpath and is configured to receive at least a portion of the fluid from the flowpath from the second compressor. The first compressor includes a vane positioned at the flowpath and the vane includes an opening at the flowpath configured to egress the portion of the fluid from the port into the flowpath.

Abstract: An apparatus is provided for a gas turbine engine. This gas turbine engine apparatus includes a first platform, a second platform, a plurality of vanes and a plurality of beams. The first platform extends axially along and circumferentially about an axis. The second platform extends axially along and circumferentially about the axis. The vanes are arranged circumferentially about the axis. Each of the vanes extends radially across a gas path between the first platform and the second platform. The vanes include a first vane movably connected to the first platform. The beams are arranged circumferentially about the axis. The beams are fixedly connected to the first platform and the second platform. The beams include a first beam extending radially through the first vane.

Abstract: A turbine comprises a casing, an outer metal shroud, an inner metal shroud and an annular distributor having a plurality of CMC ring sectors, each sector comprising a mast, an inner platform, an outer platform and at least one blade having a hollow profile that defines an inner housing, the inner and outer platforms each having an opening communicating with said inner housing, and the mast passing through said openings and the inner housing and being secured to said casing and connected to said annular sector. Each blade comprises at least one first radial shoulder projecting axially towards the inside of the blade, and each mast comprises at least one second shoulder projecting axially towards the outside of the mast configured to radially cooperate with a first shoulder and radially press the blade against the mast.

Abstract: A turbine nozzle assembly includes at least one airfoil and an outer endwall coupled to a radial outer end of the at least one airfoil. A mounting rail is coupled to the outer endwall and extends at least partially radially outward from the outer endwall and at least partially circumferentially along the outer endwall. A stress relief structure is defined in the mounting rail. The stress relief structure includes an end opening defined in a radial outer surface of the mounting rail, a slot defined through the rail thickness of the mounting rail and coupled to the end opening, and an oblong opening defined through the rail thickness of the mounting rail and coupled to a radial inner end of the slot. The oblong opening is arranged asymmetrically in a circumferential direction relative to the slot to relieve stress where prevalent in the mounting rail.

Abstract: A system and method for heating steam sample and chemical sample and feed tubes/lines in a natural gas fired heat recovery steam generator (HRSG) power plant including a tube impedance heater (IH) control system and at least one impedance heated tube having an outer insulation and an electrically conducting inner tube member, the impedance heated tube having an input IH feed power electrical connector and electrically connected at a first connection to the inner tube member, and a return IH power electrical connector electrically connected at a second connection by a first end of a return electrical cable and a first connector and second connector each mechanically and fluidly coupling the first and second connections respectively to the inner tube member to the steam sample or chemical sample or feed tube/line and electrically isolating the first end and second ends.

Abstract: A method for checking the oil level in a marine drive unit, where the drive unit is provided with an external oil filter, an oil level sensor adapted to determine an oil level in the drive unit, and an electronically controlled tilt means, comprising the steps of, initiating an oil level check, controlling the tilt means to tilt the drive unit to a plurality of different tilt angle positions, for each tilt angle position, determining if the oil level sensor detects the oil level in the drive unit, for each tilt angle position, registering the tilt angle of the drive unit and the signal from the oil level sensor, determining at which tilt angles the sensor detects the oil level, and in dependence of the determined tilt angle of the drive unit, determining if the oil level of the drive unit is within a predefined range.

Abstract: A component of an exhaust system for an internal combustion engine comprises a wall in which at least one opening is provided. A perforated cover at least partly closes the at least one opening. The perforated cover is mounted on the wall using a holder, and a portion of the perforated cover engages into an opening provided on the holder. There is also presented an exhaust system comprising such a component, and a method for manufacturing such a component, in which the perforated cover is mounted on the holder by introducing at least one portion of the perforated cover into an opening provided on the holder.

Abstract: A recycling loop configuration of an exhaust gas aftertreatment system decreases a level of system-out NOx emissions of an engine. An apparatus including the configuration has an exhaust gas recycling system having a closed gas recycling loop system configured to heat gas circulating within the loop, and a blower for circulating gas within the loop. A method for operating the engine includes preheating at least one aftertreatment component of an exhaust gas aftertreatment system of the engine by exposing the component to heated gas circulating in a closed gas recycling loop.

Abstract: A method (200) for operating an exhaust-gas catalytic converter (130) with central coordination of heating measures that are intended to heat the exhaust-gas catalytic converter (130) to a temperature level at which the reactions to be catalyzed take place with an adequate reaction rate (so-called catalytic converter window). Through the central coordination of the heating measures on the basis of defined heating strategies, in which in each case one or more of the available heating measures are combined with one another in an expedient manner, the required outlay in terms of control can be considerably reduced, and mutual interference of the heating measures can be avoided.

Abstract: A method for operating an exhaust-gas purification system which is arranged in the exhaust system of an internal combustion engine, and an exhaust-gas purification system, are described. In the method, a combination of electrical catalytic converter heating measures with internal combustion engine catalytic converter heating measures is implemented, whereby particularly fast and inexpensive heating of a catalytic converter is achieved. The corresponding exhaust system preferably has, in an exhaust-gas flow direction, firstly a support catalytic converter and then a heated catalytic converter.

Abstract: An aftertreatment system connected downstream an internal combustion engine arrangement for receiving exhaust gases conveyed from the internal combustion engine arrangement during operation thereof, wherein the aftertreatment system comprises first and second catalytic devices in series, wherein a gap is there between.

Abstract: The present invention relates to a mixing apparatus for introducing and distributing a liquid additive into a gas flow, in particular for an exhaust gas system of an internal combustion engine. The mixing apparatus comprises a gas-guiding section for guiding the gas flow and a metering-in device for introducing the additive into a metering-in region of the gas-guiding section. Furthermore, a heating device for actively heating at least one heating section of the gas-guiding section is provided. The heating section is arranged in the metering-in region and/or downstream of the metering-in region. The gas-guiding section has, in the heating section, at least one elevated portion projecting radially into the gas flow for influencing the flow of the gas flow and thus the preparation of the additive.

Abstract: A method of treating exhaust gas from an internal combustion engine as the exhaust gas passes through an exhaust gas pathway includes injecting reductant into the exhaust gas pathway with a reductant injector, filtering particulate matter from the exhaust gas with a first treatment element located downstream of the reductant injector, oxidizing soot on the first treatment element with ozone, and converting nitrogen oxides (NOx) from the exhaust gas with a second treatment element located downstream of the reductant injector.

Abstract: A gas turbine engine includes a fan shaft diving a fan having fan blades. A gear system includes a sun gear surrounded by a plurality of intermediate gears. A carrier at least partially supports the plurality of intermediate gears. A ring gear surrounds the plurality of intermediate gears. The sun gear is driven by a turbine. At least one fan shaft support bearing is located forward of the gear system. A coupling fixes the ring gear from rotation relative to an engine static structure. A lubrication system lubricates components across a rotation gap. The lubrication system includes a lubricant input. A stationary first bearing receives lubricant from the lubricant input and has a first race in which lubricant flows. A second bearing rotates within the first bearing. The second bearing has a first opening in registration with the first race such that lubricant may flow from the first race through the first opening into a first conduit.

Abstract: Methods and systems are provided for model-based determination of a temperature distribution of an exhaust aftertreatment system of a vehicle. A power demand from a first component of the aftertreatment system is measure, a heat transfer into the first component of the aftertreatment system based on power demand of the first component and a configurable emissivity value of the exhaust gas is determined, and the temperature of the first component based on the calculated heat transfer is calculated.

Abstract: The present disclosure relates to improved systems and methods for use in connection with maintaining the coolant system of a vehicle. Specifically, the present disclosure relates to improved systems and methods for monitoring the integrity of the coolant system in an engine, including capabilities for diagnosing leaks, degradation of coolant, open and/or loose radiator caps, and other sources of potential malfunctions. Early diagnosis and continuous monitoring of an engine coolant system results in earlier repairs and less vehicle downtime.

Abstract: A load adaptive linear electrical generator system is provided for generating DC electrical power. The electrical generation system includes one or more power generation modules which will be selectively turned on or off and additively contribute power depending on the DC power demand. Each power generating module includes a pair of linear electrical generators connected to respective ones of a pair of internal combustion piston based power assemblies. The piston in the internal combustion assembly is connected to a magnet in the linear electrical generator. The piston/magnet assembly oscillates in a simple harmonic motion at a frequency dependent on a power load of the electrical generator. A stroke limiter constrains the piston/magnet assembly motion to preset limits.

Abstract: A passive prechamber spark plug for use in a combustion chamber of a vehicle engine includes an upper prechamber having an upper opening where the upper prechamber is connectable to the combustion chamber via the upper opening. An air ignition spark is formable via an upper air spark gap. A central electrode is disposed in an upper region of the upper prechamber where a base of the upper prechamber opposite the upper region is an insulator. An electrically conductive element or a slot is guided by the insulator continuously from the upper prechamber into a lower region under the base and the lower region is either a lower prechamber or is arrangeable directly in the combustion chamber. An earth electrode is disposed in the lower region such that a lower air-surface gap spark gap is formed between the earth electrode and the electrically conductive element or the slot.

Abstract: A pre-chamber spark plug has a pre-chamber which has openings, where, with respect to a first plane running in the longitudinal direction of the pre-chamber and dividing the pre-chamber into two halves of equal size, first openings are disposed in a first of the halves and second openings are disposed in a second of the halves. The first openings are spaced apart from a second plane running in the longitudinal direction of the pre-chamber and extending perpendicular to the first plane by a first angle in the circumferential direction of the pre-chamber. The second openings are spaced apart from the second plane by a second angle in the circumferential direction of the pre-chamber. The mean value of the first angles is smaller than the mean value of the second angles.

Abstract: A pre-chamber spark plug for a combustion chamber of an internal combustion engine includes a pre-chamber which has a plurality of openings and which is fluidically connectable to the combustion chamber via the plurality of openings. A fuel/air mixture is introducible from the combustion chamber into the pre-chamber via the plurality of openings. Each of the plurality of openings has a respective flow cross section through which the fuel/air mixture is flowable. With respect to an imaginary plane running along an imaginary axis of the pre-chamber and dividing the pre-chamber into a first half and a second half of equal size, a sum of the flow cross sections of first openings disposed in the first half is greater than a sum of the flow cross-sections of second openings disposed in the second half.

Abstract: An ignition system for an internal combustion engine includes a spark plug including a prechamber in which a spark gap is located. A plug cover covers the prechamber and includes an ejection hole, which connects the prechamber to a main combustion chamber of the internal combustion engine. The ignition system for the internal combustion engine is configured to apply a pre-discharge voltage that causes a pre-discharge across the spark gap during an intake stroke of the internal combustion engine.

Abstract: A forced-induction device includes a turbine wheel, a turbine housing, and a connection pipe. The connection pipe includes a partition wall that partitions the inside of the connection pipe into a first passage and a second passage. When a cross section orthogonal to a rotation axis of the turbine wheel is viewed, a line segment extending from the distal end of the partition wall toward the upstream side in the flow direction of exhaust gas and defining a boundary between the first passage and the partition wall is a first downstream line segment. A line segment extending from the distal end of the partition wall toward the upstream side in the flow direction of exhaust gas and defining a boundary between the second passage and the partition wall is a second downstream line segment. The first downstream line segment and the second downstream line segment are parallel to each other.