阅读说明：本技术 集成气缸盖流体喷射设备 (Integrated cylinder head fluid injection apparatus ) 是由 克里斯多夫·唐纳德·威克斯 于 2019-07-09 设计创作，主要内容包括：本公开提供了“集成气缸盖流体喷射设备”。提供了用于一体地形成在气缸盖中的流体喷射布置的方法和系统。在一个实例中,一种方法可包括将聚合物复合结构作为单部件模制,流体喷射布置一体地布置在其中。(The present disclosure provides an "integrated cylinder head fluid injection apparatus". Methods and systems are provided for a fluid injection arrangement integrally formed in a cylinder head. In one example, a method may include molding a polymer composite structure as a single part with a fluid ejection arrangement integrally disposed therein.)

1. A system, comprising:

an engine comprising an inner metal structure disposed on a combustion chamber side of an outer polymer composite structure, wherein the outer polymer composite structure is molded as a single part over and at least partially surrounds the inner metal structure, and wherein the inner metal structure comprises a fluid injection arrangement integrally formed therein.

2. The system of claim 1, wherein the fluid ejection arrangement comprises a main fluid channel and a plurality of valves disposed outside the inner metallic structure.

3. The system of claim 2, wherein a plurality of secondary fluid channels extend from the primary fluid channel and are fluidly coupled to a plurality of internal fluid channels integrally formed in the internal metallic structure.

4. The system of claim 3, wherein a number of the plurality of secondary fluid passages is equal to a number of the plurality of valves.

5. The system of claim 3, wherein the plurality of internal fluid passages are divided within the internal metallic structure to flow fluid to a plurality of injection ports.

6. The system of claim 1, wherein the fluid ejection arrangement is disposed on an exhaust side of the inner metal structure.

7. The system of claim 1, wherein the fluid injection arrangement is shaped to inject fluid near an exhaust port of the combustion chamber.

8. An engine cylinder head, comprising:

a lower portion comprising an inner metal structure; and

an upper portion comprising an outer polymer composite structure at least partially surrounding the inner metal structure,

wherein the inner metallic structure is integrally formed with a fluid injection arrangement comprising a plurality of inner fluid channels fluidly coupled to a plurality of injection ports arranged adjacent to an exhaust port of a combustion chamber.

9. The engine cylinder head of claim 8, wherein the outer polymer composite structure is in coplanar contact with the inner metal structure.

10. The engine cylinder head of claim 8, wherein the internal fluid passage is fluidly coupled to a fluid passage of a portion of the fluid injection arrangement disposed outside of the inner metallic structure.

11. The engine cylinder head of claim 10, wherein said main fluid passage is disposed adjacent and external to an exhaust side of said inner metallic structure.

12. The engine cylinder head of claim 8, wherein the plurality of injection ports are positioned to inject toward one or more of an exhaust port and a center spark plug and a fuel injection zone.

13. The engine cylinder head of claim 8, wherein the fluid injection arrangement does not extend into or contact the outer polymer composite structure.

14. The engine cylinder head of claim 8, wherein the fluid injection arrangement comprises a main fluid passage and a plurality of auxiliary fluid passages disposed outside the inner metallic structure, wherein the main fluid passage and the plurality of auxiliary fluid passages comprise tubes for guiding fluid, and wherein an inner surface of the inner metallic structure is shaped to guide fluid in the plurality of inner fluid passages.

15. The engine cylinder head of claim 14, wherein the fluid injection arrangement further comprises a plurality of valves shaped to regulate the flow of fluid through each of the secondary fluid passages.

Technical Field

The present description generally relates to a fluid injection arrangement integrally formed within a cylinder head.

Background

The cylinder head may comprise a material such as cast iron and/or aluminum. Metal cylinder heads, such as those made of cast iron, can be heavy and exhibit low thermal conductivity. While aluminum cylinder heads may be lighter, they are more expensive to manufacture than cast iron cylinder heads. In addition, aluminum cylinder heads may exhibit insufficient corrosion resistance and undesirable thermal expansion in some instances. Other types of cylinder heads may include stainless steel, ceramic composites, magnesium, and the like. However, these cylinder heads may also have similar drawbacks.

However, the present inventors have recognized more potential problems with such systems. As one example, arranging auxiliary components (such as a fluid injection arrangement) into an already formed cylinder head can be cumbersome and expensive. In addition, packaging limitations may exist with the assembly of the secondary components, thereby limiting the size and/or shape of the secondary components.

Disclosure of Invention

In one example, the above-described problems may be solved by a method of molding an outer polymer composite structure to at least partially surround an inner metal structure including a fluid ejection device integrally formed therein. In this way, the complexity and manufacturing cost of the cylinder head may be reduced relative to the previous examples.

As one example, 3D printing cylinder heads and fluid ejection arrangements may allow for integration of more complex features that were difficult to achieve using previous manufacturing methods. These features may include molding at least a portion of the cylinder head with the cylinder head having a fluid passage shaped to flow fluid from a fluid injection arrangement to one or more injection nozzles disposed adjacent to one or more cylinders. Since the cylinder head and fluid ejection arrangement are 3D printed as a single component, the ejection nozzles may be smaller than the nozzles used in the previous examples. Smaller injection nozzles may allow for the introduction of a greater number of injection nozzles, thereby providing greater injection control, without affecting combustion conditions due to injection nozzle size and/or location.

It should be appreciated that the summary above is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.

Drawings

Fig. 1 shows a schematic view of an engine included in a hybrid vehicle.

FIG. 2 shows a view of the cylinder head without the valve cover, exposing the intake and exhaust ports and the fluid injection arrangement.

Fig. 3 illustrates a view of one or more fluid ejection nozzles adjacent to one or more exhaust ports.

FIG. 4 shows a cross-sectional view of a cylinder head exposing fluid passages extending from a fluid manifold toward exhaust ports.

Fig. 5 shows a perspective view of the fluid channel.

Fig. 6 shows a three-dimensional view of a single fluid ejection nozzle.

FIG. 7 illustrates a method for forming a cylinder head with a fluid injection arrangement.

Fig. 2 to 6 are shown substantially to scale.

Detailed Description

The following description relates to systems and methods for integrally forming a cylinder head and a fluid injection arrangement as a single component. Forming the cylinder head may also include forming one or more conduits within the cylinder head to flow fluid from the fluid injection manifold to the one or more fluid injection nozzles. The cylinder head may be further shaped to house one or more valves, one or more fuel injectors, spark plugs, etc., as shown in fig. 1.

In fig. 2, intake ports and exhaust ports of a plurality of cylinders are exposed. The fluid injection arrangement may be integrally formed with the cylinder head such that the fluid injection nozzle and the fluid passages leading from the fluid injection manifold to the nozzle may be formed as a single component with at least a portion of the cylinder head. The fluid ejection nozzle is further illustrated in fig. 3. The fluid channels may be formed during printing of the cylinder head, as shown in fig. 4. Where the channels are shown diverging towards the location of the fluid ejection orifices. A perspective view of the fluid ejection orifices and fluid ejection channels leading thereto is shown in fig. 5. A close-up view of a fluid ejection nozzle of the plurality of fluid ejection nozzles is shown in fig. 6. A method for manufacturing a cylinder head and fluid injection arrangement is shown in fig. 7.

Fig. 1 to 6 show exemplary configurations in the case of relative positioning of various components. Such elements, at least in one instance, may be referred to as being in direct contact or directly coupled, respectively, if shown as being in direct contact or directly coupled to one another. Similarly, elements shown as abutting or adjacent to each other may be abutting or adjacent to each other, respectively, at least in one example. As one example, components placed in coplanar contact with each other may be referred to as coplanar contacts. As another example, in at least one instance, elements that are positioned apart from one another such that there is only a space between them without other components may be so called. As yet another example, elements shown above/below each other, on opposite sides of each other, or on left/right sides of each other may be so-called with respect to each other. Further, as shown, in at least one example, the topmost element or the topmost point of an element may be referred to as the "top" of the component, and the bottommost element or the bottommost point of an element may be referred to as the "bottom" of the component. As used herein, top/bottom, upper/lower, above/below may be with respect to the vertical axis of the drawings and are used to describe the positioning of elements in the drawings with respect to each other. Thus, in one example, an element shown as being above other elements is positioned vertically above the other elements. As yet another example, the shapes of the elements shown in the figures may be referred to as having those shapes (e.g., such as rounded, rectilinear, planar, curved, rounded, chamfered, angled, etc.). Further, in at least one example, elements shown as intersecting one another may be referred to as intersecting elements or as intersecting one another. Also, in one example, an element shown in another element or shown in another element may be referred to as such. It should be appreciated that one or more components referred to as "substantially similar and/or identical" may differ from one another (e.g., within a 1% to 5% deviation) depending on manufacturing tolerances.

FIG. 1 depicts an engine system 100 for a vehicle. The vehicle may be a road vehicle having a drive wheel in contact with a road surface. The engine system 100 includes an engine 10, the engine 10 including a plurality of cylinders. One such cylinder or combustion chamber is depicted in detail in fig. 1. Various components of engine 10 may be controlled by an electronic engine controller 12.

The engine 10 includes a cylinder block 14 and a cylinder head 16, the cylinder block 14 including at least one cylinder bore 20, the cylinder head 16 including an intake valve 152 and an exhaust valve 154. In other examples, cylinder head 16 may include one or more intake ports and/or exhaust ports in examples where engine 10 is configured as a two-stroke engine. Cylinder block 14 includes a cylinder wall 32 with a piston 36 located in cylinder wall 32 and connected to a crankshaft 40. Thus, when coupled together, the cylinder head 16 and the cylinder block 14 may form one or more combustion chambers. Accordingly, the volume of combustion chamber 30 is adjusted based on the oscillation of piston 36. Combustion chamber 30 may also be referred to herein as a cylinder 30. Combustion chamber 30 is shown communicating with intake manifold 144 and exhaust manifold 148 via respective intake valve 152 and exhaust valve 154. Each intake and exhaust valve may be operated by an intake cam 51 and an exhaust cam 53. Alternatively, one or more of the intake and exhaust valves may be operated by an electromechanically controlled valve coil and armature assembly. The position of the intake cam 51 may be determined by an intake cam sensor 55. The position of the exhaust cam 53 may be determined by an exhaust cam sensor 57. Thus, when valves 152 and 154 are closed, combustion chamber 30 and the cylinder bore may be fluidly sealed such that gases do not enter or exit combustion chamber 30.

Combustion chamber 30 may be formed by cylinder wall 32 of cylinder block 14, piston 36, and cylinder head 16. Cylinder block 14 may include cylinder walls 32, pistons 36, a crankshaft 40, and the like. Cylinder head 16 may include one or more fuel injectors (such as fuel injector 66), one or more intake valves 152, and one or more exhaust valves (such as exhaust valve 154). Cylinder head 16 may be coupled to cylinder block 14 via fasteners, such as bolts and/or screws. In particular, when coupled, the cylinder block 14 and the cylinder head 16 may be in sealing contact with each other via a gasket, and thus the cylinder block 14 and the cylinder head 16 may seal the combustion chamber 30 such that gas may flow into and/or out of the combustion chamber 30 via only the intake manifold 144 when the intake valve 152 is open, and/or flow into and/or out of the combustion chamber via only the exhaust manifold 148 when the exhaust valve 154 is open. In some examples, each combustion chamber 30 may include only one intake valve and one exhaust valve. However, in other examples, more than one intake valve and/or more than one exhaust valve may be included in each combustion chamber 30 of engine 10.

In some examples, each cylinder of engine 10 may include a spark plug 192 for initiating combustion. Ignition system 190 can provide an ignition spark to cylinder 14 via spark plug 192 in response to spark advance signal SA from controller 12, under select operating modes. However, in some embodiments, spark plug 192 may be omitted, such as where engine 10 may initiate combustion by auto-ignition or by injection of fuel, as may be the case with some diesel engines.

Fuel injector 66 may be positioned to inject fuel directly into combustion chamber 30, as is known to those skilled in the art of direct injection. Fuel injector 66 delivers liquid fuel in proportion to the pulse width of the Fuel Pulse Width (FPW) signal from controller 12. Fuel is delivered to fuel injector 66 by a fuel system (not shown) including a fuel tank, fuel pump, and fuel rail. Fuel injector 66 is supplied operating current from driver 68, which is responsive to controller 12. In some examples, engine 10 may be a gasoline engine and the fuel tank may include gasoline, which may be injected by injector 66 into combustion chamber 30. However, in other examples, engine 10 may be a diesel engine and the fuel tank may include diesel fuel, which may be injected into the combustion chamber by injector 66. Further, in such examples where engine 10 is configured as a diesel engine, engine 10 may include glow plugs to initiate combustion in combustion chambers 30.

Intake manifold 144 is shown communicating with throttle 62, which adjusts the position of throttle plate 64 to control airflow to engine cylinders 30. This may include controlling the flow of charge air from intake plenum 146. In some embodiments, throttle 62 may be omitted and airflow to the engine may be controlled via a single intake system throttle (AIS throttle) 82 coupled to intake passage 42 and located upstream of intake plenum 146. In another example, AIS throttle 82 may be omitted, and air flow to the engine may be controlled using throttle 62.

In some embodiments, engine 10 is configured to provide exhaust gas recirculation or EGR. When EGR is included, EGR may be provided as high pressure EGR and/or low pressure EGR. In the example where engine 10 includes low pressure EGR, low pressure EGR may be provided from a location in the exhaust system downstream of turbine 164 via EGR passage 135 and EGR valve 138 to the engine intake system at a location downstream of intake system (AIS) throttle 82 and upstream of compressor 162. EGR may be drawn from the exhaust system to the intake system when a differential pressure exists that drives flow. A pressure differential may be created by partially closing AIS throttle 82. Throttle plate 84 controls the pressure at the inlet of compressor 162. The AIS may be electronically controlled and its position may be adjusted based on an optional position sensor 88.

Ambient air is drawn into combustion chamber 30 via intake passage 42, which intake passage 42 includes an air cleaner 156. Therefore, air first enters the intake passage 42 through the air cleaner 156. Compressor 162 then draws air from intake passage 42 to supply compressed air to plenum 146 via a compressor outlet duct (not shown in fig. 1). In some examples, intake passage 42 may include an air box (not shown) having a filter. In one example, compressor 162 may be a turbocharger, wherein power of compressor 162 is drawn from the exhaust flow through turbine 164. Specifically, the exhaust gas may rotate a turbine 164, which is coupled to a compressor 162 via a shaft 161. Wastegate 72 allows exhaust gas to bypass turbine 164 so that boost pressure may be controlled under varying conditions. The wastegate 72 may be closed (or the wastegate opening may be decreased) in response to an increased boost demand, such as during a driver tip-in. By closing the wastegate, exhaust pressure upstream of the turbine may be increased, thereby increasing turbine speed and peak power output. This allows the boost pressure to be raised. Additionally, when the compressor recirculation valve is partially open, the wastegate may move toward a closed position to maintain a desired boost pressure. In another example, the wastegate 72 may be opened (or the opening of the wastegate may be increased) in response to a decreased boost demand, such as during driver tip-out. By opening the wastegate, the exhaust pressure may be reduced, thereby reducing turbine speed and turbine power. This allows the boost pressure to be reduced.

However, in an alternative embodiment, compressor 162 may be a supercharger, wherein power to compressor 162 is drawn from crankshaft 40. Thus, compressor 162 may be coupled to crankshaft 40 via a mechanical linkage, such as a belt. Accordingly, a portion of the rotational energy output by crankshaft 40 may be transferred to compressor 162 to power compressor 162.

A compressor recirculation valve 158(CRV) may be disposed in a compressor recirculation path 159 around the compressor 162 such that air may be moved from the compressor outlet to the compressor inlet in order to reduce the pressure that may be generated on the compressor 162. Charge air cooler 157 may be positioned in plenum 146 downstream of compressor 162 for cooling the charge air delivered to the engine intake. However, in other examples as shown in FIG. 1, charge air cooler 157 may be positioned downstream of electronic throttle 62 in intake manifold 144. In some examples, charge air cooler 157 may be an air-to-air charge air cooler. However, in other examples, charge air cooler 157 may be a liquid-to-air cooler.

In the depicted example, the compressor recirculation path 159 is configured to recirculate cooled compressed air from upstream of the charge air cooler 157 to the compressor inlet. In an alternative example, the compressor recirculation path 159 may be configured to recirculate compressed air from downstream of the compressor and downstream of the charge air cooler 157 to the compressor inlet. CRV158 may be opened and closed via electrical signals from controller 12. CRV158 may be configured as a three-state valve having a default half-open position that may be moved from the default half-open position to a fully open position or a fully closed position.

Universal Exhaust Gas Oxygen (UEGO) sensor 126 is shown coupled to exhaust manifold 148 upstream of emission control device 70. Alternatively, the two-state exhaust gas oxygen sensor may be replaced with UEGO sensor 126. In one example, emission control device 70 may include a plurality of bricks. In another example, multiple emission control devices may be used, each having multiple bricks. While the depicted example shows UEGO sensor 126 upstream of turbine 164, it should be appreciated that in an alternative embodimentThe UEGO sensor may be positioned in the exhaust manifold downstream of turbine 164 and upstream of emission control device 70. Additionally or alternatively, emission control device 70 may include a Diesel Oxidation Catalyst (DOC) and/or a diesel cold start catalyst, a particulate filter, a three-way catalyst, NO_xTraps, selective catalytic reduction devices, and combinations thereof. In some examples, a sensor may be disposed upstream or downstream of emission control device 70, wherein the sensor may be configured to diagnose a condition of emission control device 70.

The controller 12 is shown in fig. 1 as a microcomputer including: microprocessor unit 102, input/output ports 104, read only memory 106, random access memory 108, keep alive memory 110 and a conventional data bus. Controller 12 is shown receiving various signals from sensors coupled to engine 10, in addition to those signals previously discussed, including: engine Coolant Temperature (ECT) from temperature sensor 112 coupled to cooling sleeve 114; a position sensor 134 coupled to the input device 130 for sensing an input device Pedal Position (PP) adjusted by the vehicle operator 132; a knock sensor (not shown) for determining end gas ignition; a measurement of engine manifold pressure (MAP) from pressure sensor 121 coupled to intake manifold 144; a measurement of boost pressure from pressure sensor 122 coupled to boost chamber 146; an engine position sensor from a Hall effect sensor 118 sensing a position of crankshaft 40; a measurement of air mass entering the engine from a sensor 120 (e.g., a hot wire air flow meter); and a measurement of throttle position from sensor 58. Atmospheric pressure may also be sensed (sensor not shown) for processing by controller 12. In a preferred aspect of the present description, the Hall effect sensor 118 produces a predetermined number of equally spaced pulses per revolution of the crankshaft from which engine speed (RPM) can be determined. Input device 130 may include an accelerator pedal and/or a brake pedal. Accordingly, the output from position sensor 134 may be used to determine the position of the accelerator pedal and/or brake pedal of input device 130, and thus the desired engine torque. Thus, the desired engine torque requested by the vehicle operator 132 may be estimated based on the pedal position of the input device 130.

In some examples, the vehicle 5 may be a hybrid vehicle having multiple torque sources available for one or more wheels 59. In other examples, the vehicle 5 is a conventional vehicle having only an engine, or an electric vehicle having only one or more electric machines. In the illustrated example, the vehicle 5 includes an engine 10 and a motor 52. The electric machine 52 may be a motor or a motor/generator. When the one or more clutches 56 are engaged, the crankshaft 40 of the engine 10 and the electric machine 52 are connected to wheels 59 via the transmission 54. In the depicted example, the first clutch 56 is disposed between the crankshaft 40 and the electric machine 52, while the second clutch 56 is disposed between the electric machine 52 and the transmission 54. Controller 12 may send signals to the actuator of each clutch 56 to engage or disengage the clutch to connect or disconnect crankshaft 40 from motor 52 and components connected thereto, and/or to connect or disconnect motor 52 from transmission 54 and components connected thereto. The transmission 54 may be a gearbox, a planetary gear system, or another type of transmission. The powertrain may be configured in various ways, including a parallel, series, or series-parallel hybrid vehicle.

The electric machine 52 receives power from the traction battery 58 to provide torque to the wheels 59. The electric machine 52 may also operate as a generator to provide electrical power to charge the battery 58, for example, during braking operations.

The controller 12 receives signals from the various sensors of FIG. 1 and employs the various actuators of FIG. 1 to adjust engine operation based on the received signals and instructions stored on a memory of the controller. For example, the operation of the motor 52 may be adjusted based on feedback from the ECT sensor 112. As another example, the controller may receive feedback regarding one or more combustion conditions and actuate one or more valves of the fluid injection arrangement in response to the one or more conditions. Valves and fluid ejection arrangements are described in more detail herein.

Turning now to FIG. 2, an embodiment 200 of the cylinder head 16 of the engine 10 is shown. Accordingly, previously described components may be similarly numbered in subsequent figures. The cylinder head 16 may be fabricated via, at least in part, 3-D printing of various materials based on one or more desired characteristics, such as durability, heat transfer, and packaging constraints. In some examples, the cylinder head 16 may include one or more materials, including metals, carbon fibers, magnesium, titanium, aluminum, cast iron, and ceramic compositions, wherein these materials may be coated with a thermal coating, such as a ceramic coating, molybdenum coating, or other similar coating.

More specifically, the cylinder head 16 may include a first portion 214 and a second portion 216. The first portion 214 may be referred to herein as an inner metal structure 214. The inner metal structure 214 may be a portion that forms an upper portion of the combustion chamber and/or cylinder head. In some embodiments, the inner metal structure may additionally or alternatively include one or more valve stem guides, an exhaust face, one or more intake valve spring seats, one or more exhaust valve spring seats, a flame shield, one or more domes of one or more combustion chambers, and one or more bolt posts. The inner metallic structure 214 may be made of aluminum, textured aluminum, cast iron, CGI iron, steel, or another metal. The inner metallic structure 214 may comprise one or more alloys. For example, the inner metallic structure 214 may include an aluminum alloy including copper, silicon, manganese, magnesium, or the like, or combinations thereof, which may be used as a thermal coating. More specifically, the addition of a thermal coating can reduce thermal expansion and contraction, improve durability, and increase castability of the internal metal structure. The inner metallic structure 214 may be fabricated as a single part via casting, single crystal casting (monocasting), molding, welding, or by other similar methods.

The second portion 216 may be referred to herein as an outer polymer composite structure 216. In some examples, the outer polymer composite structure 216 may include one or more of a reinforced polymer material, a thermoplastic material, and a thermoset resin. The thermosetting resin may include polyester resins, epoxy resins, phenolic resins, polyurethanes, polyimides, silicones, or other types of resins, and combinations thereof. The outer polymer composite structure 216 may be reinforced with a fibrous material, such as a fiber reinforced polymer including one or more of carbon fibers, aramid fibers, glass, basalt, and the like. The outer polymer composite structure 216 may be formed by disposing the inner metallic structure 214 in a mold, wherein the inner metallic structure 214 is tempered and the mold is closed. The composite material is supplied to a mold, wherein the outer polymer composite structure is shaped by molding, during which the composite material is cured. The outer polymer composite structure 216 may include one or more of a coolant jacket, a valve spring pocket, a spark plug and direct injection pocket, a fuel pump pocket, one or more oil feeds to a cam, an intake mounting port, and the like.

In this manner, the embodiment 200 may be illustrated from a cylinder block side view. Accordingly, the inner metallic structure 214 may be closer to one or more of the cylinder block, the piston, the ground on which the vehicle is disposed, etc., than the outer polymeric composite structure.

A plurality of aperture supports 218 may be disposed adjacent to the flame retardant panel 219 of the inner metal structure 214. The plurality of hole supports 218 may be shaped to facilitate alignment of one or more of the combustion chamber, the outer polymer composite structure 216, and the inner metallic structure 214. The plurality of hole supports 218 may be further configured to act as a cooling bridge backing feature.

The illustrated shafting 290 includes three axes, namely an x-axis parallel to the horizontal direction, a y-axis parallel to the vertical direction, and a z-axis perpendicular to each of the x-axis and the y-axis. An intake side 211 and an exhaust side 212 of the cylinder head 16 are shown.

Cylinder bank 202 is shown to include a plurality of cylinders 203. In one example, cylinders of the plurality of cylinders 203 may be used substantially similar to cylinder 30 of fig. 1. In some examples, cylinder group 202 and plurality of cylinders 203 are a first cylinder group and a first plurality of cylinders, wherein the second cylinder group includes a second plurality of cylinders, wherein the first plurality of cylinders and the second plurality of cylinders include an equal number of cylinders. In some embodiments, the first and second pluralities of cylinders may each include four cylinders and may be arranged in a V-shaped configuration such that engine 10 of fig. 1 is a V8 engine. However, it should be understood that the cylinder banks may be arranged directly opposite each other in a box-like configuration. Additionally or alternatively, each cylinder group may include a plurality of cylinders less than or greater than four.

Each cylinder of the cylinder bank 202 may include a plurality of intake ports 204 and a plurality of exhaust ports 206. The plurality of intake ports 204 may fluidly couple the combustion chambers to the intake passages. The plurality of exhaust ports 206 may fluidly couple the combustion chamber to an exhaust passage (e.g., exhaust passage 148 of fig. 1). Intake air flow into the combustion chamber may be metered via one or more of a throttle and an intake valve, and exhaust gas flow out of the combustion chamber may be metered via an exhaust valve. The spark plug and direct injection region 292 may be disposed along a vertical axis between the intake port 204 and the exhaust port 206, directly below the spark plug and fuel injection nest of the outer polymer composite structure 216. In some examples, spark plug 192 of fig. 1 may be vertically aligned with spark plug and direct injection zone 292. Port fuel injection region 294 may correspond to a location of at least one port fuel injector, such as fuel injector 66 of fig. 1. Additionally or alternatively, a center fuel injector may be disposed adjacent to spark plug region 292.

As shown, the intake port 204 and the exhaust port 206 are integrally formed with the inner metallic structure 214. To reduce manufacturing costs, only the exhaust port 206 may include the thermal coating described above. Due to the lower temperature relative to the exhaust port 206, the intake port 204 may not be exposed to the same thermal stresses present in the exhaust port 206 and may not have a thermal coating.

A fluid injection arrangement 220 may be disposed along the exhaust side 212, including a primary fluid passage 222 that may be fluidly coupled to a plurality of secondary fluid passages 224. As shown, the primary fluid channels 222 may be disposed outside each of the inner metallic structure 214 and the polymer composite structure 216. In some examples, additionally or alternatively, the primary fluid channel 222 may be integrally formed in at least the inner metal structure 214 without departing from the scope of the present disclosure. In one example, at least a portion of the primary fluid channels 222 are disposed within the inner metallic structure 214 and the remaining portion is disposed outside of the inner metallic structure 214. During molding of the outer polymer composite structure 216, the outer polymer composite structure 216 may optionally be molded around at least a portion of the remainder of the main fluid channel 222. In one example, the primary fluid channels 222 are disposed entirely outside each of the inner metallic structure 214 and the outer polymeric composite structure 216.

The secondary fluid passage 224 may extend from the primary fluid passage 222, through the inner metallic structure 214 and its thermal coating, to a location adjacent the exhaust port 206. Additionally or alternatively, the inner metallic structure 214 may include a plurality of inner fluid channels that fluidly couple the auxiliary fluid channels, as will be described in more detail with reference to fig. 4.

In some examples, such as the example shown in fig. 2, fluid flow from the primary fluid passage 222 through each of the secondary fluid passages 224 may be metered and/or regulated via one or more valves 226. More specifically, fluid flow from the main fluid passage 222 to the first auxiliary fluid passage 224A may be regulated via the first valve 226A. Fluid flow from the primary fluid passage 222 to the second secondary fluid passage 224B may be regulated via the second valve 226B. Fluid flow from the primary fluid passage 222 to the third auxiliary fluid passage 224C may be regulated via a third valve 226C. Fluid flow from the main fluid passage 222 to the fourth auxiliary fluid passage 224D may be regulated via a fourth valve 226D. Valve 226 may be disposed on a portion of auxiliary fluid channel 224 that is external to inner metallic structure 214. As shown, each of the primary fluid passage 222 and the secondary fluid passage 224 is formed via a tube.

The first auxiliary fluid passage 224A may correspond to the first cylinder 202A of the cylinder bank 202 such that the first valve 226A regulates fluid flow to only the first cylinder 202A. The second auxiliary fluid passage 224B may correspond to the second cylinder 202B such that the second valve 226B regulates fluid flow to only the second cylinder 202B. The third auxiliary fluid passage 224C may correspond to the third cylinder 202C such that the third valve 226C regulates fluid flow to only the third cylinder 202C. The fourth auxiliary fluid passage 224D may correspond to the fourth cylinder 202D such that the fourth valve 226D regulates fluid flow to only the fourth cylinder 202D. The fluid flow in one of the secondary fluid passages 224 may not mix with the fluid flow in a different secondary fluid passage 224. For example, fluid in first auxiliary fluid channel 224A may not mix with fluid in second auxiliary fluid channel 224B, third auxiliary fluid channel 224C, or fourth auxiliary fluid channel 224D.

Each of the plurality of cylinders 203 includes an injection port 228, the injection port 228 being shaped to inject fluid from the secondary fluid passage 224 toward the exhaust port 206. In this manner, exhaust gas may mix with the fluid as it flows from any of the plurality of cylinders 203 through the exhaust port 206 toward the exhaust passage (e.g., exhaust passage 148 of fig. 1). Additionally or alternatively, none or some of the cylinders of cylinder group 202 may flow exhaust mixed with fluid, while all or other cylinders may only flow exhaust free of fluid based on the position of one or more valves 226.

Each of the valves 226 may be adjusted to a fully closed and a fully open position. The fully closed position may prevent fluid flow, and the fully open position may allow maximum fluid flow. As one example, if the first valve 226A is in a fully closed position (e.g., 0% open), fluid from the main fluid passage 222 may not flow into the first auxiliary fluid passage 224A. As another example, if the third valve 226C is in a fully open position (e.g., 100% open), fluid from the primary fluid passage 222 may flow into the third auxiliary fluid passage 224A at a highest rate (e.g., 100% flow). Additionally or alternatively, the valve 226 may include additional controls to actuate between a fully closed position and a fully open position such that fluid flow may be regulated to a greater extent. For example, the valve 226 may be adjusted to a more open position or a more closed position, wherein the more open position may allow a greater amount of fluid flow than the more closed position. In one example, the valve 226 may be actuated to a position of 0%, 100%, or in between.

The fluid injection arrangement 220 may be shaped to inject one or more fluids including water, ethanol, gasoline, reductants, catalytic solutions, combustion stabilizers, combinations thereof, and the like. In one example, the fluid injection arrangement 220 injects ethanol. Additionally or alternatively, the fluid injection arrangement 220 injects water. The fluid of the fluid injection arrangement 220 may not be mixed with other fluids of the engine and/or vehicle. In one example, the fluid of the fluid injection arrangement 220 may not be mixed with the coolant.

Turning now to FIG. 3, a close-up view 300 of a group of jet ports 328 of exhaust port 206 and jet ports 228 is shown. The exhaust port 206 may be coupled to a cylinder of the plurality of cylinders 203 of fig. 2.

The set of injection ports 328 may include at least one injection port. In the example of fig. 3, three ejection ports are shown. However, it should be understood that less than three or more than three ejection ports may be included in the inner metal structure 214 without departing from the scope of the present disclosure. More specifically, the set of injection ports 328 may include a first injection port 328A, a second injection port 328B, and a third injection port 328C. First injection ports 328A, second injection ports 328B, and third injection ports 328C may be substantially the same size and shape. However, the orientation of the jet 328 may be different.

Each injection port of the set of injection ports 328 may be substantially cylindrical. However, it should be understood that the ejection orifice may comprise other shapes such as cubic, pyramidal, or other similar shapes without departing from the scope of the present disclosure. Each of first injection port 328A, second injection port 328B, and third injection port 328C may protrude a distance into the combustion chamber, respectively, as described in more detail with reference to FIG. 6. However, the amount of protrusion (e.g., distance of protrusion) may be less than other fluid ejection arrangements that are not integrally molded and/or 3-D printed with the inner metallic structure 214. Additionally or alternatively, injection ports 328 may be flush with the surface of inner metal structure 214.

More specifically, first injection ports 328A may be directed at a first angle α, and second injection ports 328B may be directed at a second angle β, each of first angle α and second angle β being measured relative to injection axis 390 of third injection ports 328C. The first angle a may be substantially equal to the second angle β. In some examples, the first angle α and the second angle β may be acute angles. Additionally or alternatively, the first angle α and the second angle β may be between 10o and 80 o. Additionally or alternatively, the first angle α and the second angle β may be between 15o and 70 o. Additionally or alternatively, the first angle α and the second angle β may be between 20o and 60 o. Additionally or alternatively, the first angle α and the second angle β may be between 25o and 50 o. Additionally or alternatively, the first angle α and the second angle β may be between 30o and 45 o. In one example, the first angle α and the second angle β are exactly equal to 40 °. Additionally or alternatively, the first angle α and the second angle β may be different from each other.

First injection port 328A may be disposed adjacent to first exhaust port 206A. The first injection ports 328A may be further oriented to inject fluid into the combustion chamber at a region adjacent to the first exhaust port 206A. The second injection ports 328B may be disposed adjacent to the second exhaust ports 206B. The second injection ports 328B may be further oriented to inject fluid into the combustion chamber at a region adjacent to the second exhaust port 206B. By being oriented to eject fluid near one of the exhaust ports 206, exhaust gas flowing through the exhaust port can easily sweep the fluid ejection through the exhaust port, minimizing fluid ejection from penetrating into the cylinder.

Additionally or alternatively, fluid injection timing may be adjusted based on exhaust valve timing to adjust the amount of penetration of the injection. For example, fluid injection timing may be adjusted to be more similar to exhaust valve timing to reduce infiltration into the combustion chamber.

Third injection ports 328C may be disposed between first injection ports 328A and second injection ports 328B. Third injection ports 328C may be further oriented to inject fluid into the combustion chamber at a region adjacent to spark plug region 292. The general injection direction of third injection ports 328C may be along injection axis 390.

In some examples, each of first jet orifice 328A, second jet orifice 328B, and third jet orifice 328C may inject fluid in one or more of a conical, cylindrical, star, or other shape. In some examples, each of first injection orifices 328A, second injection orifices 328B, and third injection orifices 328C may be injected in different shapes. For example, first injection orifices 328A may inject in a cylindrical shape, and third injection orifices 328C may inject in a conical shape.

Turning now to fig. 4, a cross-section 400 of the cylinder head 16 is shown exposing the internal fluid passage 428. More specifically, cross-section 400 shows a first internal fluid passage 428A and a second internal fluid passage 428B. Each internal fluid passage 428 may branch off from the auxiliary fluid passage 224. That is, the auxiliary fluid passage 224 may be fluidly coupled to the inner fluid passage 428. The inner fluid channel 428 may be formed via the inner surface of the inner metallic structure 214 and may be free of tubes forming primary and secondary fluid channels. In some examples, valve 226 may only regulate fluid flow into auxiliary fluid passage 224. In one example, the valve 226 may not regulate fluid flow to each of the internal fluid passages 428. In this manner, fluid in the auxiliary fluid passage 224 may flow to each corresponding internal fluid passage 428 when a corresponding one of the valves 226 is open.

In some embodiments, the number of internal fluid passages 428 branching from the auxiliary fluid passage 224 may equal the number of injection ports positioned to inject into the combustion chamber. In the example of fig. 4, there are three injection ports positioned to inject into the combustion chamber, with the cross-section 400 exposing two of the three internal fluid passages, namely a first internal fluid passage 428A and a second internal fluid passage 428B. In one example, first inner fluid passage 428A may be shaped to flow fluid to first injection port 328A, and second inner fluid passage 428B may be shaped to flow fluid to second injection port 328B of fig. 3. Thus, a third internal fluid passage that may be enclosed in cross-section 400 by a surface of internal metallic structure 214 may be shaped to flow fluid to third jet ports 328C of fig. 3.

The internal fluid passage 428 may be integrally formed as a single piece within the internal metallic structure 214. In one example, the internal fluid channel 428 is not drilled, tapped, or engraved into the internal metallic structure 214. In other words, internal fluid channels 428 may be formed when internal metallic structure 214 is formed.

Turning now to fig. 5, a perspective view 500 of the first and second internal fluid passages 428A, 428B and the set of injection ports 328 is shown. As shown, first internal fluid passage 428A is directly coupled to first injection port 328A, and second internal fluid passage 428B is directly coupled to second injection port 328B. The fluid in the first internal fluid passage 428A may not mix with the fluid in the second internal fluid passage 428B. In one example, the fluid in one of the internal fluid channels does not mix with the fluid in the other internal fluid channel.

The perspective view 500 further illustrates the division of the secondary fluid passage (e.g., secondary fluid passage 224) that creates an inner fluid passage 428 shaped to deliver fluid to the ejection port. In one example, the auxiliary fluid channel may be fluidly coupled to an internal channel of the inner metallic structure 214, wherein the internal channel is trifurcated to flow fluid to each jet port 328.

Turning now to fig. 6, a detailed view 600 of a single injection port 628 of a plurality of injection ports (e.g., injection ports 228 of fig. 2) is shown. The single injection port 628 may be disposed along and extend from an inner metal structure (e.g., inner metal structure 214 of fig. 2) into the combustion chamber. The single injection port 628 may be integrally formed with the inner metal structure. In one example, a single ejection port 628 and other ejection ports (e.g., ejection port 228) are 3-D printed along with the internal metal structure.

The single injection port 628 may protrude into the combustion chamber as described above, wherein the protruding amount may correspond to the length 638 of the single injection port 628. A length 638 of a single jet opening 628 may be substantially equal to the length of other jet openings (e.g., jet openings 228 of fig. 2). The length 638 may be between 0.5mm and 5.0 mm. In some examples, additionally or alternatively, the length 638 may be between 1.0mm and 3.0 mm. In some examples, additionally or alternatively, the length 638 may be between 1.0mm and 2.0 mm. In some examples, additionally or alternatively, the length 638 may be between 1.25mm and 1.75 mm. In one example, the length 638 is equal to 1.6 mm.

In some examples, additionally or alternatively, the single injection port 628 may be flush with a surface of the inner metal structure 214 such that the single injection port 628 does not affect a volume of the combustion chamber. In some examples, additionally or alternatively, the projection of the injection ports may vary such that some injection ports project a distance into the combustion chamber and other injection ports are flush with the surface of the inner metal structure 214.

The single injection port 628 along with other injection ports (such as injection port 228 of fig. 2) may be similarly shaped, where the shape may be cylindrical. The radius 636 of a single injection port 628 may be equal to the radius of the other injection ports (e.g., injection ports 228 of fig. 2). The radius 636 may be between 0.1mm and 5 mm. In some examples, additionally or alternatively, radius 636 may be between 0.5mm and 2 mm. In some examples, additionally or alternatively, radius 636 may be between 0.8mm and 1.5 mm. In one example, radius 636 is equal to 1.0 mm.

In some examples, such as the example of fig. 6, the body of the single injection port 628 may deviate from a cylindrical shape. More specifically, in the example of fig. 6, the body of the single injection port 628 narrows toward one end of the body near one or more injection orifices and/or openings. The narrowed length 639 may be between 0.01mm and 1.0 mm. In some examples, additionally or alternatively, the length 639 may be between 0.1mm and 0.8 mm. In some examples, additionally or alternatively, the length 639 may be between 0.3mm and 0.6 mm. In one example, the length 639 is 0.4 mm.

The single jet opening 628 includes a plurality of openings 630, the plurality of openings 630 including a main opening 632 and a plurality of peripheral openings 634. The main opening 632 may be surrounded by a plurality of peripheral openings 634. The main opening 632 may be similarly shaped as each of the plurality of peripheral openings 634. The shape of the main opening 632 and the plurality of peripheral openings 634 may be triangular, circular, square, rectangular, diamond, trapezoidal, polyhedral, or some other similar shape. Here, the main opening 632 and the plurality of peripheral openings 634 are circular.

The main opening 632 may include a first diameter and each peripheral opening 634 may be the same size and include a second diameter. The first diameter may be larger than the second diameter such that the main opening 632 may eject more fluid than a single one of the peripheral openings 634. However, the total volume of fluid ejected from all peripheral openings 634 may be greater than the volume of fluid ejected from the main opening 632.

The first diameter of the first opening 632 may be between 0.01mm and 1.0 mm. In some examples, additionally or alternatively, the first diameter of the first opening 632 may be between 0.05mm and 0.5 mm. In some examples, additionally or alternatively, the first diameter of the first opening 632 may be between 0.1mm and 0.3 mm. In some examples, additionally or alternatively, the first diameter of the first opening 632 may be between 0.15mm and 0.25 mm. In one example, the first diameter of the first opening 632 is equal to 0.2 mm.

The second diameter of the peripheral opening 634 may be between 0.001mm and 0.5 mm. In some examples, additionally or alternatively, the second diameter of the peripheral opening 634 can be between 0.01mm and 0.25 mm. In some examples, additionally or alternatively, the second diameter of the peripheral opening 634 can be between 0.05mm and 0.1 mm. In some examples, additionally or alternatively, the second diameter of the peripheral opening 634 can be between 0.08mm and 0.1 mm. In one example, the second diameter of the peripheral opening 634 is equal to 0.09 mm.

Turning now to fig. 7, a method 700 for arranging a cylinder head including a fluid injection arrangement as illustrated by fig. 1-6 is illustrated. The method 700 begins at 702, which includes arranging an inner metallic structure having a fluid ejection arrangement at least partially disposed therein. The internal metallic structure may be a portion that forms an upper portion of the combustion chamber. The internal metallic structure may be manufactured as a single part via casting, single crystal casting, molding, welding, 3-D printing, or by other similar methods.

Method 700 may proceed to 704, which may include molding an outer polymer composite structure at least partially surrounding an inner metal structure. The polymer composite structure may be formed by arranging an internal metal structure in a mold, wherein the internal metal structure is tempered and the mold is closed. The composite material is supplied to a mold, wherein the polymer composite structure is shaped by molding, during which the composite material is cured. The molding may also include the outer polymer composite structure not interfering with or covering various portions of the fluid ejection arrangement integrally formed within the inner metal structure such that the auxiliary fluid channel may be fluidly coupled to the inner fluid channel. The polymer composite structure may include one or more of a coolant jacket, a valve spring pocket, a spark plug and direct injection pocket, a fuel pump pocket, one or more oil feeds to a cam, intake mounting ports, fluid injection arrangements, and the like. The coolant jacket may be completely fluidly decoupled from the fluid jet arrangement of the inner metallic structure. In one example, the fluid in the fluid ejection arrangement does not mix with fluid in the coolant jacket or other portions of the coolant system. Thus, the inner metal structure and the outer polymer composite structure may be shaped to accommodate multiple fluid sources and/or channels without allowing mixing therebetween.

In this manner, the cylinder head may be manufactured to reduce manufacturing costs and packaging constraints by at least partially surrounding the inner metal structure with the outer polymer composite structure. Furthermore, the internal metallic structure may be integrally formed with the fluid injection arrangement to further reduce manufacturing costs and packaging constraints while providing a direct injection arrangement in the combustion chamber. The technical effect of integrating the fluid injection arrangement with the internal metal structure is to provide complex features within the combustion chamber while reducing manufacturing time and cost.

An example of a method includes molding an outer polymer composite structure to at least partially surround an inner metal structure including a fluid ejection arrangement integrally formed therein. The first example of the method further includes wherein the inner metal structure further comprises forming one or more inner fluid passages that fluidly couple the main water passage to the plurality of injection ports. A second example of the method (optionally including the first example) further comprises wherein the injection port is disposed adjacent to one or more exhaust ports within the combustion chamber. A third example of the method (optionally including the first and/or second examples) further includes wherein the internal fluid passage is separate from a coolant and oil passage formed in the external polymer composite structure, and wherein fluid in the internal fluid passage is not mixed with fluid from the coolant and oil passage. A fourth example of the method (optionally including one or more of the first through third examples) further includes wherein the inner metallic structure is an upper portion of a combustion chamber, and wherein the inner metallic structure includes a flame retardant panel.

A system comprising an engine comprising an inner metal structure disposed on a combustion chamber side of an outer polymer composite structure, wherein the outer polymer composite structure is molded as a single part over and at least partially surrounds the inner metal structure, and wherein the inner metal structure comprises a fluid injection arrangement integrally formed therein. The first example of the system further includes wherein the fluid ejection arrangement includes a main fluid channel and a plurality of valves disposed outside the inner metallic structure. A second example of the system (optionally including the first example) further includes wherein the plurality of secondary fluid channels extend from the primary fluid channel and are fluidly coupled to a plurality of internal fluid channels integrally formed in the internal metallic structure. A third example of the system (optionally including the first and/or second examples) further includes wherein the number of the plurality of secondary fluid passages is equal to the number of the plurality of valves. A fourth example of the system (optionally including one or more of the first through third examples) further includes wherein the plurality of internal fluid passages are separated within the internal metallic structure to flow fluid to the plurality of injection ports. A fifth embodiment of the system (optionally including one or more of the first through fourth embodiments) further comprises wherein the fluid ejection arrangement is disposed on an exhaust side of the inner metallic structure. A sixth example of the system (optionally including one or more of the first through fifth examples) further includes wherein the fluid injection arrangement is shaped to inject fluid near an exhaust port of the combustion chamber.

An engine cylinder head, comprising: a lower portion comprising an inner metal structure; and an upper portion comprising an outer polymer composite structure at least partially surrounding an inner metal structure, wherein the inner metal structure is integrally formed with a fluid injection arrangement comprising a plurality of inner fluid channels fluidly coupled to a plurality of injection ports arranged adjacent to an exhaust port of a combustion chamber. The first example of an engine cylinder head further includes wherein the outer polymer composite structure is in coplanar contact with the inner metal structure. The second example (optionally including the first example) of the engine cylinder head further includes a fluid passage in which the internal fluid passage is fluidly coupled to a portion of a fluid injection arrangement disposed outside of the internal metallic structure. The third example of an engine cylinder head (optionally including the first and/or second examples) further comprises wherein the primary fluid passage is disposed adjacent and external to the exhaust side of the inner metallic structure. A fourth example of an engine cylinder head (optionally including one or more of the first through third examples) further includes wherein the plurality of injection ports are positioned to inject toward one or more of the exhaust port and the center spark plug and the fuel injection zone. A fifth example of an engine cylinder head (optionally including one or more of the first through fourth examples) further includes wherein the fluid injection arrangement does not extend into or contact the outer polymer composite structure. A sixth example of an engine cylinder head (optionally including one or more of the first through fifth examples) further comprises wherein the fluid injection arrangement comprises a primary fluid passage and a plurality of secondary fluid passages disposed outside the inner metallic structure, wherein the primary fluid passage and the plurality of secondary fluid passages comprise tubes for guiding fluid, and wherein an inner surface of the inner metallic structure is shaped to guide fluid in the plurality of inner fluid passages. The seventh example of the engine cylinder head (optionally including one or more of the first through sixth examples) further comprises wherein the fluid injection arrangement further comprises a plurality of valves shaped to regulate a flow of fluid through each of the secondary fluid passages.

It will be appreciated that the configurations and routines disclosed herein are exemplary in nature, and that these specific embodiments are not to be considered in a limiting sense, because numerous variations are possible. For example, the above techniques may be applied to V-6, I-4, I-6, V-12, opposed 4, and other engine types. The subject matter of the present disclosure includes all novel and non-obvious combinations and subcombinations of the various systems and configurations, and other features, functions, and/or properties disclosed herein.

The following claims particularly point out certain combinations and subcombinations regarded as novel and nonobvious. These claims may refer to "an" element or "a first" element or the equivalent thereof. Such claims should be understood to include incorporation of one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and subcombinations of the disclosed features, functions, elements, and/or properties may be claimed through amendment of the present claims or through presentation of new claims in this or a related application. Such claims, whether broader, narrower, equal, or different in scope to the original claims, also are regarded as included within the subject matter of the present disclosure.

In accordance with the present invention, a method includes molding an outer polymer composite structure to at least partially surround an inner metal structure including a fluid ejection arrangement integrally formed therein.

According to one embodiment, the internal metallic structure further comprises forming one or more internal fluid passages that fluidly couple the main water passage of the engine to the plurality of injection ports of the engine.

According to one embodiment, the injection port is arranged adjacent to one or more exhaust ports within the combustion chamber.

According to one embodiment, the internal fluid channels are separate from the coolant and oil channels formed in the external polymer composite structure, and wherein the fluid in the internal fluid channels is not mixed with fluid from the coolant and oil channels.

According to one embodiment, the internal metal structure is an upper portion of the combustion chamber, and wherein the internal metal structure comprises a fire retardant panel.

According to the present invention, there is provided a system having an engine comprising an inner metal structure disposed on a combustion chamber side of an outer polymer composite structure, wherein the outer polymer composite structure is molded as a single part over and at least partially surrounds the inner metal structure, and wherein the inner metal structure comprises a fluid injection arrangement integrally formed therein.

According to one embodiment, a fluid ejection arrangement includes a main fluid channel and a plurality of valves disposed outside of an inner metal structure.

According to one embodiment, a plurality of secondary fluid channels extend from the primary fluid channel and are fluidly coupled to a plurality of internal fluid channels integrally formed in the internal metallic structure.

According to one embodiment, the number of the plurality of secondary fluid passages is equal to the number of the plurality of valves.

According to one embodiment, the plurality of internal fluid passages are divided within the internal metallic structure to flow fluid to the plurality of injection ports.

According to one embodiment, the fluid ejection arrangement is arranged on an exhaust side of the inner metal structure.

According to one embodiment, the fluid injection arrangement is shaped to inject fluid near an exhaust port of the combustion chamber.

According to the present invention, there is provided an engine cylinder head having: a lower portion comprising an inner metal structure; and an upper portion comprising an outer polymer composite structure at least partially surrounding an inner metal structure, wherein the inner metal structure is integrally formed with a fluid injection arrangement comprising a plurality of inner fluid channels fluidly coupled to a plurality of injection ports arranged adjacent to an exhaust port of a combustion chamber.

According to one embodiment, the outer polymer composite structure is in coplanar contact with the inner metal structure.

According to one embodiment, the internal fluid channel is fluidly coupled to a fluid channel of a portion of a fluid ejection arrangement disposed outside the internal metallic structure.

According to one embodiment, the main fluid channel is arranged near and outside the exhaust side of the inner metal structure.

According to one embodiment, the plurality of injection ports are positioned to inject toward one or more of the exhaust port and the center spark plug and the fuel injection zone.

According to one embodiment, the fluid ejection arrangement does not extend into or contact the outer polymer composite structure.

According to one embodiment, the fluid ejection arrangement comprises a main fluid channel and a plurality of auxiliary fluid channels arranged outside the inner metallic structure, wherein the main fluid channel and the plurality of auxiliary fluid channels comprise tubes for guiding fluid, and wherein an inner surface of the inner metallic structure is shaped to guide fluid in the plurality of inner fluid channels.

According to one embodiment, the fluid ejection arrangement further comprises a plurality of valves shaped to regulate the flow of fluid through each secondary fluid channel.