Arc-shaped inclined cross-cylinder straight air channel cylinder cover and gas engine

Abstract

The invention relates to the technical field of gas engines, and discloses an arc-shaped inclined cross-cylinder straight air duct cylinder cover and a gas engine, the arc-shaped inclined cross-cylinder straight air duct cylinder cover comprises a flat-top cylinder cover, two exhaust ducts, a first air inlet duct and a second air inlet duct, the air inlet ends of the two exhaust ducts are communicated with the cylinder cover, and the two exhaust ducts are arranged on one side of the cylinder cover; the first air inlet channel and the second air inlet channel are tumble air channels, the air outlet ends of the first air inlet channel and the second air inlet channel are communicated with the cylinder cover, a first center face passing through the axis of the cylinder cover is formed among the first air inlet channel, the second air inlet channel and the two exhaust channels, and the included angles between extension lines of projections of the first air inlet channel and the second air inlet channel on the top face of the cylinder cover and the first center face are smaller than 90 degrees. According to the cylinder cover with the arc-shaped inclined cross-cylinder straight air channel, tumble flow and vortex flow can be generated in the cylinder at the same time, turbulent kinetic energy in the cylinder is improved, the flame propagation speed is increased, combustion is accelerated, and therefore the heat efficiency of an engine is improved.

Description

Technical Field

[0001] The invention relates to the technical field of gas engines, and in particular to an arc-shaped inclined cross-cylinder straight airway cylinder head and a gas engine. Background Art

[0002] Heavy-duty gas engines are ignition-type internal combustion engines, similar to gasoline engines. Their combustion form determines the need to organize a certain intensity of tumble flow in the cylinder.

[0003] However, most of the heavy-duty gas engines (including natural gas and hydrogen) at home and abroad in the National VI stage are modified from diesel engines. The intake duct is a vortex air duct. The turbulent kinetic energy in the cylinder is low at the time of ignition. At the same time, large-scale vortexes will increase the tendency of knock, which is not conducive to improving thermal efficiency. In addition, there are also dome tumble air ducts that use gasoline engines to form strong tumble flows in the cylinder, but strong tumble flows may lead to increased cycle variations, affecting the stability and durability of the engine. Summary of the invention

[0004] The purpose of the present invention is to overcome the above technical deficiencies, and to propose an arc-shaped inclined cross-cylinder straight airway cylinder head and a gas engine, so as to solve the technical problem that the use of turbine airways or tumble airways in the prior art affects the performance of the gas engine.

[0005] In order to achieve the above technical objectives, the present invention adopts the following technical solutions: In a first aspect, the present invention provides a cylinder head with an arc-shaped inclined cross-cylinder straight airway, comprising: Flat top cylinder head; Two exhaust passages, the air inlet ends of the two exhaust passages are connected to the cylinder head and are arranged on one side of the cylinder head; The first intake duct and the second intake duct are tumble flow ducts, and the outlet ends are connected to the cylinder head. A first center plane passing through the axis of the cylinder head is formed between the first intake duct, the second intake duct and the two exhaust ducts. The angles between the extended lines of the projections of the first intake duct and the second intake duct on the top surface of the cylinder head and the first center plane are both less than 90°.

[0006] In some embodiments, the first intake duct and the second intake duct both have a first inclined air duct, an arc guide air duct and a second inclined air duct that are sequentially connected along a direction approaching the cylinder head, and the slope of the first inclined air duct is smaller than the slope of the second inclined air duct.

[0007] In some embodiments, a second center plane passing through the axis of the cylinder head is provided between the first air intake passage and the second air intake passage, and in the projection of the first air intake passage and the second air intake passage on the second center plane, the first air intake passage and the second air intake passage have a first straight line segment, a first arc segment and a second straight line segment connected in sequence on one side close to the cylinder head, an angle θ2 between the first straight line segment and the top surface of the cylinder head is in a range of 0° to 15°, an angle R1 of the first arc segment is in a range of 80 mm to 100 mm, and an angle θ1 between the second straight line segment and the top surface of the cylinder head is in a range of 40° to 60°; The first air intake passage and the second air intake passage have a third straight line segment, a second arc segment and a fourth straight line segment connected in sequence on the side away from the cylinder head. The angle θ4 between the third straight line segment and the top surface of the cylinder head is in the range of 20° to 40°, the angle R2 of the second arc segment is in the range of 80 mm to 100 mm, and the angle θ3 between the fourth straight line segment and the top surface of the cylinder head is in the range of 30° to 50°.

[0008] In some embodiments, an angle between an extension line of a projection of the first intake passage and the second intake passage on the top surface of the cylinder head and the first center plane is in a range of 45° to 55°.

[0009] In some embodiments, the two exhaust passages are symmetrically distributed along the second center plane, the spacing between the two exhaust passages gradually decreases in a direction away from the cylinder head, and the outlet ends of the two exhaust passages share an outlet port.

[0010] In some of the embodiments, the side walls of the air outlet ends of the two exhaust passages are provided with a first opening connecting the two exhaust passages.

[0011] In some embodiments, projections of the first air inlet passage and the second air inlet passage on the top surface of the cylinder head are arc-shaped and gradually deviate from the first center plane in a direction away from the cylinder head.

[0012] In a second aspect, the present invention further provides a gas engine, comprising a cylinder head with an arc-shaped inclined cross-cylinder straight air passage as described above.

[0013] In some of the embodiments, the gas engine has a plurality of cylinder heads with arc-shaped inclined cross-cylinder straight air passages, two adjacent second air intake passages in the plurality of cylinder heads with arc-shaped inclined cross-cylinder straight air passages share an air intake port, and the side walls of the air intake ends of the two adjacent second air intake passages are provided with a second opening connecting the two second air intake passages.

[0014] In some of the embodiments, the gas engine further comprises a combustion chamber matched with the cylinder head, wherein the combustion chamber is cylindrical on one side close to the cylinder head, and the inner wall and outer wall of the combustion chamber away from the cylinder head are spherical.

[0015] Compared with the prior art, the arc-shaped inclined cross-cylinder straight-air passage cylinder head and gas engine provided by the present invention, when the mixed gas enters the cylinder, the mixed gas first enters the intake manifold, and then enters the first intake passage and the second intake passage through the intake manifold, and the airflow mainly organizes the flow field in the first intake passage and the second intake passage. Since the first intake passage and the second intake passage adopt tumble flow passages, after the mixed gas enters the cylinder through the first intake passage and the second intake passage, the airflow will form a rotational motion in the vertical direction, that is, tumble flow; since the angle between the extension line of the projection of the first intake passage and the second intake passage on the top surface of the cylinder head and the first center plane is less than 90°, the extension line of the projection of the first intake passage and the second intake passage on the top surface of the cylinder head is inclined to the first center plane, and the mixed gas is arranged based on the inclined After the first intake duct and the second intake duct enter the cylinder, the airflow will form a horizontal rotational motion, namely, a vortex; therefore, after the mixed gas enters the cylinder, it has both tumble and vortex. Through simulation, it is found that, in fact, the airflow of the mixed gas in the cylinder will form a rotational motion inclined in the vertical direction, and the tumble and vortex form a mutually reinforcing effect, which is reflected in the relative increase of the tumble ratio and the swirl ratio; on the other hand, a certain degree of swirl can accelerate combustion in the later stage of combustion, thereby shortening the ignition delay period with tumble, reducing the combustion duration with swirl, comprehensively accelerating the combustion speed, making full use of the compression energy before the top dead center, and effectively improving the thermal efficiency; at the same time, the combination of tumble and turbine can reduce the impact of a single tumble or a turbine that is too large on the performance of the gas engine.

[0016] Moreover, the cylinder head in the present application adopts a flat-top cylinder head. Under the condition of non-dome design, the arc-shaped inclined cross-cylinder straight air duct cylinder head increases the turbulent kinetic energy near the spark plug electrode. After the spark plug is ignited, the fire core diffuses outward at the spark plug electrode position, and the flame can quickly fill the combustion chamber with the tumble and vortex movement, thereby accelerating the combustion speed and improving the thermal efficiency of the whole machine.

[0017] The design of the first intake duct and the second intake duct matching the dual exhaust duct is conducive to smooth airflow organization, increasing the tumble ratio, making full use of turbulent kinetic energy, and accelerating the combustion speed.

[0018] The arc-shaped inclined cross-cylinder straight airway cylinder head of the present invention adopts a flat-top cylinder head, which can be shared with the diesel engine cylinder head production and assembly line, with small initial manufacturing investment, and can make full use of existing resources without large-scale investment. Keeping the boundary conditions of the cylinder head unchanged, by optimizing the structure and layout of the first intake duct and the second intake duct, tumble and vortex can be generated in the cylinder at the same time, thereby increasing the turbulent kinetic energy in the cylinder, accelerating the flame propagation speed, accelerating combustion, and thus improving the thermal efficiency of the engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic structural diagram of a cylinder head with an arc-shaped inclined cross-cylinder straight airway provided by an embodiment of the present invention; Figure 2 It is a structural schematic diagram of a cylinder head with an arc-shaped inclined cross-cylinder straight airway provided by an embodiment of the present invention when it is connected to an adjacent cylinder head with an arc-shaped inclined cross-cylinder straight airway; Figure 3 is a schematic structural diagram of a straight airway cylinder head provided by an embodiment of the present invention; Figure 4 It is a streamline diagram of the airflow in the cylinder head in the prior art; Figure 5 It is a TKE (Turbulence Kinetic Energy) slice diagram of the airflow in the cylinder head of the arc-shaped center-cross-cylinder straight airway provided by an embodiment of the present invention; Figure 6 It is a test diagram of the tumble ratio of the airflow in the cylinder of the cylinder head with an arc-shaped inclined cross-cylinder straight airway in the Y-axis direction provided by an embodiment of the present invention; Figure 7 It is a test diagram of the swirl ratio of the airflow in the cylinder of a cylinder head with an arc-shaped inclined cross-cylinder straight air passage provided by an embodiment of the present invention.

[0020] Description of reference numerals: Cylinder head 1; exhaust passage 2; first intake passage 3; second intake passage 4; first center plane 5; second center plane 6; exhaust port 7; intake port 8; combustion chamber 9. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0022] At present, natural gas engines are mainly modified and matched based on the existing diesel engine platform, and one of the key components, the cylinder head 1, usually retains the structure of the original diesel engine's vortex cylinder head 1. This design method aims to utilize mature diesel engine technology to reduce development costs and time; but this means that the airway also retains the vortex airway, which has low turbulent kinetic energy in the cylinder during ignition, and large-scale vortices will increase the tendency of knocking, which is not conducive to improving thermal efficiency.

[0023] Natural gas engines are spark-ignited, just like gasoline engines, and gasoline engines all have dome tumble airways. Tumble is a rotational motion perpendicular to the cylinder axis. This motion is crushed by the piston at the top dead center and is highly unstable, but it can increase the turbulent kinetic energy in the cylinder and help improve the combustion process. However, there are problems with the use of dome tumble airways. The dome tumble airway causes the valve to be tilted. After the valve is tilted, the engine cannot be remodeled based on the diesel engine. At the same time, a new cylinder head processing line and engine assembly line need to be built, and the initial investment in industrialization is huge. In addition, the tumble generated by the dome is relatively large, and strong tumble may lead to increased cycle changes, affecting the stability and durability of the engine.

[0024] In order to solve the technical problem that the turbine air duct or tumble air duct used in the cylinder head 1 in the prior art affects the performance of the gas engine, the present invention provides an arc-shaped inclined cross-cylinder straight air duct cylinder head, which can solve the technical problem that the turbine air duct or tumble air duct used in the prior art affects the performance of the gas engine.

[0025] It should be noted that the arc-shaped inclined cross-cylinder straight-air duct cylinder head described in the present invention is used for but not limited to gas engines, etc. For the convenience of explanation, in the present invention, only the arc-shaped inclined cross-cylinder straight-air duct cylinder head applied to a gas engine is used as an example for explanation, and the principle of applying the arc-shaped inclined cross-cylinder straight-air duct cylinder head to other types of equipment is essentially the same as the principle applied to the gas engine, which will not be repeated here.

[0026] See also Figure 1 , Figure 1 The present invention is a schematic diagram of the structure of an arc-shaped inclined cross-cylinder straight-air channel cylinder head in one embodiment of the present invention. The arc-shaped inclined cross-cylinder straight-air channel cylinder head comprises a flat-top cylinder head 1, two exhaust channels 2, a first intake channel 3 and a second intake channel 4. The intake ends of the two exhaust channels 2 are connected to the cylinder head 1 and are arranged on one side of the cylinder head 1; the first intake channel 3 and the second intake channel 4 are tumble flow channels, and the outlet ends are connected to the cylinder head 1. A first center plane 5 passing through the axis of the cylinder head 1 is formed between the first intake channel 3, the second intake channel 4 and the two exhaust channels 2, and the angles between the extended lines of the projections of the first intake channel 3 and the second intake channel 4 on the top surface of the cylinder head 1 and the first center plane 5 are both less than 90°.

[0027] Specifically, when the mixed gas enters the cylinder, the mixed gas first enters the intake manifold, and then enters the first intake passage 3 and the second intake passage 4 through the intake manifold. The airflow mainly organizes the flow field in the first intake passage 3 and the second intake passage 4. Since the first intake passage 3 and the second intake passage 4 adopt tumble flow passages, after the mixed gas enters the cylinder through the first intake passage 3 and the second intake passage 4, the airflow will form a rotational motion in the vertical direction, namely, tumble flow; since the angle between the extension line of the projection of the first intake passage 3 and the second intake passage 4 on the top surface of the cylinder head 1 and the first center plane 5 is less than 90°, the extension line of the projection of the first intake passage 3 and the second intake passage 4 on the top surface of the cylinder head 1 is inclined to the first center plane 5, and after the mixed gas enters the cylinder based on the inclined first intake passage 3 and the second intake passage 4, the airflow will form a rotational motion in the horizontal direction, namely, vortex flow; therefore, after the mixed gas enters the cylinder, it has both tumble flow and vortex flow, such as Figure 5 As shown in FIG. 1 , the mixed gas has both turbine and tumble in the cylinder. Through simulation, it is found that, in fact, the airflow of the mixed gas in the cylinder will form a rotating motion inclined in the vertical direction, and the tumble and vortex will enhance each other, which is reflected in the relative improvement of the tumble ratio and the vortex ratio. Figure 6 As shown in Figure 2, a tumble flow in the cylinder in the Y direction (perpendicular to the intake and exhaust direction) can be seen. Figure 7 As shown in the figure, a turbine can be clearly seen in the cylinder. On the other hand, a certain degree of swirl can accelerate combustion in the late stage of combustion, thereby shortening the ignition delay period with tumble flow, reducing the combustion duration with swirl flow, accelerating the combustion speed in an all-round way, making full use of the compression energy before the top dead center, and effectively improving the thermal efficiency; at the same time, the combination of tumble flow and turbine can reduce the impact of a single tumble flow or a turbine that is too large on the performance of the gas engine.

[0028] Moreover, the cylinder head 1 in the present application adopts a flat-top cylinder head 1. Under the condition of non-dome design, the arc-shaped inclined cross-cylinder straight air duct cylinder head increases the turbulent kinetic energy near the spark plug electrode. After the spark plug is ignited, the fire core diffuses outward at the spark plug electrode position, and the flame can quickly fill the combustion chamber 9 with the tumble and vortex movement, thereby accelerating the combustion speed and improving the thermal efficiency of the whole machine.

[0029] The design of matching the first air intake passage 3 and the second air intake passage 4 with the dual exhaust passage 2 is beneficial to smooth airflow organization, to increase the tumble ratio, to fully utilize turbulent kinetic energy, and to accelerate the combustion speed.

[0030] The arc-shaped inclined cross-cylinder straight airway cylinder head of the present invention adopts a flat-top cylinder head 1, which can be used in the production and assembly line of the diesel engine cylinder head 1, with small initial manufacturing investment, and can make full use of existing resources without large-scale investment. Keeping the boundary conditions of the cylinder head 1 unchanged, by optimizing the structure and layout of the first intake channel 3 and the second intake channel 4, tumble and vortex can be generated in the cylinder at the same time, thereby increasing the turbulent kinetic energy in the cylinder, accelerating the flame propagation speed, accelerating combustion, and thus improving the thermal efficiency of the engine.

[0031] In order to form a tumble flow in the cylinder, the first intake passage 3 and the second intake passage 4 need to be set as tumble flow passages. In order to form the tumble flow passages, specifically, Figure 3 As shown, in some embodiments, the first intake duct 3 and the second intake duct 4 both have a first inclined air duct, an arc guide air duct and a second inclined air duct connected in sequence along the direction close to the cylinder head 1, and the slope of the first inclined air duct is smaller than the slope of the second inclined air duct.

[0032] After the mixed gas enters the first intake duct 3 and the second intake duct 4, it first enters the first inclined air duct with a small angle, and then is smoothly transitioned to the second inclined air duct with a large angle through the arc guide air duct. The mixed gas enters the cylinder through the lower part of the first intake duct 3 and the second intake duct 4 that tangent to the large-angle wall of the cylinder. Since the extension line of the projection of the first intake duct 3 and the second intake duct 4 on the top surface of the cylinder head 1 is inclined relative to the first center plane 5, the mixed gas presents tumble motion and turbine motion in the cylinder, and the tumble motion and turbine motion act together in the cylinder.

[0033] By configuring the first air intake duct 3 and the second air intake duct 4 to be a first inclined air intake duct, an arc guide air intake duct and a second inclined air intake duct which are connected in sequence, and the slope of the first inclined air intake duct is smaller than the slope of the second inclined air intake duct, and directly adopting the second inclined air intake duct with a large slope is avoided, the height dimensions of the first air intake duct 3 and the second air intake duct 4 can be reduced, so that the dimensions of the first air intake duct 3 and the second air intake duct 4 can be reduced while realizing tumble intake; at the same time, a two-stage progressive intake is adopted, so that the mixed gas changes the intake angle in a progressive manner, reduces the intake damping, and allows the mixed gas to enter the cylinder more easily.

[0034] In order to form the first inclined airway, the arc guide airway and the second inclined airway in the first air intake duct 3 and the second air intake duct 4, specifically, as Figure 3As shown, in some embodiments thereof, there is a second center plane 6 passing through the axis of the cylinder head 1 between the first intake channel 3 and the second intake channel 4, and in the projection of the second center plane 6, the first intake channel 3 and the second intake channel 4 have a first straight line segment, a first arc segment and a second straight line segment connected in sequence on one side close to the cylinder head 1, the angle θ2 between the first straight line segment and the top surface of the cylinder head 1 is in the range of 0° to 15°, the angle R1 of the first arc segment is in the range of 80 mm to 100 mm, and the angle θ1 between the second straight line segment and the top surface of the cylinder head 1 is in the range of 40° to 60°; The first air intake passage 3 and the second air intake passage 4 have a third straight line segment, a second arc segment and a fourth straight line segment connected in sequence on the side away from the cylinder head 1. The angle θ4 between the third straight line segment and the top surface of the cylinder head 1 is in the range of 20° to 40°, the angle R2 of the second arc segment is in the range of 80 mm to 100 mm, and the angle θ3 between the fourth straight line segment and the top surface of the cylinder head 1 is in the range of 30° to 50°.

[0035] Among them, the area of ​​the inner wall between the first straight line segment and the third straight line segment is the first inclined airway, the area of ​​the inner wall between the first arc segment and the second arc segment is the arc guide airway, and the area of ​​the inner wall between the second straight line segment and the fourth straight line segment is the second inclined airway.

[0036] Specifically, Figure 3 As shown, in one embodiment, the angle θ2 between the first straight line segment and the top surface of the cylinder head 1 is 7.5°, the angle R1 of the first arc segment is in the range of 90 mm, and the angle θ1 between the second straight line segment and the top surface of the cylinder head 1 is in the range of 50°; the side of the intake duct away from the cylinder head 1 has a third straight line segment, a second arc segment and a fourth straight line segment connected to each other, the angle θ4 between the third straight line segment and the top surface of the cylinder head 1 is in the range of 30°, the angle R2 of the second arc segment is in the range of 90 mm, and the angle θ3 between the fourth straight line segment and the top surface of the cylinder head 1 is in the range of 40°.

[0037] The first intake port 3, the second intake port 4 and the two exhaust ports 2 formed with the above-mentioned dimensions can simultaneously form a tumble flow and a turbine in the cylinder.

[0038] It should be understood that the angle between the extended line of the projection of the first intake passage 3 and the second intake passage 4 on the top surface of the cylinder head 1 and the first center plane 5 is appropriately reduced, and the larger the turbine formed in the cylinder, the larger the angle, and the smaller the turbine formed in the cylinder. For this reason, Figure 1 and Figure 2 As shown, in some of the embodiments, the angle between the extended line of the projection of the first intake passage 3 and the second intake passage 4 on the top surface of the cylinder head 1 and the first center plane 5 is 45° to 55°.

[0039] Within this range, a turbine of appropriate size can be formed, and at the same time, the intake passages in the adjacent arc-shaped inclined cross-cylinder straight air passage cylinder head can have appropriate space for arrangement.

[0040] Specifically, Figure 1 and Figure 2 As shown, in one of the embodiments, the angle between the extended line of the projection of the first intake passage 3 and the second intake passage 4 on the top surface of the cylinder head 1 and the first center plane 5 is 50°.

[0041] In this embodiment, after weighing the arrangement of the intake passages in the cylinder head of the adjacent arc-shaped inclined cross-cylinder straight air passages, the influence of the angle range on the turbine in the cylinder, and the influence of the angle on the intake damping and intake flow, the test results show that the best angle between the extension line of the projection of the first intake passage 3 and the second intake passage 4 on the top surface of the cylinder head 1 and the first center plane 5 is 50°. At this angle, a stronger turbine can be obtained compared with the existing cylinder head 1. Figure 6 As shown in Figure 1, a tumble flow in the Y direction (perpendicular to the intake and exhaust directions) can be seen in the cylinder, as shown in Figure 1. Figure 7 As shown, a turbine is clearly visible inside the cylinder.

[0042] like Figure 1 and Figure 2 As shown, in some embodiments, the two exhaust passages 2 are symmetrically distributed along the second center plane 6, the distance between the two exhaust passages 2 gradually decreases in the direction away from the cylinder head 1, and the outlet ends of the two exhaust passages 2 share an outlet port.

[0043] The two exhaust passages 2 gradually approach each other in a direction away from the cylinder head 1. The two exhaust passages 2 can provide for the discharge of tumble flow while helping to smoothly discharge the vortex in the cylinder. Cooperating with the two intake passages, the tumble flow field in the cylinder can be effectively assembled. Since the two exhaust passages 2 gradually approach each other in a direction away from the cylinder, the two exhaust passages 2 gradually approach each other in a direction away from the cylinder. In order to arrange the two exhaust passages 2 in a limited space, in this embodiment, the two exhaust passages 2 share an exhaust port 7, so that the two exhaust passages 2 can be close to each other, so that the two exhaust passages 2 can be arranged at a set angle as much as possible. At the same time, sharing an exhaust port 7 reduces the number of interfaces for docking with subsequent equipment, increases the area of ​​the exhaust port 7, can increase the exhaust flow rate, reduce the exhaust resistance, and effectively promote cylinder emptying.

[0044] Since the two exhaust passages 2 share one exhaust port 7, in order to guide the exhaust gas to smoothly enter the exhaust port 7 of the exhaust passage 2 from the intake end of the exhaust passage 2, in one embodiment, the projection of the exhaust passage 2 on the top surface of the cylinder head 1 is arc-shaped.

[0045] By setting the projection of the exhaust duct 2 on the top surface of the cylinder head 1 to be arc-shaped, the exhaust duct 2 can be discharged from the cylinder in an arc-shaped manner. The arc-shaped exhaust duct 2 can guide the mixed gas to be discharged from the exhaust duct 2 in an arc-shaped manner and discharge from the cylinder from the exhaust port 7 of the exhaust duct 2, thereby avoiding corners in the intake path and reducing exhaust damping.

[0046] In order to reduce the exhaust damping between the two exhaust ducts 2, as Figure 1 and Figure 2 As shown, in some of the embodiments, the side walls of the gas outlet ends of the two exhaust passages 2 are provided with first openings connecting the two exhaust passages 2 .

[0047] In this embodiment, the flow rates of the two exhaust gases can be balanced, reducing the overall exhaust back pressure, and helping to expel the burned exhaust gas from the cylinder more quickly. The reduced exhaust resistance allows the engine to run more smoothly under high performance conditions, thereby increasing the maximum power output.

[0048] Since, the smaller the angle between the first intake duct 3 and the second intake duct 4 relative to the first center plane 5, it is beneficial to increase the intake swirl. However, the smaller the angle, the smaller the spacing between the intake ducts in the cylinder head of adjacent arc-shaped inclined cross-cylinder straight ducts will be. The intake ducts in the cylinder head of adjacent arc-shaped inclined cross-cylinder straight ducts will limit the layout of the inclination angles of the first intake duct 3 and the second intake duct 4. For this reason, in some embodiments, the projections of the first intake duct 3 and the second intake duct 4 on the top surface of the cylinder head 1 are arc-shaped, and gradually deviate from the first center plane 5 in the direction away from the cylinder head 1.

[0049] Through the above arrangement, while reducing the angle between the extended line of the projection of the first intake passage 3 and the second intake passage 4 on the top surface of the cylinder head 1 and the first center plane 5, the first intake passage 3 and the second intake passage 4 are curved in an arc shape in a direction deviating from the first center plane, thereby reducing the angle between the first intake passage 3 and the second intake passage 4 and the first center plane 5, and at the same time increasing the distance between the intake passages in the cylinder head of adjacent arc-shaped inclined cross-cylinder straight passages, so as to reduce the angle between the first intake passage 3 and the second intake passage 4 and the first center plane 5 as much as possible within a limited space; by setting the projection of the first intake passage 3 and the second intake passage 4 on the top surface of the cylinder head 1 to be arc-shaped, the arc-shaped first intake passage 3 and the second intake passage 4 can guide the mixed gas to enter from the intake port 8 of the first intake passage 3 and the second intake passage 4 in an arc-shaped manner, and enter the cylinder from the exhaust port 7 of the first intake passage 3 and the second intake passage 4, thereby avoiding the existence of corners in the intake path and reducing the intake damping.

[0050] In a second aspect, the present invention further provides a gas engine, comprising the arc-shaped inclined cross-cylinder straight airway cylinder head as claimed in the claim. Since the engine adopts the arc-shaped inclined cross-cylinder straight airway cylinder head in the above embodiment, the technical effect of the gas engine can refer to the above embodiment.

[0051] It should be understood that the smaller the angle between the extension line of the projection of the first intake duct 3 and the second intake duct 4 on the top surface of the cylinder head 1 and the first center plane 5, the more inclined the first intake duct 3 and the second intake duct 4 will be. The increase in inclination will cause interference between the two adjacent arc-shaped inclined cross-cylinder straight intake ducts in the cylinder head. In addition, the turning angle of the intake manifold entering the first intake duct 3 and the second intake duct 4 will also be larger, and the intake damping will also be greater. For this reason, Figure 2 As shown, in some of the embodiments, there are multiple arc-shaped inclined cross-cylinder straight air duct cylinder heads in the gas engine, and two adjacent second intake ducts 4 in the multiple arc-shaped inclined cross-cylinder straight air duct cylinder heads share an intake port 8, and the side walls of the intake ends of the two adjacent second intake ducts 4 are provided with second openings connecting the two second intake ducts 4.

[0052] In this embodiment, two adjacent second intake passages 4 in the multiple arc-shaped inclined cross-cylinder straight-passage cylinder heads share an intake port 8, so that the first intake passage 3 and the second intake passage 4 are inclined as much as possible, while avoiding mutual interference between the intake passages in the adjacent arc-shaped inclined cross-cylinder straight-passage cylinder heads. At the same time, two adjacent second intake passages 4 in the multiple arc-shaped inclined cross-cylinder straight-passage cylinder heads share an intake port 8, so that the area of ​​the intake port 8 of the second intake passage 4 is increased, so that the area of ​​the connection between the intake manifold and the second intake passage 4 is increased, the flow coefficient is increased, and it is beneficial to increase the intake flow rate. Through more intake, it is ensured that the fuel gas and the air are fully mixed, supporting more complete combustion, thereby releasing more energy. In addition, the increase in intake flow rate also avoids incomplete combustion as much as possible, reduces harmful substances in emissions, and optimizes emission control. At the same time, using one air intake port 8 can reduce the number of interfaces of the air intake port 8 and reduce the difficulty of assembly and assembly; by setting a second opening, the flow rates of the two intake air can be balanced, reducing the overall intake resistance, helping to pass the mixed gas into the cylinder faster, and helping to increase the power of the engine. At the same time, the optimization of the intake system makes the gas engine respond more quickly to the pedal, especially during acceleration.

[0053] like Figure 3 As shown, in some embodiments, the gas engine further comprises a combustion chamber 9 matched with the cylinder head 1, wherein the combustion chamber 9 is cylindrical on one side close to the cylinder head 1, and the inner wall and outer wall of the combustion chamber 9 away from the cylinder head 1 are spherical.

[0054] Through the above arrangement, when the mixed gas flows through the spherical surface at the bottom of the combustion chamber 9, it can flow along the spherical surface at the bottom of the combustion chamber 9 to form a tumble flow in the combustion chamber 9, and can cooperate with the arc-shaped center-cross-cylinder straight air channel cylinder head 1 to strengthen the tumble flow in the cylinder during the intake and compression strokes, thereby increasing the combustion speed and reducing fuel consumption.

[0055] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0056] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0057] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific conditions.

[0058] In the description of this specification, specific features, structures, materials or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

[0059] The specific implementation of the present invention described above does not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. An arc-shaped inclined cross-cylinder straight airway cylinder head, characterized in that: include: Flat top cylinder head; Two exhaust passages, the air inlet ends of the two exhaust passages are connected to the cylinder head and are arranged on one side of the cylinder head; The first intake duct and the second intake duct are tumble flow ducts, and the outlet ends are connected to the cylinder head. A first center plane passing through the axis of the cylinder head is formed between the first intake duct, the second intake duct and the two exhaust ducts. The angles between the extended lines of the projections of the first intake duct and the second intake duct on the top surface of the cylinder head and the first center plane are both less than 90°.

2. The cylinder head with an arc-shaped inclined cross-cylinder straight airway according to claim 1 is characterized in that: The first intake passage and the second intake passage both have a first inclined air passage, an arc guide air passage and a second inclined air passage that are sequentially connected along a direction approaching the cylinder head, and the slope of the first inclined air passage is smaller than the slope of the second inclined air passage.

3. The straight channel cylinder head according to claim 2, characterized in that: A second center plane passing through the axis of the cylinder head is provided between the first intake passage and the second intake passage. In the projection of the first intake passage and the second intake passage on the second center plane, the first intake passage and the second intake passage have a first straight line segment, a first arc segment and a second straight line segment connected in sequence on one side close to the cylinder head. The angle θ2 between the first straight line segment and the top surface of the cylinder head is in the range of 0° to 15°, the angle R1 of the first arc segment is in the range of 80 mm to 100 mm, and the angle θ1 between the second straight line segment and the top surface of the cylinder head is in the range of 40° to 60°. The first air intake passage and the second air intake passage have a third straight line segment, a second arc segment and a fourth straight line segment connected in sequence on the side away from the cylinder head. The angle θ4 between the third straight line segment and the top surface of the cylinder head is in the range of 20° to 40°, the angle R2 of the second arc segment is in the range of 80 mm to 100 mm, and the angle θ3 between the fourth straight line segment and the top surface of the cylinder head is in the range of 30° to 50°.

4. The straight channel cylinder head according to claim 1, characterized in that: The angle between the extended line of the projection of the first intake passage and the second intake passage on the top surface of the cylinder head and the first center plane is in the range of 45° to 55°.

5. The cylinder head with an arc-shaped inclined cross-cylinder straight airway according to claim 3 is characterized in that: The two exhaust passages are symmetrically distributed along the second center plane, the distance between the two exhaust passages gradually decreases in a direction away from the cylinder head, and the outlet ends of the two exhaust passages share an outlet port.

6. The cylinder head with an arc-shaped inclined cross-cylinder straight airway according to claim 5 is characterized in that: The side walls of the air outlet ends of the two exhaust passages are provided with a first opening communicating with the two exhaust passages.

7. The cylinder head with an arc-shaped inclined cross-cylinder straight airway according to claim 1, characterized in that: The projections of the first air intake passage and the second air intake passage on the top surface of the cylinder head are arc-shaped and gradually deviate from the first center plane in a direction away from the cylinder head.

8. A gas engine, characterized in that: It comprises a cylinder head with an arc-shaped inclined cross-cylinder straight air passage as described in any one of claims 1-7.

9. The gas engine according to claim 8, characterized in that: The gas engine has a plurality of cylinder heads with arc-shaped inclined cross-cylinder straight air passages, and two adjacent second air intake passages in the plurality of cylinder heads with arc-shaped inclined cross-cylinder straight air passages share an air intake port, and the side walls of the air intake ends of the two adjacent second air intake passages are provided with a second opening connecting the two second air intake passages.

10. The gas engine according to claim 8, characterized in that: It also includes a combustion chamber matched with the cylinder head. The combustion chamber is cylindrical on one side close to the cylinder head, and the inner wall and outer wall of the combustion chamber away from the cylinder head are spherical.

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