Integrated exhaust manifold and engine
By optimizing the central streamline design of the integrated exhaust manifold, the problems of poor exhaust flow and uneven gas distribution are solved, resulting in more efficient exhaust performance and reduced fuel consumption.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- GREAT WALL MOTOR CO LTD
- Filing Date
- 2022-05-24
- Publication Date
- 2026-07-21
AI Technical Summary
Existing integrated exhaust manifolds do not adequately consider gas flow in their design, resulting in poor exhaust flow and uneven gas distribution, leading to poor exhaust performance.
An integrated exhaust manifold was designed, comprising an intake end, an exhaust end, and multiple exhaust branch pipes. The exhaust branch pipes include first and second manifolds, and the central streamline consists of straight segments and arc segments connected by smooth transitions to optimize the gas flow path and ensure smooth gas flow along the central streamline.
The integrated exhaust manifold improves exhaust efficiency, reduces gas flow and energy loss along the path, ensures the energy utilization and stable operation of the turbocharger turbine, and reduces fuel consumption.
Smart Images
Figure CN117145622B_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of vehicle technology, specifically relating to an integrated exhaust manifold and engine. Background Technology
[0002] Currently, vehicle emission regulations are becoming increasingly stringent, and competition in the automotive market is intensifying. To meet emission requirements and reduce engine production costs, integrated exhaust manifold technology has emerged.
[0003] In existing technologies, compared with the previous method of simply relying on enriching the air-fuel mixture to limit exhaust temperature, integrated exhaust manifolds can reduce fuel consumption by 10% to 30% in the high-speed, high-load operating range of the engine, which is one of the measures to reduce carbon emissions from the engine.
[0004] However, current integrated exhaust manifold designs only consider the exhaust function and do not pay much attention to the actual flow of gas within the integrated exhaust manifold. As a result, integrated exhaust manifolds suffer from problems such as poor exhaust flow and uneven gas distribution, leading to poor exhaust performance. Summary of the Invention
[0005] The purpose of this application embodiment is to provide an integrated exhaust manifold, including an intake end, an outlet end, and multiple exhaust branch pipes. The intake end and the outlet end are connected by multiple exhaust branch pipes. Each exhaust branch pipe includes multiple manifolds. The exhaust branch pipe includes a first exhaust branch pipe, which is located at the position farthest from the outlet end. The first exhaust branch pipe includes a first manifold and a second manifold. The first manifold has a first central streamline, and the second manifold has a second central streamline. The first central streamline and the second central streamline converge at a position near the outlet end to form a third central streamline, which extends towards the outlet end. The first central streamline, the second central streamline, and the third central streamline all include at least one of a straight segment and a circular arc segment, and the straight segment and the circular arc segment are smoothly connected.
[0006] Optionally, multiple exhaust manifolds are configured to correspond one-to-one with multiple cylinders. The line connecting the centers of the multiple cylinders is defined as the center line, and the plane parallel to the outlet end face where the center line is located is defined as the longitudinal plane of the cylinder center. The outlet end face is defined as the plane where the outlet port is located, and the outlet end face is perpendicular to the horizontal plane.
[0007] Each manifold is equipped with a valve guide. The plane containing the central axes of multiple valve guides is defined as the valve guide center plane. The angle between the longitudinal plane of the cylinder center and the valve guide center plane is defined as b1, and satisfies 10°≤b1≤30°.
[0008] Optionally, the center distance between two adjacent cylinders is defined as D; the first central streamline extending from the intake end to the exhaust end includes, in sequence, a first arc segment, a first straight line segment, and a second arc segment.
[0009] The valve guide connected to the first manifold is the first valve guide. The plane perpendicular to the longitudinal plane of the cylinder center where the bottom of the cylinder head is located is defined as the bottom surface of the cylinder head. The angle between the projection of the central axis of the first valve guide on the bottom surface of the cylinder head and the projection of the tangent of the first arc segment on the bottom surface of the cylinder head is defined as b2, and satisfies 0.3b1≤b2≤0.6b1. The tangent of the first arc segment is the tangent passing through the end point of the first arc segment near the intake end.
[0010] The radius of the first arc segment is r1, and it satisfies 0.4D≤r1≤0.7D.
[0011] Optionally, the angle between the projection of the central axis of the first valve guide onto the bottom surface of the cylinder head and the projection of the first straight line segment onto the bottom surface of the cylinder head is defined as b3, and satisfies 3b2≤b3≤3b1.
[0012] Optionally, the radius of the second arc segment is r2, and r1≤r2≤2r1.
[0013] Optionally, in the direction extending from the intake end to the exhaust end, the third central streamline successively includes a second straight line segment and a fifth arc segment, the fifth arc segment extending to the exhaust end, and the angle between the projection of the cylinder center longitudinal plane on the bottom surface of the cylinder head and the projection of the second straight line segment on the bottom surface of the cylinder head is defined as a11, and satisfies 0.3b2≤a11≤0.6b2;
[0014] The radius of the fifth arc segment is r5, and r1≤r5≤r2.
[0015] Optionally, in the direction extending from the intake end to the exhaust end, the second central streamline successively includes a third arc segment and a fourth arc segment; the valve guide connected to the second manifold is the second valve guide, and the angle between the projection of the central axis of the second valve guide on the bottom surface of the cylinder head and the projection of the tangent of the third arc segment on the bottom surface of the cylinder head is defined as b4, and satisfies 0.5b2≤b4≤b2, and the tangent of the third arc segment is the tangent passing through the end point of the third arc segment near the intake end;
[0016] The radius of the third arc segment is r3, and r1≤r3≤r2; the radius of the fourth arc segment is r4, and r1≤r4≤r3.
[0017] Optionally, the plane perpendicular to the end face of the exhaust end where the center of the exhaust end is located is defined as the exhaust end center plane. The angle between the projection of the exhaust end center plane onto the bottom surface of the cylinder head and the projection of the extension line of the fifth arc segment near the end of the exhaust end onto the bottom surface of the cylinder head is defined as a12, and b2≤a12≤b1 is satisfied.
[0018] Optionally, the multiple exhaust manifolds may also include a second exhaust manifold and a third exhaust manifold arranged in sequence, with the third exhaust manifold located near the exhaust end.
[0019] This application also provides an engine including the integrated exhaust manifold as described above.
[0020] The technology described in this application solves the problem of poor exhaust performance of integrated exhaust manifolds and improves the exhaust effect of integrated exhaust manifolds. Attached Figure Description
[0021] Figure 1 This is a schematic diagram of the integrated exhaust manifold in an embodiment of this application;
[0022] Figure 2 This is a side view schematic diagram of the integrated exhaust manifold structure in an embodiment of this application;
[0023] Figure 3 This is a schematic diagram of the first central streamline in an embodiment of this application;
[0024] Figure 4 This is a schematic diagram of the second central streamline in an embodiment of this application;
[0025] Figure 5 This is a schematic diagram of the third central streamline in an embodiment of this application;
[0026] Figure 6 This is a schematic diagram of the gas flow rate from the exhaust duct in an embodiment of this application;
[0027] Figure 7 This is a schematic diagram showing the changing trend of the flow coefficient under valve lift in the embodiments of this application.
[0028] Explanation of reference numerals in the attached figures:
[0029] 10. Integrated exhaust manifold; 11. Intake end; 12. Exit end; 13. First manifold; 14. Second manifold; 15. First central streamline; 16. Second central streamline; 17. Third central streamline; 18. Cylinder; 19. Cylinder center longitudinal plane; 20. Valve guide center surface; 21. Central straight line; 151. First arc segment; 152. First straight segment; 153. Second arc segment; 161. Third arc segment; 162. Fourth arc segment; 171. Second straight segment; 172. Fifth arc segment; 121. Exit end face; 122. Exit end center surface; 23. Cylinder head bottom surface. Detailed Implementation
[0030] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0031] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.
[0032] The integrated exhaust manifold provided in this application will be described in detail below with reference to the accompanying drawings, through specific embodiments and application scenarios.
[0033] See Figures 1 to 7 The embodiments of this application provide an integrated exhaust manifold 10, including an intake end 11, an outlet end 12 and a plurality of exhaust branch pipes. The intake end 11 and the outlet end 12 are connected by the plurality of exhaust branch pipes. Each exhaust branch pipe includes a plurality of manifolds. The exhaust branch pipe includes a first exhaust branch pipe, which is located at the position furthest from the outlet end 12. The first exhaust branch pipe includes a first manifold 13 and a second manifold 14.
[0034] The first manifold 13 has a first central streamline 15, and the second manifold 14 has a second central streamline 16. The first central streamline 15 and the second central streamline 16 converge at a position near the outlet end 12 to form a third central streamline 17, which extends toward the outlet end 12.
[0035] The first central streamline 15, the second central streamline 16, and the third central streamline 17 each include at least one of a straight line segment and a circular arc segment, with a smooth transition between the straight line segment and the circular arc segment.
[0036] In this embodiment, the integrated exhaust manifold 10 includes an intake end 11, an outlet end 12, and multiple exhaust branch pipes. The intake end 11, the outlet end 12, and the multiple exhaust branch pipes are connected, and the multiple exhaust branch pipes connect the intake end 11 and the outlet end 12. Gas flows into the integrated exhaust manifold 10 from the intake end 11 and flows along a central streamline in the integrated exhaust manifold 10. The multiple exhaust branch pipes include a first exhaust branch pipe farthest from the outlet end 12. The first exhaust branch pipe includes a first manifold 13 and a second manifold 14. The first manifold 13 has a first central streamline 15, and the second manifold 14 has a second central streamline 16. The first central streamline 15 and the second central streamline 16 converge near the outlet end 12 to form a third central streamline 17, and the third central streamline 17 extends towards the outlet end 12. Finally, the gas flows out from the outlet end 12. The temperature of the gas flowing out from the outlet 12 can be controlled within the acceptable temperature limits of the exhaust system components. The integrated exhaust manifold 10 can reduce fuel consumption by 10% to 30% in the high-speed, high-load operating range of the engine, which is one of the effective measures to reduce carbon emissions from the engine. After flowing into the intake end 11, the gas can flow in the first exhaust branch pipe. The first manifold 13 and the second manifold 14 provide channels for gas flow. The gas can flow along the first central streamline 15 of the first manifold 13, and at the same time, the gas can flow along the second central streamline 16 of the second manifold 14. The central streamlines in the manifold can guide the gas flow, making the gas flow smoother. The first central streamline 15, the second central streamline 16, and the third central streamline 17 all include at least one of a straight line segment and a circular arc segment, and the straight line segment and the circular arc segment are smoothly connected. In this embodiment, the interconnected straight segments and arc segments can guide the direction of gas flow. By setting the straight segments and arc segments, the gas flow in the integrated exhaust manifold 10 can be made smoother, reducing the loss of flow along the flow path of the gas during the flow along the central streamline, which has the beneficial effect of improving the exhaust performance of the integrated exhaust manifold 10.
[0037] It should be noted that the smooth transition between the straight line segment and the arc segment allows the first central streamline 15, the second central streamline 16, and the third central streamline 17 to connect and form a smooth central streamline. The smooth central streamline allows the gas to flow along the central streamline while preventing significant energy loss due to insufficient shape optimization of the first central streamline 15, the second central streamline 16, and the third central streamline 17 during the gas flow. This has the beneficial effect of reducing the energy loss of the gas along the flow path.
[0038] It should also be noted that the rational design of the center streamline and contour of the integrated exhaust manifold 10 can effectively guide the gas flow, making the gas flow resistance fluctuation smaller, effectively preventing gas flow separation, and ensuring the energy utilization rate and continuous stable operation of the turbocharger turbine.
[0039] It should also be noted that the first central streamline 15 may include straight line segments and arc segments, wherein the order of the straight line segments and arc segments can be arbitrarily combined according to actual conditions, and this embodiment does not impose any limitation on this. The second central streamline 16 may be a combination of arc segments and arc segments, or a combination of straight line segments and arc segments, wherein the order of the straight line segments and arc segments can be arbitrarily combined according to actual conditions, and this embodiment does not impose any limitation on this. The third central streamline 17 may include straight line segments and arc segments, wherein the order of the straight line segments and arc segments can be arbitrarily combined according to actual conditions, and this embodiment does not impose any limitation on this.
[0040] Optionally, see Figures 1 to 2 In this embodiment, multiple exhaust manifolds are correspondingly arranged with multiple cylinders 18. The line connecting the cylinder centers of the multiple cylinders 18 is defined as the central straight line 21. The plane parallel to the outlet end face 121 where the central straight line 21 is located is defined as the cylinder center longitudinal plane 19. The outlet end face 121 is defined as the plane where the port of the outlet end 12 is located, and the outlet end face 121 is perpendicular to the horizontal plane. A valve guide is correspondingly arranged on each manifold. The plane where the central axis of the multiple valve guides is located is defined as the valve guide center plane 20. The angle between the cylinder center longitudinal plane 19 and the valve guide center plane 20 is defined as b1, and satisfies 10°≤b1≤30°.
[0041] In this embodiment, multiple cylinders 18 and multiple exhaust manifolds are one-to-one correspondences and connected. The intake end 11 is used to guide the gas discharged from the cylinders 18 into the integrated exhaust manifold 10. The multiple cylinders 18 include a first cylinder corresponding to a first exhaust manifold. The first exhaust manifold includes a first manifold 13 and a second manifold 14. Therefore, the first manifold 13 and the second manifold 14 are also corresponding to the first cylinders, thus allowing for faster guidance of the gas discharged from the first cylinders into the integrated exhaust manifold 10, improving the efficiency of guiding the gas discharged from the cylinders 18 into the integrated exhaust manifold 10. The line connecting the centers of the multiple cylinders 18 is defined as the center line 21, and the plane parallel to the outlet end face 121 containing the center line 21 is defined as the cylinder center longitudinal plane 19. The outlet end face 121 is the plane containing the outlet end 12 port, and the outlet end face 121 is perpendicular to the horizontal plane. In practical applications, every manifold is equipped with a valve guide, and every valve guide has a central axis, such as... Figure 2As shown, the plane containing the central axes of multiple valve guides is defined as the valve guide center plane 20, and the angle between the cylinder center longitudinal plane 19 and the valve guide center plane 20 is defined as b1, satisfying 10°≤b1≤30°. By rationally setting the above angle, the valve disc conical structure can be effectively utilized to guide the gas flow, improve the gas flow direction from cylinder 18 to the integrated exhaust manifold 10, and facilitate better entry of the gas discharged from cylinder 18 into the integrated exhaust manifold 10. This has the beneficial effect of guiding gas flow and facilitating better exhaust of gas from cylinder 18 into the combustion chamber of cylinder 18. It should be noted that b1 can preferably be 18° or 20°.
[0042] It should also be noted that the gas in cylinder 18 enters the integrated exhaust manifold 10 through the intake end 11, exits through the outlet end 12, and enters the turbocharger turbine flow channel. As the gas flows through the integrated exhaust manifold 10, it flows along the central streamline. Within the defined contour of the integrated exhaust manifold 10, the gas flow is guided, and the flow resistance fluctuations are small, effectively preventing gas flow separation. This ensures that when the gas exits the integrated exhaust manifold 10 and enters the turbocharger turbine, the energy utilization rate and continuous stable operation of the turbocharger turbine are guaranteed.
[0043] Optionally, see Figures 1 to 3 In this embodiment, the center distance between two adjacent cylinders 18 is defined as D; the first central streamline 15 extends from the intake end 11 to the outlet end 12, and sequentially includes a first arc segment 151, a first straight segment 152, and a second arc segment 153; the valve guide connected to the first manifold 13 is the first valve guide; the plane perpendicular to the longitudinal plane 19 of the cylinder center where the bottom of the cylinder head is located is defined as the bottom surface 23 of the cylinder head; the angle between the projection of the central axis of the first valve guide on the bottom surface 23 of the cylinder head and the projection of the tangent of the first arc segment 151 on the bottom surface 23 of the cylinder head is defined as b2, and satisfies 0.3b1≤b2≤0.6b1; the tangent of the first arc segment 151 is the tangent passing through the end point of the first arc segment 151 near the intake end 11.
[0044] The radius of the first arc segment 151 is r1, and it satisfies 0.4D≤r1≤0.7D.
[0045] In this embodiment, the first central streamline 15 extends from the air inlet 11 to the air outlet 12, and sequentially includes a first arc segment 151, a first straight segment 152, and a second arc segment 153, and the first arc segment 151, the first straight segment 152, and the second arc segment 153 are smoothly connected. The first arc segment 151, the first straight segment 152, and the second arc segment 153 are connected to form the first central streamline 15. The first arc segment 151 is designed to better receive the gas discharged from the cylinder 18, reducing gas flow loss as the gas enters the integrated exhaust manifold 10 from the cylinder 18. The first straight segment 152 connects the first arc segment 151 and the second arc segment 153, allowing for better utilization of the energy of the gas flowing through it and effectively guiding the gas towards the second arc segment 153. The second arc segment 153 guides the gas flow, allowing it to flow along the first straight segment 152 and then along the second arc segment 153, ultimately guiding it towards the third central streamline 17. The first central streamline 15 ensures smoother gas flow and effectively reduces gas flow loss along the path.
[0046] It should be noted that each manifold is equipped with a valve guide. The valve guide connected to the first manifold 13 is called the first valve guide. The plane perpendicular to the longitudinal plane 19 of the cylinder center, where the bottom of the cylinder head is located, is defined as the bottom surface 23 of the cylinder head. The angle between the projection of the central axis of the first valve guide onto the bottom surface 23 of the cylinder head and the projection of the tangent of the first arc segment 151 onto the bottom surface 23 of the cylinder head is defined as b2, and satisfies 0.3b1≤b2≤0.6b1. The tangent of the first arc segment 151 is the tangent passing through the endpoint of the first arc segment 151 near the intake end 11. The angle between the projection of the central axis of the first valve guide onto the bottom surface 23 of the cylinder head and the projection of the tangent of the first arc segment 151 is defined as b2, satisfying 0.3b1≤b2≤0.6b1. The angle between the projection on surface 23 and the projection of the tangent of the first arc segment 151 onto the bottom surface 23 of the cylinder head can effectively guide the gas from the cylinder 18 to the direction of the first arc segment 151, facilitating better exhaust of the gas generated in the cylinder 18 into the integrated exhaust manifold 10, and then sequentially along the first arc segment 151, the first straight segment 152, and the second arc segment 153. This can effectively stabilize the gas flow, maintaining a flow pattern where the gas flows at a high speed in the center, driving the surrounding airflow. This has the beneficial effect of reducing the proportion of gas flow near the wall and minimizing energy loss caused by the rough wall.
[0047] It should also be noted that the center distance between two adjacent cylinders 18 is defined as D, and the radius of the first arc segment 151 is r1, satisfying 0.4D≤r1≤0.7D. In practical applications, the radius of the first arc segment 151 is adjusted accordingly based on the center distance D between two adjacent cylinders 18. This effectively avoids gas flow separation and abrupt changes as the gas flows from the intake end 11 to the first arc segment 151, resulting in smoother gas flow, reduced gas flow loss along the path, and better preservation of gas energy.
[0048] Optionally, in this embodiment of the application, the angle between the projection of the central axis of the first valve guide on the bottom surface 23 of the cylinder head and the projection of the first straight line segment 152 on the bottom surface 23 of the cylinder head is defined as b3, and satisfies 3b2≤b3≤3b1.
[0049] In this embodiment, by limiting the angle between the projection of the central axis of the first valve guide onto the bottom surface 23 of the cylinder head and the projection of the first straight segment 152 onto the bottom surface 23 of the cylinder head, the gas flow velocities near the upper and lower contour walls of the first manifold 13 are approximately the same. The gas flow velocity at the center of the first manifold 13 is relatively higher than that at the wall, and the higher-velocity gas is approximately symmetrically distributed with the first central streamline 15, so that the higher-velocity airflow region occupies more than 1 / 2 of the cross-section of the first manifold 13. In practical applications, the gas flow velocity in the integrated exhaust manifold 10 is generally between 20 m / s and 70 m / s. Within the above-defined range, the higher-velocity intermediate gas drives the flow of gas near the upper and lower contour walls of the first manifold 13, further improving the gas flow capacity in the first manifold 13.
[0050] It should be noted that the inner wall of the first manifold 13 can also be reduced to reduce interference with gas flow, reduce energy loss of the wall airflow, and effectively improve the utilization rate of exhaust energy.
[0051] Optionally, in this embodiment of the application, the radius of the second arc segment 153 is r2, and it satisfies r1≤r2≤2r1.
[0052] In this embodiment, the limitation of the radius of the second arc segment 153 can effectively guide the gas flow towards the outlet end 12. By guiding the gas flow, the flow direction of the gas in the integrated exhaust manifold 10 can be improved. At the same time, by limiting the radius of the second arc segment 153, the velocity separation caused by the gas changing its flow direction can also be reduced, thereby minimizing the collision of the flowing gas with the wall of the first manifold 13, thus retaining the energy of the gas to the maximum extent and having the beneficial effect of reducing gas energy loss.
[0053] Optionally, see Figures 1 to 3 ,as well as Figure 5 In this embodiment of the application, the third central streamline 17 extends from the intake end 11 to the exhaust end 12, and includes a second straight line segment 171 and a fifth arc segment 172 in sequence. The fifth arc segment 172 extends to the exhaust end 12. The angle between the projection of the cylinder center longitudinal plane 19 on the bottom surface 23 of the cylinder head and the projection of the second straight line segment 171 on the bottom surface 23 of the cylinder head is defined as a11, and satisfies 0.3b2≤a11≤0.6b2.
[0054] The radius of the fifth arc segment 172 is r5, and r1≤r5≤r2.
[0055] In this embodiment, the third central streamline 17 includes a second straight line segment 152 and a fifth arc segment 172. The angle between the projection of the cylinder center longitudinal plane 19 on the bottom surface 23 of the cylinder head and the projection of the second straight line segment 171 on the bottom surface 23 of the cylinder head is a11, and satisfies 0.3b2≤a11≤0.6b2. By limiting the angle of a11, the second straight line segment 171 extends at the above angle, which can effectively stabilize the flow of gas and keep the gas in the flow form of the central airflow driving the surrounding airflow. This can reduce the proportion of gas flow near the wall of the integrated exhaust manifold 10, so that the gas far away from the wall of the integrated exhaust manifold 10 has more gas energy, which has the beneficial effect of reducing the gas energy loss caused by the wall of the integrated exhaust manifold 10.
[0056] Furthermore, the radius of the fifth arc segment 172 is r5, and r1≤r5≤r2. By limiting the radius of the fifth arc segment 172, the direction of gas flow can be effectively guided, reducing gas flow separation and effectively preventing gas from flowing to other exhaust branches, forming reverse airflow vortices, and hindering the normal flow of gas. This allows the gas to flow from the fifth arc segment 172 to the outlet end 12, avoiding energy loss caused by the formation of reverse airflow vortices during gas flow. This has the beneficial effect of ensuring the gas energy intensity at the outlet end 12.
[0057] Optionally, see Figures 1 to 4In this embodiment, the second central streamline 16 extends from the intake end 11 to the outlet end 12, and sequentially includes a third arc segment 161 and a fourth arc segment 162. The valve guide connected to the second manifold 14 is a second valve guide. The angle between the projection of the central axis of the second valve guide onto the bottom surface 23 of the cylinder head and the projection of the tangent of the third arc segment 161 onto the bottom surface 23 of the cylinder head is defined as b4, and satisfies 0.5b2≤b4≤b2. The tangent of the third arc segment 161 is the tangent passing through the endpoint of the third arc segment near the intake end 11. The radius of the third arc segment 161 is r3, and satisfies r1≤r3≤r2. The radius of the fourth arc segment 162 is r4, and satisfies r1≤r4≤r3.
[0058] In this embodiment, the second central streamline 16 includes a third arc segment 161 and a fourth arc segment 162. The radius of the third arc segment is r3, and r1≤r3≤r2; the radius of the fourth arc segment 162 is r4, and r1≤r4≤r3. Furthermore, the angle between the projection of the central axis of the second valve guide onto the bottom surface 23 of the cylinder head and the projection of the tangent of the third arc segment 161 onto the bottom surface 23 of the cylinder head is b4, and 0.5b2≤b4≤b2. The second valve guide is a valve guide connected to the second manifold 14. In practical applications, by limiting the aforementioned included angle and the radius of the arc segment, the gas flows from the inlet end 11 to the second manifold 14 and along the second central streamline 16. The second central streamline 16 can effectively prevent gas flow direction separation and abrupt changes, making the airflow smoother, reducing the gas flow loss along the path, better ensuring the energy of the gas, and guiding the gas to flow towards the center of the second manifold 14, effectively increasing the gas velocity at the center of the second manifold 14.
[0059] Optionally, in this embodiment of the application, the plane perpendicular to the end face 121 of the exhaust end 12 where the center of the exhaust end 12 is located is defined as the exhaust end center plane 122. The angle between the projection of the exhaust end center plane 122 on the bottom surface 23 of the cylinder head and the projection of the extension line of the fifth arc segment 172 near the endpoint of the exhaust end 12 on the bottom surface 23 of the cylinder head is a12, and b2≤a12≤b1 is satisfied.
[0060] In this embodiment, the outlet center plane 122 is defined as the plane perpendicular to the outlet end face 121 where the center of the outlet 12 is located. The angle between the projection of the outlet center plane 122 on the cylinder head bottom surface 23 and the projection of the extension line of the fifth arc segment 172 near the end point of the outlet 12 on the cylinder head bottom surface 23 is α12. The setting that b2≤a12≤b1 can effectively guide the gas flow. That is, the extension direction of the fifth arc segment 172 is set away from the center of the outlet 12. This can effectively reduce the flow separation of gas and prevent the gas from flowing to other adjacent exhaust branches, forming a reverse airflow vortex, which would hinder the normal flow of gas. This has the beneficial effect of avoiding energy loss caused by the formation of a reverse airflow vortex in the integrated exhaust manifold 10 and ensuring the gas energy intensity of the outlet 12.
[0061] Optionally, in this embodiment of the application, the plurality of exhaust branches also include a second exhaust branch and a third exhaust branch arranged in sequence, with the exhaust end 12 located near the third exhaust branch.
[0062] In this embodiment, the second exhaust branch pipe is located near the first exhaust branch pipe, and the third exhaust branch pipe is located near the outlet end 12. In practical applications, the second and third exhaust branch pipes are also used to guide the airflow direction in the integrated exhaust manifold 10, guide the gas flow, and reduce gas flow separation. The second exhaust branch pipe may include two manifolds, and the third exhaust branch pipe may also include two manifolds. Furthermore, without affecting the spatial arrangement, the cross-sectional area of the exhaust manifolds can be adjusted to reduce pressure fluctuations in the gas in different exhaust branch pipes, improve the energy utilization rate of high-temperature exhaust gas, and improve the exhaust performance of the integrated exhaust manifold.
[0063] Optionally, in this embodiment of the application, an engine is provided, including the integrated exhaust manifold 10 as described above.
[0064] In this embodiment, the engine includes the integrated exhaust manifold 10 and the turbocharger turbine as described above. By optimizing the central streamline in the exhaust branch pipe, the gas flow in the exhaust manifold is guided. The optimized central streamline can adjust the gas velocity distribution and reduce gas flow separation. Optimizing the central streamline achieves the requirement of high gas flow capacity without affecting the spatial arrangement, reduces gas flow resistance, reduces pressure fluctuations in different pipelines, and improves the energy utilization rate of the gas. This results in improved exhaust performance of the integrated exhaust manifold 10, improved energy utilization and operational stability of the turbocharger turbine, reduced engine jerking caused by fluctuations in turbocharger operation due to differences in exhaust output from different cylinders, and improved engine power.
[0065] It should be noted that in practical applications, the cross-section of the integrated exhaust manifold 10 can be adjusted to a certain extent. With the combined effect of the optimized air section and manifold cross-section, the exhaust capacity of the integrated exhaust manifold 10 can be improved.
[0066] Furthermore, as mentioned above, the engine can be installed in a vehicle. In practical applications, vehicles equipped with the aforementioned engine can control exhaust temperature within acceptable temperature limits for downstream system components without enriching the air-fuel mixture, or with only a slight enrichment, during high-speed, high-load engine operation. Compared to the previous method of simply relying on enriching the air-fuel mixture to limit exhaust temperature, the integrated exhaust manifold 10 can reduce fuel consumption by 10% to 30% during high-speed, high-load engine operation, representing one of the measures to reduce engine carbon emissions. This has the beneficial effects of meeting vehicle emission requirements and reducing overall vehicle production costs.
[0067] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.
[0068] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.
Claims
1. An integrated exhaust manifold, said integrated exhaust manifold being integrated into the cylinder head of an engine, characterized in that, It includes an air inlet, an air outlet, and multiple exhaust branch pipes. The air inlet and the air outlet are connected by the multiple exhaust branch pipes. Each exhaust branch pipe includes multiple manifolds. Each exhaust branch pipe includes a first exhaust branch pipe, which is located at the position furthest from the air outlet. The first exhaust branch pipe includes a first manifold and a second manifold. The first manifold has a first central streamline, the second manifold has a second central streamline, the first central streamline and the second central streamline converge at a position near the outlet end to form a third central streamline, and the third central streamline extends toward the outlet end; The first central streamline, the second central streamline, and the third central streamline all include straight line segments and circular arc segments, and the straight line segments and the circular arc segments are smoothly connected. Multiple exhaust manifolds are configured in a one-to-one correspondence with multiple cylinders. The line connecting the centers of the multiple cylinders is defined as the central straight line. The plane parallel to the exhaust end face where the central straight line is located is defined as the longitudinal plane of the cylinder center. The exhaust end face is defined as the plane where the exhaust end port is located, and the exhaust end face is perpendicular to the horizontal plane. Each of the manifolds is provided with a valve guide. The plane containing the central axes of the multiple valve guides is defined as the valve guide center plane. The angle between the longitudinal plane of the cylinder center and the valve guide center plane is defined as b1, and satisfies 10°≤b1≤30°. The center distance between two adjacent cylinders is defined as D; the first central streamline extending from the air inlet to the air outlet includes, in sequence, a first arc segment, a first straight line segment, and a second arc segment. The valve guide connected to the first manifold is the first valve guide. The plane perpendicular to the longitudinal plane of the cylinder center where the bottom of the cylinder head is located is defined as the bottom surface of the cylinder head. The angle between the projection of the central axis of the first valve guide on the bottom surface of the cylinder head and the projection of the tangent of the first arc segment on the bottom surface of the cylinder head is defined as b2, and satisfies 0.3b1≤b2≤0.6b1. The tangent of the first arc segment is the tangent passing through the end point of the first arc segment near the intake end. The radius of the first arc segment is r1, and it satisfies 0.4D≤r1≤0.7D.
2. The integrated exhaust manifold according to claim 1, characterized in that, Define the angle between the projection of the center axis of the first valve guide onto the bottom surface of the cylinder head and the projection of the first straight line segment onto the bottom surface of the cylinder head as b3, and satisfy 3b2≤b3≤3b1.
3. The integrated exhaust manifold according to claim 2, characterized in that, The radius of the second arc segment is r2, and it satisfies r1≤r2≤2r1.
4. The integrated exhaust manifold according to claim 3, characterized in that, Extending from the intake end to the outlet end, the third central streamline sequentially includes a second straight line segment and a fifth arc segment. The fifth arc segment extends to the outlet end. The angle between the projection of the cylinder center longitudinal plane onto the bottom surface of the cylinder head and the projection of the second straight line segment onto the bottom surface of the cylinder head is defined as a11, and satisfies 0.3b2≤a11≤0.6b2. The radius of the fifth arc segment is r5, and r1≤r5≤r2.
5. The integrated exhaust manifold according to claim 4, characterized in that, Extending from the intake end to the outlet end, the second central streamline sequentially includes a third arc segment and a fourth arc segment; the valve guide connected to the second manifold is a second valve guide, and the angle between the projection of the central axis of the second valve guide on the bottom surface of the cylinder head and the projection of the tangent of the third arc segment on the bottom surface of the cylinder head is defined as b4, and satisfies 0.5b2≤b4≤b2, and the tangent of the third arc segment is the tangent passing through the endpoint of the third arc segment near the intake end; The radius of the third arc segment is r3, and r1≤r3≤r2; the radius of the fourth arc segment is r4, and r1≤r4≤r3.
6. The integrated exhaust manifold according to claim 5, characterized in that, The plane perpendicular to the end face of the exhaust end, where the center of the exhaust end is located, is defined as the exhaust end center plane. The angle between the projection of the exhaust end center plane onto the bottom surface of the cylinder head and the projection of the extension line of the fifth arc segment near the end of the exhaust end onto the bottom surface of the cylinder head is defined as a12, and b2≤a12≤b1 is satisfied.
7. The integrated exhaust manifold according to claim 6, characterized in that, The plurality of exhaust manifolds also include a second exhaust manifold and a third exhaust manifold arranged in sequence, wherein the third exhaust manifold is located near the exhaust end.
8. An engine, characterized in that, Including the integrated exhaust manifold as described in any one of claims 1-7.