Turbocharger and engine

Abstract

The utility model relates to the technical field of superchargers, in particular to a turbocharger and an engine. The turbocharger comprises a first flow channel, a second flow channel and a flow control valve, the first flow channel is provided with a first inlet and a first outlet, the second flow channel is provided with a second inlet and a second outlet, the first inlet is used for being communicated with a first air cylinder of an engine, and the second inlet is used for being communicated with a second air cylinder of the engine and an inlet of an exhaust gas recirculation system. The flow control valve is used for regulating and controlling the flow area of the first outlet and the second outlet. When the engine operates under the medium-high rotating speed working condition and the requirement for the EGR rate is low, the flow control valve controls the flow area of the first outlet to be reduced and the flow area of the second outlet to be increased, the exhaust pressure of the second flow channel can be effectively reduced, then the pressure reduction at an EGR inlet is reduced, the driving pressure difference is reduced, the EGR rate is reduced, the air inflow of an EGR system is reduced, and the EGR efficiency is improved. Therefore, the pumping loss is effectively reduced, and the operation efficiency of the turbocharger is improved.

Description

Technical Field

[0001] The present application relates to the technical field of superchargers, and particularly to a turbocharger and an engine. Background Art

[0002] In order to reduce the emissions of nitrogen oxides (NOx), many engines include an exhaust gas recirculation (EGR) system. The EGR system recirculates part of the exhaust gas back to the combustion chamber. Among them, the ratio between the recirculated exhaust gas flow rate and the total air flow rate entering the combustion chamber is the EGR rate. In order to increase the EGR rate, existing turbochargers usually reduce the fluid flow rate at the vortex end to increase the driving pressure difference. This results in a large pumping loss when the engine operates under medium and high engine speed conditions and the EGR rate requirement is low, thus causing the problem of deteriorated fuel consumption. Summary of the Utility Model

[0003] The present application discloses a turbocharger and an engine to solve the problem that existing turbochargers have large pumping losses, resulting in deteriorated fuel consumption of the engine.

[0004] To achieve the above object, the present application provides the following technical solutions:

[0005] In a first aspect, the present application provides a turbocharger, which includes a first flow channel, a second flow channel, and a flow control valve. The first flow channel is provided with a first inlet and a first outlet. The second flow channel is provided with a second inlet and a second outlet. The first inlet is used to communicate with a first cylinder of the engine. The second inlet is used to communicate with a second cylinder of the engine and the inlet of the exhaust gas recirculation system. The flow control valve is used to regulate the flow areas of the first outlet and the second outlet.

[0006] Further, the cross-sectional area of the first flow channel is larger than that of the second flow channel.

[0007] Further, the turbocharger further includes a turbine housing and a turbine. The turbine housing encloses a receiving cavity. A partition wall is provided in the receiving cavity. The partition wall is used to divide the receiving cavity into a first flow channel and a turbine cavity. A turbine is provided in the turbine cavity. The turbine and the partition wall enclose a part of the second flow channel. The flow control valve is provided at an end of the partition wall away from the first inlet.

[0008] Further, the flow control valve includes a first valve plate. The first valve plate includes a fixed end and a movable end connected to the fixed end. The fixed end is rotatably connected to the partition wall. The movable end can rotate around the fixed end to regulate the flow areas of the first outlet and the second outlet.

[0009] Further, the shape and size of the first outlet of the first flow channel are the same as those of the outer edge of the first valve plate, so that the first valve plate can block the first outlet.

[0010] Furthermore, the partition wall includes a first wall body and a second wall body connected to the first wall body. The first wall body and the turbine housing enclose the front end portion of the second flow passage. The second wall body is an arc-shaped body surrounding the turbine, and the arc-shaped body and the turbine enclose the rear end portion of the second flow passage.

[0011] Furthermore, the turbocharger further includes a turbine housing and a turbine. The turbine housing encloses a receiving cavity, and the turbine is disposed in the receiving cavity. Both the first outlet and the second outlet communicate with the receiving cavity.

[0012] Furthermore, the flow control valve includes a first valve and a second valve. The first valve is disposed in the first flow passage, and the second valve is disposed in the second flow passage.

[0013] In a second aspect, the present application provides an engine, which includes the turbocharger of the first aspect.

[0014] Furthermore, the engine further includes a control unit and an exhaust gas recirculation system. The engine and the exhaust gas recirculation system are both signal-connected to the control unit. The engine includes a first cylinder and a second cylinder. The first cylinder is communicated with the first inlet through a first exhaust pipe, and the second cylinder is communicated with the second inlet through a second exhaust pipe. The second exhaust pipe is communicated with the inlet of the exhaust gas recirculation system.

[0015] For the turbocharger provided by the present application, when the engine operates under medium and high speed conditions and the EGR rate requirement is low, the flow control valve controls the flow area of the first outlet to decrease and the flow area of the second outlet to increase, which can effectively reduce the exhaust pressure of the second flow passage. Since the second flow passage is communicated with the inlet of the EGR system, the pressure drop at the inlet of the EGR is reduced, the driving pressure difference is reduced, the EGR rate is reduced, the intake air volume of the EGR system is reduced, thereby effectively reducing the pumping loss and improving the operating efficiency of the turbocharger. Description of the Drawings

[0016] Figure 1 It is a sectional view of a turbocharger according to an embodiment of the present application;

[0017] Figure 2 It is a sectional view of a turbocharger according to another embodiment of the present application.

[0018] Reference Numerals in the Drawings: 100 - turbine housing; 110 - turbine; 120 - flow control valve; 121 - first valve plate; 122 - first valve; 123 - second valve; 130 - partition wall; 131 - first wall body; 132 - second wall body;

[0019] 10 - fixed end; 20 - movable end;

[0020] 01 - Accommodating cavity; 02 - Turbine cavity; 03 - First flow channel; 04 - Second flow channel; 05 - First inlet; 06 - First outlet; 07 - Second inlet; 08 - Second outlet. Detailed implementation manners

[0021] The following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0022] Figure 1 It is a sectional view of a turbocharger according to an embodiment of the present application. Figure 2 It is a sectional view of a turbocharger according to another embodiment of the present application. Refer to Figure 1 and Figure 2 In an embodiment of the present application, a turbocharger is provided. The turbocharger includes a first flow channel 03, a second flow channel 04, and a flow control valve 120. The first flow channel 03 is provided with a first inlet 05 and a first outlet 06. The second flow channel 04 is provided with a second inlet 07 and a second outlet 08. The first inlet 05 is used to communicate with a first cylinder (not shown in the figure) of the engine. The second inlet 07 is used to communicate with a second cylinder (not shown in the figure) of the engine. The second flow channel 04 is provided with a port for communicating with the inlet of the exhaust gas recirculation system. The flow control valve 120 is used to regulate the flow areas of the first outlet 06 and the second outlet 08.

[0023] Among them, the second cylinder of the engine is communicated with the second inlet 07 through an exhaust pipe, and the exhaust pipe is also communicated with the inlet of the EGR system. That is, the second inlet 07 of the second flow channel 04 is communicated with the inlet of the EGR system, and the pressure value in the second flow channel 04 is equal to the pressure value at the inlet of the EGR system.

[0024] Among them, the cross-sectional area of the first flow channel 03 is larger than that of the second flow channel 04. Therefore, when the lengths are the same, the volume of the first flow channel 03 is larger than that of the second flow channel 04, and the first flow channel 03 can allow more fluid to pass through.

[0025] Refer to Figure 1, the turbocharger further includes a turbine housing 100 and a turbine 110. The turbine housing 100 defines an accommodation cavity 01. A partition wall 130 is provided in the accommodation cavity 01. The partition wall 130 is used to divide the accommodation cavity 01 into a first flow channel 03 and a turbine cavity 02. A turbine 110 is provided in the turbine cavity 02. The turbine 110 and the partition wall 130 enclose a part of a second flow channel 04. The flow control valve 120 is provided at an end of the partition wall 130 away from the first inlet 05. In the turbocharger with the above structure, the accommodation cavity 01 is divided into the first flow channel 03 and the turbine cavity 02 by the partition wall 130, and the turbine 110 and the partition wall 130 enclose the second flow channel 04, realizing the structural design of a dual-flow turbocharger, and the structure is simple and occupies little space.

[0026] In some embodiments of the present application, the flow control valve 120 includes a first valve plate 121. The first valve plate 121 includes a fixed end 10 and a movable end 20 connected to the fixed end 10. The fixed end 10 is rotatably connected to the partition wall 130, and the movable end 20 can rotate around the fixed end 10 to adjust the flow areas of the first outlet 06 and the second outlet 08.

[0027] It can be understood that the shape and size of the first outlet 06 of the first flow channel 03 are the same as the outer edge shape and size of the first valve plate 121, so that the first valve plate 121 can block the first outlet 06. When the first valve plate 121 blocks the first outlet 06, the first flow channel 03 is closed, and the working position of the first valve plate 121 at this time is the first working position A. When the first valve plate 121 rotates to be parallel to the extending direction of the partition wall 130, the flow area of the first outlet 06 is the largest, and the working position of the first valve plate 121 at this time is the second working position B.

[0028] Among them, when the first valve plate 121 switches from the first working position A to the second working position B, the minimum distance between the edge of the first valve plate 121 away from the fixed end 10 and the inner wall of the turbine cavity 02 gradually increases, that is, the flow area of the first outlet 06 gradually increases. Thus, the flow area of the first outlet 06 can be adjusted by the rotation of the first valve plate 121.

[0029] Continue to refer to Figure 1 , when the movable end 20 of the first valve plate 121 rotates along the first direction D from the second working position B, the movable end 20 continues to approach the turbine 110, and the minimum distance between the edge of the movable end 20 away from the fixed end 10 and the turbine 110 gradually decreases, that is, the flow area of the second outlet 08 of the second flow channel 04 becomes smaller, thereby realizing the adjustment of the flow rate of the second flow channel 04.

[0030] Continue to refer to Figure 1, the dividing wall 130 includes a first wall body 131 and a second wall body 132 connected to the first wall body 131. The first wall body 131 and the turbine housing 100 enclose the front end portion of the second flow passage 04, and the second wall body 132 is an arc-shaped body disposed around the turbine 110. The arc-shaped body and the turbine 110 enclose the rear end portion of the second flow passage 04.

[0031] The structure of the turbocharger in the present application has been specifically described above. The working process of the turbocharger under different working conditions will be introduced in detail below:

[0032] 1) When the engine is operating at medium to high speeds and there is sufficient driving pressure difference to control the opening of the EGR valve to make the EGR rate relatively high. Among them, when the engine is operating at medium to high speeds, the exhaust gas volume of the engine is relatively large. Because the cross-sectional area of the first flow passage 03 is larger than that of the second flow passage 04, the pressure in the first flow passage 03 is less than the pressure in the second flow passage 04. At this time, the first valve plate 121 is adjusted to between the first working position A and the second working position B, the flow area of the first outlet 06 is reduced, the pressure in the first flow passage 03 becomes larger, the flow area of the second outlet 08 is relatively large, and the pressure in the second flow passage 04 is reduced. On the one hand, it can keep the difference between the pressure in the first flow passage 03 and the pressure in the second flow passage 04 within a suitable range, which is beneficial to the work of the turbocharger. If the pressure difference between the two is too large, the reliability of the turbocharger will decrease. On the other hand, the pressure in the second flow passage 04 is reduced. Because the second flow passage 04 is connected to the EGR system inlet, the pressure at the inlet of the EGR system is reduced, the driving pressure difference is reduced. At the same time, under the control of the engine control unit, when the EGR rate is relatively high, the control unit adjusts the opening of the EGR valve to increase, thereby reducing the loss along the EGR system and improving the engine thermal efficiency.

[0033] 2) When the engine is operating under the condition of low EGR rate demand, the first valve plate 121 is between the first working position A and the second working position B. The flow area of the second outlet 08 of the second flow passage 04 is relatively large, the exhaust pressure of the second flow passage 04 is small, the pressure at the inlet of the EGR is reduced, the driving pressure difference is reduced, the intake air volume of the EGR system is reduced, the pumping loss is reduced, and the operating efficiency of the turbocharger is effectively improved.

[0034] 3) When the engine is operating at low speed and the EGR driving ability requirement is relatively high, a relatively large driving pressure difference is required. At this time, the first valve plate 121 rotates from the second working position towards the side close to the turbine 110, so as to reduce the flow area of the second outlet 08 of the second flow passage 04, thereby increasing the exhaust pressure of the second flow passage 04, increasing the pressure at the inlet of the EGR, and increasing the driving pressure difference to meet the EGR driving pressure difference requirement.

[0035] 4) When the first cylinder is not working, no fluid passes through the first flow channel 03, and the first valve plate 121 can block the first outlet 06, that is, the flow control valve 120 closes the first flow channel 03. At this time, all the fluid in the second flow channel 04 is used to blow the turbine 110, and the air flow in the second flow channel 04 will not flow back into the first flow channel 03, which can effectively improve the work efficiency of the supercharger.

[0036] In summary, the turbocharger in the present application can adjust the flow control valve according to the working conditions of the engine and the preset range of the EGR rate, so as to regulate the flow rates of the first flow channel 03 and the second flow channel 04, ensure that there is enough gas to blow the turbine 110, and control the opening of the EGR valve within a suitable range, so that the EGR rate reaches the preset range, meet the full working condition requirements of the engine, reduce the pumping loss, and thus optimize the performance of the engine and improve the fuel economy.

[0037] In some embodiments of the present application, referring to Figure 2 , the turbocharger includes a turbine housing 100 and a turbine 110. The turbine housing 100 surrounds and forms an accommodation cavity 01, and a turbine 110 is provided in the accommodation cavity 01. The first outlet 06 and the second outlet 08 are both communicated with the accommodation cavity 01.

[0038] Continuing to refer to Figure 2 , the flow control valve 120 includes a first valve 122 and a second valve 123. The first valve 122 is provided in the first flow channel 03, and the first valve 122 can control the flow rate of the first flow channel 03. The second valve 123 is provided in the second flow channel 04, and the second valve 123 can control the flow rate of the second flow channel 04.

[0039] It can be understood that the turbocharger with such a structure can also regulate the first valve 122 and the second valve 123 according to the different working conditions of the engine and the preset range of the EGR rate, so as to adjust the flow rates of the first flow channel 03 and the second flow channel 04, ensure that there is enough gas to blow the turbine 110, and control the opening of the EGR valve within a suitable range, so that the EGR rate reaches the preset range, thereby optimizing the performance of the engine. For the specific regulation method, please refer to the regulation method of the first valve plate 121 of the flow control valve 120 of the turbocharger in the above embodiments of the present application, and details will not be elaborated here.

[0040] Based on the same concept, the present application provides an engine, which includes the turbocharger in various possible embodiments of the present application. Therefore, the engine in the embodiments of the present application also has the advantages of reduced pumping loss and improved fuel economy.

[0041] Optionally, the engine further includes a control unit and an exhaust gas recirculation system. The engine and the exhaust gas recirculation system are both connected to the control unit by signals. The engine includes a first cylinder and a second cylinder. The first cylinder is connected to a first inlet through a first exhaust pipe, and the second cylinder is connected to a second inlet through a second exhaust pipe. The second exhaust pipe is connected to the inlet of the exhaust gas recirculation system.

[0042] Obviously, those skilled in the art can make various changes and modifications to the embodiments of the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalent technologies, the present application also intends to include these modifications and variations.

Claims

1. A turbocharger, characterized in that: It includes a first flow channel, a second flow channel and a flow control valve, the first flow channel is provided with a first inlet and a first outlet, the second flow channel is provided with a second inlet and a second outlet, the first inlet is used to communicate with a first cylinder of the engine, the second inlet is used to communicate with a second cylinder of the engine and an inlet of an exhaust gas recirculation system, and the flow control valve is used to regulate the flow area of ​​the first outlet and the second outlet.

2. The turbocharger according to claim 1, characterized in that: A cross-sectional area of ​​the first flow channel is greater than a cross-sectional area of ​​the second flow channel.

3. The turbocharger according to claim 1, characterized in that: The turbocharger also includes a turbine housing and a turbine. The turbine housing is arranged to form an accommodating chamber. A partition wall is arranged in the accommodating chamber. The partition wall is used to separate the accommodating chamber into the first flow channel and a turbine chamber. The turbine is arranged in the turbine chamber. The turbine and the partition wall are arranged to form part of the second flow channel. The flow control valve is arranged at an end of the partition wall away from the first inlet.

4. The turbocharger according to claim 3, characterized in that: The flow control valve includes a first valve plate, which includes a fixed end and a movable end connected to the fixed end, the fixed end is rotatably connected to the partition wall, and the movable end can rotate around the fixed end to adjust the flow area of ​​the first outlet and the second outlet.

5. The turbocharger according to claim 4, characterized in that: The shape and size of the first outlet of the first flow channel are the same as the shape and size of the outer edge of the first valve plate, so that the first valve plate can block the first outlet.

6. The turbocharger according to any one of claims 3 to 5, characterized in that: The partition wall includes a first wall body and a second wall body connected to the first wall body, the first wall body and the turbine housing are arranged to form the front end portion of the second flow channel, the second wall body is an arc-shaped body arranged around the turbine, and the arc-shaped body and the turbine are arranged to form the rear end portion of the second flow channel.

7. The turbocharger according to claim 1 or 2, characterized in that: The turbocharger further includes a turbine housing and a turbine. The turbine housing is surrounded by a housing chamber, the turbine is arranged in the housing chamber, and the first outlet and the second outlet are both in communication with the housing chamber.

8. The turbocharger according to claim 7, characterized in that: The flow control valve includes a first valve and a second valve, wherein the first valve is disposed in the first flow channel, and the second valve is disposed in the second flow channel.

9. An engine, characterized in that: Comprising a turbocharger as claimed in any one of claims 1 to 8.

10. The engine according to claim 9, characterized in that The engine also includes a control unit and an exhaust gas recirculation system, the engine and the exhaust gas recirculation system are both connected to the control unit by signal, the engine includes a first cylinder and a second cylinder, the first cylinder is connected to the first inlet through a first exhaust pipe, the second cylinder is connected to the second inlet through a second exhaust pipe, and the second exhaust pipe is connected to the inlet of the exhaust gas recirculation system.

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