Turbine shell for improving BPF noise of turbine

Abstract

The invention relates to a turbine casing for improving turbine BPF noise. The turbine shell comprises a turbine shell body, an air inlet flange, an air outlet flange and an air outlet flange, the flow channel is communicated with the through opening of the air inlet flange, the flow channel comprises a flow guide section and a worm pipe which are connected, and the flow guide section extends towards the direction close to the worm pipe to form a throat tongue; the turbine shell body is further provided with at least one air inlet channel and / or at least one exhaust channel. The working medium can be introduced into the worm pipe by the air inlet channel through pressure difference; and the working medium can be led out of the worm pipe by the exhaust channel through pressure difference. According to the invention, airflow is led out to a high-pressure and high-momentum area at the upstream of the throat tongue, or airflow is led into a low-pressure and low-momentum area at the downstream of the throat tongue, so that pressure fluctuation near the throat tongue of the turbine shell is improved, excitation to turbine blades is inhibited, and BPF noise of the turbine is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of turbocharging, and particularly to a turbine housing for improving the BPF noise of a turbine. Background Art

[0002] In a turbocharger, a turbine housing is used to guide a working medium (compressed air) into a turbine impeller so that the impeller obtains kinetic energy to drive a compressor to operate. Usually, a non-axisymmetric flow passage structure is arranged inside the turbine housing, including a guiding section and a tapered volute, and a closed tongue structure is formed near the outlet to enhance the gas acceleration and guiding ability. However, due to the influence of the non-axisymmetric layout of the turbine housing and the tongue closing effect, the internal flow field thereof exhibits significant non-uniformity.

[0003] Specifically, the working medium enters the guiding section of the flow passage from an intake flange and then enters the volute. The volute is a tapered channel. Due to the influence of the inherent non-axisymmetric structure of the turbine housing and the tongue closing effect, a low-pressure and high-momentum region is generated downstream of the tongue, while a high-pressure and low-momentum region exists upstream of the tongue. Due to the dual action of the two, a large pressure fluctuation is generated within a small circumferential angle range. When the turbine rotates past the tongue, the pressure fluctuation periodically excites the turbine blades, and the turbine blades vibrate to generate turbine BPF (passing frequency) noise. When the airflow excitation frequency is an integer multiple of the natural frequency of the turbine blades, it will cause high-cycle fatigue damage to the turbine blades, reducing the reliability and life of the entire turbine. Summary of the Invention

[0004] Therefore, the present invention provides a turbine housing for improving the BPF noise of a turbine. By leading out the airflow from the high-pressure and high-momentum region upstream of the tongue or introducing the airflow into the low-pressure and low-momentum region downstream of the tongue, the pressure fluctuation near the tongue of the turbine housing is improved, thereby suppressing the excitation of the turbine blades, improving the BPF noise of the turbine. Due to the improvement of the airflow uniformity, the excitation force of the flow passage of the turbine housing is reduced, the high-cycle fatigue risk of the turbine is reduced, and the life of the entire turbine is prolonged.

[0005] To solve the above technical problems, the present invention provides a turbine housing for improving the BPF noise of a turbine, including a turbine housing body and the following components provided on the turbine housing body: An intake flange for introducing a working medium; A flow passage communicating with the through port of the intake flange. The flow passage includes a connected guiding section and a volute, and a tongue extends from the guiding section towards the volute; Wherein, at least one intake channel and / or at least one exhaust channel are further provided on the turbine housing body; The working medium can be introduced into the volute through the intake passage by a pressure difference; the working medium can be led out of the volute through the exhaust passage by a pressure difference.

[0006] In an embodiment of the present invention, the intake passage includes a first intake port and a first exhaust port that are connected and communicate with each other; The first exhaust port of each intake passage is located on the volute where the downstream flow path angle of the throat is 270° - 360°; the pressure of the first intake port of each intake passage is higher than the pressure of the corresponding first exhaust port. The flow path angle is defined as follows: taking the turbine center inside the turbine housing body as the origin, setting the position where the throat is located as 0°, and the angle increases in the circumferential expansion direction of the volute to form a circumferential angle coordinate system of 0° - 360°, and the 360° position coincides with the 0° position.

[0007] In an embodiment of the present invention, the first intake port of each intake passage is located on the side of the opening of the intake flange and is connected to the compressor outlet or the ventilation device.

[0008] In an embodiment of the present invention, the first intake port of each intake passage is located on the guiding section.

[0009] In an embodiment of the present invention, the value range of the intake flow rate ratio α is: 0 < α ≤ 0.2; Wherein, α = (V4 * A 进 ) / (V2 * A0); V2 is the average air flow velocity of the working medium at the position where the flow path angle is 0°; V4 is the average air flow velocity of the working medium at the first intake port position of the intake passage; A 进 is the cross-sectional area at the first intake port of the intake passage; A0 is the flow path cross-sectional area when the flow path angle is 0°; The flow path angle is defined as follows: taking the turbine center inside the turbine housing body as the origin, setting the position where the throat is located as 0°, and the angle increases in the circumferential expansion direction of the volute to form a circumferential angle coordinate system of 0° - 360°, and the 360° position coincides with the 0° position.

[0010] In an embodiment of the present invention, the exhaust passage includes a second intake port and a second exhaust port that are connected and communicate with each other; The second intake port of each exhaust passage is located on the guiding section or the volute where the upstream flow path angle of the throat is 0° - 90°; the pressure of the second intake port of each exhaust passage is higher than the pressure of the corresponding second exhaust port. The flow channel angle is defined as follows: taking the turbine center inside the turbine housing body as the origin, setting the position where the throat tongue is located as 0°, and the angle increasing in the circumferential expansion direction of the scroll tube to form a circumferential angle coordinate system of 0° to 360°, and the 360° position coincides with the 0° position.

[0011] In an embodiment of the present invention, the second exhaust ports of the exhaust channels are located on the diversion section or the scroll tube with an upstream flow channel angle of 0° - 90° of the throat tongue.

[0012] In an embodiment of the present invention, the value range of the exhaust gas flow rate ratio β is: 0 < β ≤ 0.15; where, β = (V5 * A 出 ) / (V2 * A0); V5 is the average gas flow velocity of the working medium at the position of the second intake port of the exhaust channel; A 出 is the cross-sectional area at the second intake port of the exhaust channel; V2 is the average gas flow velocity of the working medium at the position with a flow channel angle of 0°; A0 is the flow channel cross-sectional area when the flow channel angle is 0°; The flow channel angle is defined as follows: taking the turbine center inside the turbine housing body as the origin, setting the position where the throat tongue is located as 0°, and the angle increasing in the circumferential expansion direction of the scroll tube to form a circumferential angle coordinate system of 0° to 360°, and the 360° position coincides with the 0° position.

[0013] In an embodiment of the present invention, an intake channel and the exhaust channels are provided on the turbine housing body, and the second exhaust ports of the exhaust channels are communicated with the intake channel; The second intake ports and the second exhaust ports of the exhaust channels are respectively located on the diversion section or the scroll tube with an upstream flow channel angle of 0° - 90° of the throat tongue; The first intake port of the intake channel is located on one side of the through port of the intake flange; The first exhaust port of the intake channel is located on the scroll tube with a downstream flow channel angle of 270° - 360° of the throat tongue; The pressure of the second exhaust port is higher than the pressure of the first exhaust port; The flow channel angle is defined as follows: taking the turbine center inside the turbine housing body as the origin, setting the position where the throat tongue is located as 0°, and the angle increasing in the circumferential expansion direction of the scroll tube to form a circumferential angle coordinate system of 0° to 360°, and the 360° position coincides with the 0° position.

[0014] In an embodiment of the present invention, only an air inlet passage is provided on the turbine housing body. The first air inlet of the air inlet passage is located on one side of the through hole of the air inlet flange and is connected to the compressor outlet. The first air outlet of the air inlet passage is located on the scroll tube where the downstream flow path angle of the throat is 270°-360°. The flow path angle is defined as follows: taking the turbine center inside the turbine housing body as the origin, setting the position of the throat as 0°, and the angle increasing in the circumferential expansion direction of the scroll tube to form a circumferential angle coordinate system of 0° to 360°, and the 360° position coincides with the 0° position.

[0015] The above technical solution of the present invention has the following advantages compared with the prior art: The turbine housing for improving the BPF noise of the turbine according to the present invention improves the pressure fluctuation near the throat of the turbine housing by introducing air flow into the high-pressure and high-momentum region upstream of the throat or introducing air flow into the low-pressure and low-momentum region downstream of the throat, thereby suppressing the excitation of the turbine blades and improving the BPF noise of the turbine. Due to the improvement of the air flow uniformity, the excitation force of the flow path of the turbine housing is reduced, the risk of high-cycle fatigue of the turbine is reduced, and the service life of the entire turbine is extended. Description of the Drawings

[0016] In order to make the content of the present invention easier to be clearly understood, the present invention will be further described in detail below according to the specific embodiments of the present invention in conjunction with the drawings.

[0017] Figure 1 It is a schematic structural diagram of the turbine housing for improving the BPF noise of the turbine in Embodiment 1 of the present invention.

[0018] Figure 2 It is a schematic structural diagram of the turbine housing for improving the BPF noise of the turbine in Embodiment 2 of the present invention.

[0019] Figure 3 It is a schematic structural diagram of the turbine housing for improving the BPF noise of the turbine in Embodiment 3 of the present invention.

[0020] Figure 4 It is a schematic structural diagram of the turbine housing for improving the BPF noise of the turbine in Embodiment 4 of the present invention.

[0021] Description of the reference numerals in the drawings: 1. Turbine housing body; 1-1. Air inlet flange; 1-2. Flow path; 1-2-1. Guide section; 1-2-2. Scroll tube; 1-3. Throat; 1-4. Air inlet passage; 1-4-1. First air inlet; 1-4-2. First air outlet; 1-5. Exhaust passage; 1-5-1. Second air inlet; 1-5-2. Second air outlet; 2. Working medium; 3. Turbine. Detailed implementation manners

[0022] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, so that those skilled in the art can better understand the present invention and be able to implement it, but the specific embodiments cited are not intended to limit the present invention.

[0023] In the present invention, when directions (up, down, left, right, front and back) are described, it is only for the convenience of describing the technical solution of the present invention, rather than indicating or implying that the technical features referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0024] In the present invention, the meaning of "several" is one or more, the meaning of "multiple" is more than two, and "greater than", "less than", "exceeding", etc. are understood as not including the present number; "above", "below", "within", etc. are understood as including the present number. In the description of the present invention, if "first" and "second" are described, they are only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or implicitly indicating the sequence relationship of the indicated technical features.

[0025] In the present invention, unless otherwise clearly defined, words such as "set", "installed", "connected", etc. should be understood in a broad sense. For example, they can be directly connected, or indirectly connected through an intermediate medium; they can be fixedly connected, or detachably connected, and can also be integrally formed; they can be mechanically connected, electrically connected or capable of communicating with each other; they can be the communication inside two components or the interaction relationship between two components. Those skilled in the art can reasonably determine the specific meaning of the above words in the present invention in combination with the specific content of the technical solution.

[0026] Embodiment 1 Referring to Figure 1 As shown, a turbine housing for improving the BPF noise of a turbine in this embodiment includes a turbine housing body 1 and the following provided on the turbine housing body 1: An intake flange 1-1 for introducing a working medium 2; A flow channel 1-2 communicating with the through-port of the intake flange 1-1. The flow channel 1-2 includes a connected guiding section 1-2-1 and a volute 1-2-2. The guiding section 1-2-1 extends towards the volute 1-2-2 with a throat 1-3; Wherein, at least one intake channel 1-4 and / or at least one exhaust channel 1-5 are further provided on the turbine housing body 1; The working medium 2 can be introduced into the volute 1-2-2 by the intake channel 1-4 through a pressure difference; the working medium 2 can be led out of the volute 1-2-2 by the exhaust channel 1-5 through a pressure difference.

[0027] It should be noted that the working medium 2 enters the diversion section 1-2-1 of the flow channel 1-2 from the intake flange 1-1, and then enters the volute 1-2-2. The volute 1-2-2 is a gradually shrinking channel. The turbine housing body 1 has an inherent non-axisymmetric structure, and the throat 1-3 is a closed structure.

[0028] The intake channel 1-4 and the exhaust channel 1-5 of the turbine housing can exist separately or simultaneously. That is, the turbine housing can have one or more intake channels 1-4 and no exhaust channel 1-5; or, the turbine housing has one or more exhaust channels 1-5 and no intake channel 1-4; or, the turbine housing has one or more intake channels 1-4 and one or more exhaust channels 1-5.

[0029] Taking the case where both the intake channel 1-4 and the exhaust channel 1-5 exist as an example for description.

[0030] Specifically, the intake channel 1-4 includes a first intake port 1-4-1 and a first exhaust port 1-4-2 that are connected and communicate with each other; Downstream of the throat 1-3 is a low-pressure and high-momentum region, which is located between the flow channel angles of 270°-360°. The first exhaust port 1-4-2 of each intake channel 1-4 is located on the volute 1-2-2 with a flow channel angle of 270°-360° downstream of the throat 1-3, and the pressure of the first intake port 1-4-1 of each intake channel 1-4 is higher than the pressure of the corresponding first exhaust port 1-4-2; The flow channel angle is defined as: taking the center of the turbine 3 inside the turbine housing body 1 as the origin, setting the position where the throat 1-3 is located as 0°, and the angle increases in the circumferential expansion direction of the volute 1-2-2 ( Figure 1 clockwise in the figure) to form a circumferential angle coordinate system of 0°~360°, and the 360° position coincides with the 0° position.

[0031] Specifically, the first intake port 1-4-1 of each intake channel 1-4 is located on the port side of the intake flange 1-1 and is connected to the compressor outlet or a ventilation device (such as an intake pump).

[0032] Specifically, the first intake port 1-4-1 of each intake channel 1-4 is located on the diversion section 1-2-1.

[0033] Specifically, the value range of the intake flow rate ratio α is: 0 < α ≤ 0.2; where α = (V4 * A 进 ) / (V2 * A0); V2 is the average air flow velocity of the working medium 2 at the position where the flow channel angle is 0°; V4 is the average airflow velocity of the working medium 2 at the position of the first air inlet 1-4-1 of the intake passage 1-4; A 进 is the cross-sectional area at the first air inlet 1-4-1 of the intake passage 1-4; A0 is the cross-sectional area of the flow passage 1-2 when the flow passage angle is 0°.

[0034] It should be noted that the pressure at the first air inlet 1-4-1 is higher than that at the first exhaust port 1-4-2. Under the action of the pressure difference, the high-pressure working medium 2 enters the volute 1-2-2 through the intake passage 1-4, which increases the pressure downstream of the throat 1-3, reduces the momentum, and decreases the pressure fluctuation at the position of the throat 1-3. The intake flow ratio is 0 < α ≤ 0.2. When the intake flow ratio continues to increase, the improvement rate of the pressure fluctuation near the throat 1-3 becomes significantly slower, which is due to the adverse effects that an excessive intake flow ratio may bring to the efficiency characteristics of the turbine 3.

[0035] Specifically, the exhaust passage 1-5 includes a connected second air inlet 1-5-1 and a second exhaust port 1-5-2; Upstream of the throat 1-3 is a high-pressure and low-momentum region, which is located between the flow passage angles of 0° - 90°. The second air inlet 1-5-1 of each exhaust passage 1-5 is located on the guide section 1-2-1 or the volute 1-2-2 with a flow passage angle of 0° - 90° upstream of the throat 1-3; the pressure at the second air inlet 1-5-1 of each exhaust passage 1-5 is higher than the pressure at the corresponding second exhaust port 1-5-2.

[0036] Specifically, the second exhaust port 1-5-2 of each exhaust passage 1-5 is located on the guide section 1-2-1 or the volute 1-2-2 with a flow passage angle of 0° - 90° upstream of the throat 1-3.

[0037] Specifically, the value range of the exhaust flow ratio β is: 0 < β ≤ 0.15; where β = (V5 * A 出 ) / (V2 * A0); V5 is the airflow velocity of the working medium 2 at the position of the second air inlet 1-5-1 of the exhaust passage 1-5; A 出 is the cross-sectional area at the second air inlet 1-5-1 of the exhaust passage 1-5; V2 is the average airflow velocity of the working medium 2 at the position where the flow passage angle is 0°; A0 is the cross-sectional area of the flow passage 1-2 when the flow passage angle is 0°.

[0038] It should be noted that the pressure of the second intake port 1-5-1 of the exhaust passage 1-5 is higher than that of the second exhaust port 1-5-2. Under the action of the pressure difference, the high-pressure working medium 2 enters the scroll tube 1-2-2 through the exhaust passage 1-5, reducing the pressure upstream of the throat 1-3, increasing the momentum, and reducing the pressure fluctuation at the position of the throat 1-3. The exhaust flow ratio is 0 < β ≤ 0.15. Continuing to increase the exhaust flow ratio, the improvement rate of the pressure fluctuation near the throat 1-3 becomes significantly slower, because an excessive exhaust flow ratio reduces the working medium 2 entering the turbine 3 to do work, reducing the work capacity of the turbine 3.

[0039] Embodiment 2 Refer to Figure 2 As shown, a turbine housing for improving the BPF noise of a turbine in this embodiment is provided with an intake passage 1-4 separately. The first intake port 1-4-1 and the first exhaust port 1-4-2 of the intake passage 1-4 are both located at the position of the flow path angle of 345°. The first intake port 1-4-1 is located in the guiding section 1-2-1 of the flow path 1-2, and the first exhaust port 1-4-2 is located in the scroll tube 1-2-2. Since the pressure of the working medium 2 in the guiding section 1-2-1 is higher than the pressure of the scroll tube 1-2-2, under the action of the pressure difference, the working medium 2 enters the scroll tube 1-2-2 through the intake passage 1-4, increasing the pressure downstream of the throat 1-3. Since part of the working medium 2 is intercepted, the pressure upstream of the throat 1-3 is slightly reduced. Overall, the pressure fluctuations upstream and downstream of the throat 1-3 are reduced.

[0040] Embodiment 3 Refer to Figure 3 As shown, a turbine housing for improving the BPF noise of a turbine in this embodiment, an intake passage 1-4 and the exhaust passage 1-5 are provided on the turbine housing body 1, and the second exhaust port 1-5-2 of the exhaust passage 1-5 is communicated with the intake passage 1-4; The second intake port 1-5-1 of the exhaust passage 1-5 is located at the position of the flow path angle of 10°, and the first exhaust port 1-4-2 of the intake passage 1-4 is located at the position of the flow path angle of 345°.

[0041] The first intake port 1-4-1 of the intake passage 1-4 is located on the side of the through port of the intake flange 1-1; The pressure of the second exhaust port 1-5-2 is higher than the pressure of the first exhaust port 1-4-2; Since the pressure of the working medium 2 at the second intake port 1-5-1 is higher than the pressure of the first exhaust port 1-4-2, under the action of the pressure difference, the working medium 2 enters the position of 345° from the position of the flow path angle of 10°, which causes the pressure downstream of the throat 1-3 to increase, thereby improving the pressure fluctuations upstream and downstream of the throat 1-3.

[0042] Example 4 Refer to Figure 4 As shown, a turbine housing for improving the BPF noise of a turbine in this embodiment Only an air inlet passage 1-4 is provided on the turbine housing body 1, and the first air inlet 1-4-1 of the air inlet passage 1-4 is located on the side of the through port of the air inlet flange 1-1 and is connected to the outlet of the compressor; The first exhaust port 1-4-2 is located at a position where the flow path angle is 330°. The outlet pressure of the compressor after compression is higher than the pressure at the position where the flow path angle is 330°. Under the action of the pressure difference, the fresh compressed air enters the volute 1-2-2 from the outlet of the compressor, which increases the pressure downstream of the nozzle 1-3 and improves the pressure fluctuation upstream and downstream of the nozzle 1-3. Since the temperature of the fresh compressed air is lower than the temperature of the working medium 2 in the volute 1-2-2, the thermal load of the turbine housing can also be reduced and the thermal fatigue life can be improved.

[0043] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the examples, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.

Claims

1. A turbine housing for improving the BPF noise of a turbine, characterized in that, Comprising a turbine housing body (1) and the following provided on the turbine housing body (1): An intake flange (1-1) for introducing a working medium (2); A flow channel (1-2) communicating with the through-port of the intake flange (1-1), the flow channel (1-2) comprising a connected guiding section (1-2-1) and a scroll tube (1-2-2), the guiding section (1-2-1) extending towards the scroll tube (1-2-2) with a throat (1-3); Wherein, at least one intake channel (1-4) and / or at least one exhaust channel (1-5) are further provided on the turbine housing body (1); The working medium (2) can be introduced into the scroll tube (1-2-2) by the intake channel (1-4) through a pressure difference; the working medium (2) can be led out of the scroll tube (1-2-2) by the exhaust channel (1-5) through a pressure difference.

2. A turbine housing for improving the BPF noise of a turbine according to claim 1, characterized in that, The intake channel (1-4) comprises a connected first intake port (1-4-1) and a first exhaust port (1-4-2); The first exhaust port (1-4-2) of each intake channel (1-4) is located on the scroll tube (1-2-2) where the angle of the downstream flow channel (1-2) of the throat (1-3) is 270° - 360°, and the pressure of the first intake port (1-4-1) of each intake channel (1-4) is higher than the pressure of the corresponding first exhaust port (1-4-2); The angle of the flow channel (1-2) is defined as: taking the center of the turbine (3) inside the turbine housing body (1) as the origin, setting the position where the throat (1-3) is located as 0°, and the angle increasing in the circumferential unfolding direction of the scroll tube (1-2-2) to form a circumferential angle coordinate system of 0° to 360°, and the 360° position coincides with the 0° position.

3. A turbine housing for improving the BPF noise of a turbine according to claim 2, characterized in that, The first intake port (1-4-1) of each intake channel (1-4) is located on one side of the through-port of the intake flange (1-1) and is connected to the compressor outlet or the ventilation device.

4. A turbine housing for improving the BPF noise of a turbine according to claim 2, characterized in that, The first intake port (1-4-1) of each intake channel (1-4) is located on the guiding section (1-2-1).

5. A turbine housing for improving the BPF noise of a turbine according to any one of claims 1-4, characterized in that, The value range of the intake flow rate ratio α: 0 < α ≤ 0.2; where α = (V4 * A 进 ) / (V2 * A0); V2 is the average air flow velocity of the working medium (2) at the position where the angle of the flow channel (1-2) is 0°; V4 is the average air flow velocity of the working medium (2) at the position of the first intake port (1-4-1) of the intake channel (1-4); A 进 is the cross-sectional area at the first air inlet (1-4-1) of the air inlet passage (1-4); A0 is the cross-sectional area of the flow channel (1-2) when the angle of the flow channel is 0°; The angle of the flow channel is defined as: taking the center of the turbine (3) inside the turbine housing body (1) as the origin, setting the position where the throat (1-3) is located as 0°, and the angle increasing in the circumferential unfolding direction of the scroll tube (1-2-2) to form a circumferential angle coordinate system of 0° to 360°, and the 360° position coincides with the 0° position.

6. A turbine housing for improving the BPF noise of a turbine according to claim 1 or 5, characterized in that, The exhaust channel (1-5) comprises a connected second intake port (1-5-1) and a second exhaust port (1-5-2); The second air inlets (1-5-1) of the exhaust passages (1-5) are located on the diversion section (1-2-1) or the volute (1-2-2) with an upstream flow channel angle of 0°-90° of the tongue (1-3); the pressure of the second air inlets (1-5-1) of the exhaust passages (1-5) is higher than the pressure of the corresponding second air outlets (1-5-2). The flow channel angle is defined as: taking the center of the turbine (3) inside the turbine housing body (1) as the origin, setting the position where the tongue (1-3) is located as 0°, and the angle increases in the circumferential expansion direction of the volute (1-2-2) to form a circumferential angle coordinate system of 0°-360°, and the 360° position coincides with the 0° position.

7. A turbine housing for improving the BPF noise of a turbine according to claim 6, characterized in that, The second air outlets (1-5-2) of the exhaust passages (1-5) are located on the diversion section (1-2-1) or the volute (1-2-2) with an upstream flow channel angle of 0°-90° of the tongue (1-3).

8. A turbine housing for improving the BPF noise of a turbine according to any one of claims 6-7, characterized in that, The value range of the exhaust gas flow ratio β: 0 < β ≤ 0.15; where β = (V5 * A 出 ) / (V2 * A0); V5 is the average gas flow velocity of the working medium (2) at the position of the second air inlet (1-5-1) of the exhaust passage (1-5); A 出 is the cross-sectional area at the second air inlet (1-5-1) of the exhaust passage (1-5); V2 is the average gas flow velocity of the working medium (2) at the position where the flow channel angle is 0°; A0 is the cross-sectional area of the flow channel (1-2) when the flow channel angle is 0°; The flow channel angle is defined as: taking the center of the turbine (3) inside the turbine housing body (1) as the origin, setting the position where the tongue (1-3) is located as 0°, and the angle increases in the circumferential expansion direction of the volute (1-2-2) to form a circumferential angle coordinate system of 0°-360°, and the 360° position coincides with the 0° position.

9. A turbine housing for improving the BPF noise of a turbine according to claim 1, characterized in that, An air inlet passage (1-4) and the exhaust passages (1-5) are provided on the turbine housing body (1), and the second air outlet (1-5-2) of the exhaust passage (1-5) is communicated with the air inlet passage (1-4); The second air inlets (1-5-1) and the second air outlets (1-5-2) of the exhaust passages (1-5) are respectively located on the diversion section (1-2-1) or the volute (1-2-2) with an upstream flow channel angle of 0°-90° of the tongue (1-3); The first air inlet (1-4-1) of the air inlet passage (1-4) is located on the side of the through port of the air inlet flange (1-1); The first air outlet (1-4-2) of the air inlet passage (1-4) is located on the volute (1-2-2) with a downstream flow channel angle of 270°-360° of the tongue (1-3); The pressure of the second air outlet (1-5-2) is higher than the pressure of the first air outlet (1-4-2); The flow channel angle is defined as: taking the center of the turbine (3) inside the turbine housing body (1) as the origin, setting the position where the tongue (1-3) is located as 0°, and the angle increases in the circumferential expansion direction of the volute (1-2-2) to form a circumferential angle coordinate system of 0°-360°, and the 360° position coincides with the 0° position.

10. A turbine housing for improving the BPF noise of a turbine according to claim 1, wherein, Only an intake passage (1-4) is provided on the turbine housing body (1). The first intake port (1-4-1) of the intake passage (1-4) is located on the side of the through-port of the intake flange (1-1) and is connected to the compressor outlet. The first exhaust port (1-4-2) of the intake passage (1-4) is located on the volute tube (1-2-2) with a downstream flow path angle of 270° - 360° of the throat (1-3). The flow path angle is defined as follows: Taking the center of the turbine (3) inside the turbine housing body (1) as the origin, the position where the throat (1-3) is located is set as 0°. The angle increases in the circumferential expansion direction of the volute tube (1-2-2) to form a circumferential angle coordinate system of 0° - 360°. The 360° position coincides with the 0° position.

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