Airflow channel noise reduction mechanism and compressor volute with noise reduction function

Abstract

The application discloses a kind of airflow passage noise reduction mechanism and compressor volute with silencing function, it is related to the technical field of noise reduction mechanism, including vibrating diaphragm and connecting rod, connecting rod is connected with several vibrating diaphragms, vibrating diaphragm is located in the air outlet of airflow passage, and connecting rod is fixed on airflow passage.The application is through airflow passage noise reduction mechanism, utilizes the time difference of gas-solid sound transmission, realizes airflow multi-band sound attenuation, can effectively improve the noise generated in the internal airflow passage of existing supercharged engine compressor, to reduce the aerodynamic noise at the air outlet of compressor airflow passage.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of noise reduction mechanism, and particularly relates to an air flow passage noise reduction mechanism and a turbocharger volute with a noise reduction function. BACKGROUND

[0002] In recent years, with the progress of design technology, turbochargers are continuously developing towards large flow and high pressure ratio, and the noise problem of turbochargers is increasingly prominent. However, the characteristics of high compression ratio of turbochargers make the energy of compressed air discharged by the compressor greatly increase, which produces exhaust noise with high frequency and wide band characteristics at the outlet of the compressor, and the exhaust noise is radiated outward through the exhaust pipe to become one of the main noise sources of the turbocharger. Excessive noise not only is a potential hidden danger for the normal operation of the equipment, but also is not conducive to the normal work and life of the staff.

[0003] A large number of studies have confirmed that the frequency of the aerodynamic noise of the compressor is high, and it is one of the main noise sources of the turbocharger. Reducing the aerodynamic noise of the compressor can effectively reduce the overall noise of the turbocharger. One of the main methods to reduce noise is to control noise on the propagation path of noise. At present, the method of adding a muffler is often used to reduce noise. However, the traditional Helmholtz resonator and expansion chamber muffler cannot effectively suppress such wideband noise, and there are few measures to reduce noise by changing the structure of the air flow passage of the compressor.

[0004] In summary, the noise generated by the existing turbocharger is too large, which increases the potential hidden danger for the normal operation of the equipment, and is not conducive to the normal work and life of the staff. SUMMARY

[0005] The purpose of the present application is to provide an air flow passage noise reduction mechanism and a turbocharger volute with a noise reduction function to solve the problems existing in the prior art and significantly reduce the aerodynamic noise at the air outlet of the air flow passage.

[0006] To achieve the above purpose, the present application provides the following solutions:

[0007] The present application provides an air flow passage noise reduction mechanism, which comprises a vibrating diaphragm and a connecting rod, a plurality of vibrating diaphragms are connected to the connecting rod, the vibrating diaphragms are located in the air outlet of the air flow passage, and the connecting rod is fixed to the air flow passage.

[0008] Preferably, a plurality of supporting rods are arranged on the connecting rod, and one vibrating diaphragm is connected to the end of each supporting rod, and the connecting rod is connected to the air flow passage through a supporting rod.

[0009] Preferably, the supporting rods penetrate the outer wall of the air flow passage, and the supporting rod is connected to the outer surface of the air flow passage.

[0010] Preferably, the vibrating diaphragm is a light diaphragm, and the material of the light diaphragm comprises polyvinyl chloride, polyvinylidene fluoride and polyvinyl fluoride.

[0011] Preferably, the vibrating diaphragm is arranged to satisfy the half-wavelength noise elimination principle, so that the different sound transmission paths satisfy

[0012] Preferably, the connecting rod is a light connecting rod, and the material of the light connecting rod comprises aluminum alloy, glass fiber reinforced plastic and carbon fiber.

[0013] Preferably, the vibrating diaphragm is oval, circular, rhombic or regular polygonal, and the area is not greater than 1 / 20 of the cross-sectional area of the airflow channel.

[0014] Preferably, the airflow channel noise reduction mechanism is arranged in several groups along the axial direction and the circumferential direction of the air outlet.

[0015] The present application also relates to a compressor volute with a noise elimination function, comprising the above-mentioned airflow channel noise reduction mechanism and the compressor volute of the turbocharger, and the air outlet of the compressor volute is uniformly arranged with several groups of the airflow channel noise reduction mechanism.

[0016] The present application has the following technical effects compared with the prior art:

[0017] The present application uses the airflow channel noise reduction mechanism to utilize the time difference of gas-solid sound transmission, realizes airflow multi-frequency band noise elimination, and can effectively improve the noise generated in the compressor airflow channel of the existing supercharged engine, thereby reducing the aerodynamic noise at the air outlet of the compressor airflow channel. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0019] Figure 1 It is a structural schematic view of the airflow channel noise reduction mechanism in the embodiments of the present application.

[0020] Figure 2 It is a structural schematic view of the compressor volute with a noise elimination function in the embodiments of the present application.

[0021] Figure 3 It is a principle schematic view of the airflow channel noise reduction in the embodiments of the present application.

[0022] Figure 4This is a schematic diagram of the end face structure of the airflow channel in an embodiment of the present invention;

[0023] Figure 5 This is a schematic diagram of the noise propagation path in an embodiment of the present invention;

[0024] In the diagram: 1-Inlet, 2-Compressor volute, 3-Outlet, 4-Connecting rod, 5-Upstream diaphragm, 6-Downstream diaphragm, 7-Support rod, 8-Support rod. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] The purpose of this invention is to provide an airflow channel noise reduction mechanism and a compressor volute with a noise reduction function to solve the problems existing in the prior art and significantly reduce the aerodynamic noise at the air outlet of the airflow channel.

[0027] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] Example 1

[0029] like Figures 1 to 5 As shown, this embodiment provides an airflow channel noise reduction mechanism, including a vibrating diaphragm and a connecting rod 4. Several vibrating diaphragms are connected to the connecting rod 4. The vibrating diaphragms are located inside the air outlet 3 of the airflow channel, and the connecting rod 4 is fixed to the airflow channel.

[0030] As an optional solution, in this embodiment, the connecting rod 4 is provided with several support rods 8, and a vibrating diaphragm is connected to the end of each support rod 8. The connecting rod 4 is connected to the airflow channel through a support rod 7. The design of the support rods 8 provides multiple sound transmission channels from the upstream diaphragm 5 to different downstream diaphragms 6, thereby allowing many trains of sound waves with different transmission distances to be transmitted from the downstream diaphragm 6. The path difference between each train of sound waves is continuous within a certain range. This allows the interference between the sound waves transmitted from the downstream lightweight diaphragm 6 of this invention to have a noise reduction effect on noise within a relatively wide frequency band, such as... Figure 3 As shown.

[0031] As an option, the support rod 8 in the embodiment penetrates the outer wall of the airflow channel, wherein the diameter of the support rod 8 is smaller than the diameter of the hole penetrating the outer wall, and the gap fit prevents additional noise caused by vibration between the support rod and the pipe wall, and the support rod 7 is connected to the outer surface of the airflow channel.

[0032] As an option, the diaphragm in the embodiment is a lightweight diaphragm, and the material of the lightweight diaphragm includes but is not limited to polyvinyl chloride (PVC), polyvinylidene fluoride (PVDF), and polyvinyl fluoride (PVF).

[0033] As an option, the arrangement position of the diaphragm in the embodiment satisfies the half-wavelength noise elimination principle, and ensures that different sound transmission paths satisfy In order to appear the upstream diaphragm 5 and the downstream diaphragm 6, the diaphragm first contacting the noise is the upstream diaphragm 5, and the rest is the downstream diaphragm 6, so that the sound wave can be conducted by the airflow and the connecting rod 4 respectively, and then the time difference of the gas-solid conduction appears.

[0034] As an option, the connecting rod 4 in the embodiment is a lightweight connecting rod, and the material of the lightweight connecting rod includes but is not limited to aluminum alloy, glass steel, carbon fiber, etc.

[0035] As an option, the diaphragm in the embodiment is elliptical, circular, rhombic, and regular polygonal, and the area is not greater than 1 / 20 of the cross-sectional area of the airflow channel, and the distance d between the diaphragm and the inner wall of the volute is not greater than 1 / 20 of the cross-sectional diameter D of the volute flow passage, so as to reduce the influence on the internal flow of the volute as much as possible, as shown in the following formula Figure 4 d<1 / 20D.

[0036] As an option, the airflow channel noise reduction mechanism in the embodiment is evenly arranged in the axial direction and the circumferential direction of the air outlet 3.

[0037] Embodiment two

[0038] As shown in the following formula Figure 2 , the embodiment provides a compressor volute with a noise elimination function, which includes the airflow channel noise reduction mechanism of the above-mentioned embodiment one and the compressor volute 2 of the turbocharger, and the air outlet 3 of the compressor volute 2 is evenly arranged in the axial direction and the circumferential direction of the air outlet 3. Several groups of airflow channel noise reduction mechanisms are arranged, and the compressor volute 2 is provided with an annular air inlet 1.

[0039] The working principle of the airflow passage noise reduction mechanism in the embodiment is as follows: the noise generated by the airflow passage first causes the upstream diaphragm 5 to vibrate, on one hand, the sound wave is conducted to the downstream diaphragm 6 at different positions through the airflow; on the other hand, the sound wave drives the downstream diaphragm 6 at different positions to vibrate through the connecting rod 4, and then the noise is transmitted by each downstream diaphragm 6, and due to the structure of the structural support rod 8 of the connecting rod 4, the noise will generate several interfering sound waves when passing through each support rod 8 and the downstream diaphragm 6, and the wavelength difference between different sound waves will make the interference of the sound waves reduce the noise. Here, the wavelength of the noise sound wave is λ, so as long as the wavelength difference between the noise wavelength λ1 of the downstream diaphragm 6 of the main pipeline of the compressor volute 2 and the sound wave wavelength λ generated by the noise of the vibration of the upstream and downstream diaphragms of the structural transmission noise reduction device is one-half, considering the interference between the two sound waves, the wave peaks of the two sound waves coincide with the wave troughs of the other, which reduces the amplitude and thus reduces the noise, for details, see Figure 3 Because this process forms a rapid sound transmission channel, when the sound wave is incident from the main pipeline to the upstream diaphragm 5, the thin film is excited to do periodic vibration, the light and rigid bifurcated rod between the two thin films plays a role in transmitting the sound wave, and the excited sound wave of the upstream diaphragm 5 is immediately transmitted to the downstream diaphragm 6, so that the same vibration form occurs, at this time, the time delay of the sound wave from the upstream diaphragm 5 to the downstream diaphragm 6 is almost zero (solid propagation), which causes a certain phase difference between the sound propagation of the cavity and the main pipeline (different gas-solid propagation speeds), and thus achieves the purpose of sound wave interference cancellation, thereby achieving the effect of reducing noise.

[0040] The specific calculation is as follows: assuming that the noise sound wave is λ, the noise transmission path from the main pipeline of the volute is l1, and the noise transmission path through the structural bypass transmission device is l2, as shown in the following formula Figure 5 By setting the distance between the upstream and downstream diaphragms of the structural bypass transmission device to make the difference between the different transmission paths be:

[0041]

[0042] The principle and implementation mode of the present application are described by using specific examples in the present application, and the above embodiment is only used to help understand the method and core idea of the present application; meanwhile, for those skilled in the art, according to the idea of the present application, the specific implementation mode and application range will be changed. In view of the above, the content of the specification should not be understood as a limitation of the present application.

Claims

1. An air flow passage noise reduction mechanism, characterized by: The vibration diaphragm and the connecting rod arranged along the axis of the airflow channel, the two ends of the connecting rod are respectively provided with a vibration diaphragm, the connecting rod is provided with a plurality of support rods, the end of each support rod away from the connecting rod is connected with a vibration diaphragm, the vibration diaphragm is located in the air outlet of the airflow channel, and the connecting rod is connected to the airflow channel through a support rod; The arrangement position of the vibrating diaphragm satisfies the half-wavelength sound elimination principle, ensuring that different sound transmission paths satisfy , is the sound wave of the assumed noise, is the path of noise transmission from the airflow channel, is the path of noise transmission through the structural bypass conduction device, and the connecting rod and the branch rod form the structural bypass conduction device.

2. The air flow passage noise reduction mechanism according to claim 1, characterized by: The support rod penetrates the outer wall of the airflow channel, and the support rod is connected to the outer surface of the airflow channel.

3. The air flow passage noise reduction mechanism according to claim 1, characterized by: The vibration diaphragm is a light diaphragm.

4. The air flow passage noise reduction mechanism according to claim 1, characterized by: The connecting rod is a light connecting rod.

5. The air flow passage noise reduction mechanism according to claim 1, characterized by: The vibration diaphragm is elliptical, circular, rhombic or regular polygonal, and the area is not greater than 1 / 20 of the cross-sectional area of the airflow channel.

6. The air flow passage noise reduction mechanism according to claim 1, characterized by: The airflow channel noise reduction mechanism is uniformly arranged along the axis direction and the circumference of the air outlet.

7. A compressor volute having a muffling function, characterized by: The turbocharger compressor volute comprising the airflow channel noise reduction mechanism and the turbocharger of any one of claims 1-6, and a plurality of sets of the airflow channel noise reduction mechanism are uniformly arranged on the air outlet of the compressor volute.

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