Hub and vehicle
By setting a noise reduction unit on the mounting surface of the wheel hub body and utilizing a combination of resonant cavity and reflective cavity, the wheel hub noise problem is solved, achieving a highly efficient noise reduction effect and improving driving comfort.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- BYD CO LTD
- Filing Date
- 2025-06-12
- Publication Date
- 2026-05-05
AI Technical Summary
The noise generated by wheel hubs during vehicle operation has gradually become a major concern, as existing technologies struggle to effectively reduce noise and affect driving comfort.
A noise reduction unit is installed on the mounting surface of the wheel hub body. Noise reduction is achieved by incident sound waves through the incident channel. The combination structure of resonant cavity, reflection cavity and separator is used to achieve noise reduction in multiple frequency points or broadband range and enhance the interaction between noise sound waves and noise reduction unit.
It improves noise reduction efficiency, especially the sound absorption effect in the frequency range of tire noise, enhances noise energy attenuation and frequency response, and adapts to complex noise environments.
Smart Images
Figure CN224197532U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of noise reduction technology, and in particular to a wheel hub and a vehicle. Background Technology
[0002] In modern vehicles, the wheel hub, as a key component connecting the vehicle body and tires, plays a vital role in transmitting power and bearing loads during operation. However, with increasing vehicle speeds and higher demands for driving comfort, the noise generated by the wheel hub during operation has gradually become a major concern. Utility Model Content
[0003] This application provides a wheel hub with noise reduction function and high noise reduction efficiency.
[0004] To achieve the above objectives, according to a first aspect of this application, a wheel hub is provided, comprising:
[0005] A wheel hub body, wherein a mounting surface is provided on the periphery of the wheel hub body;
[0006] A noise reduction unit is disposed on the mounting surface. An incident channel is provided on the side of the noise reduction unit away from the mounting surface, and the noise reduction unit reduces noise by incident sound waves through the incident channel.
[0007] Optionally, the incident channel is arranged radially along the hub body.
[0008] Optionally, the noise reduction unit is attached to the mounting surface.
[0009] Optionally, the number of noise reduction units is multiple, and the multiple noise reduction units form at least one noise reduction configuration.
[0010] Optionally, there are multiple noise reduction configurations, which are arranged continuously or intermittently along the circumference of the wheel hub body.
[0011] Optionally, at least one or more noise reduction units within each of the noise reduction configurations are arranged in one or more columns along the axial direction of the wheel hub body.
[0012] Optionally, a resonant cavity is provided in the noise reduction unit, the incident channel is connected to the resonant cavity, and at least one or more noise reduction units are provided in each noise reduction configuration, and the multiple noise reduction units in the same noise reduction configuration are coupled to reduce noise at multiple frequency points or in a wide range.
[0013] Optionally, the absorption frequencies of the multiple noise reduction units located within the same noise reduction configuration are all different.
[0014] Optionally, the incident channels of the plurality of noise reduction units located within the same noise reduction configuration differ from each other in at least one of their diameter and cross-sectional area; or / and,
[0015] The resonant cavities of the multiple noise reduction units located within the same noise reduction configuration are different from each other in at least one of the following: volume, length, or cross-sectional area. In this application, " / " specifically means "or".
[0016] Optionally, at least one or each of the noise reduction units has two or more resonant cavities, and a connecting channel is provided between two adjacent resonant cavities in the same noise reduction unit to connect them.
[0017] Optionally, two or more of the resonant cavities located within the same noise reduction unit are arranged radially along the hub body.
[0018] Optionally, the noise reduction unit is provided with a reflective cavity to increase the sound wave propagation distance, and the incident channel is connected to the reflective cavity.
[0019] Optionally, the noise reduction unit includes a first sidewall, a second sidewall, and a plurality of separators. The first sidewall and the second sidewall are disposed opposite to each other. The reflection cavity is located between the first sidewall and the second sidewall. The plurality of separators are respectively disposed on the first sidewall and the second sidewall, and the separators located on the first sidewall and the separators located on the second sidewall are arranged alternately in the reflection cavity.
[0020] Optionally, the separators located within the same reflective cavity have the same length.
[0021] Optionally, at least one or more noise reduction units are included in each of the noise reduction configurations. The multiple noise reduction units of the same noise reduction configuration are arranged circumferentially along the hub body, and the phase delay of the sound waves of the multiple noise reduction units along the circumferential direction in the same noise reduction configuration gradually increases.
[0022] Optionally, the length of the separators in multiple noise reduction units along the circumferential direction within the same noise reduction configuration increases sequentially.
[0023] According to a second aspect of this application, a vehicle is also provided, including the aforementioned wheel hub.
[0024] In the wheel hub of this application, the noise reduction unit is disposed on the mounting surface of the wheel hub body, and the incident channel of the noise reduction unit is located on the side of the noise reduction unit away from the mounting surface, directly exposed on the outer periphery of the wheel hub. When a tire is mounted on the wheel hub, the incident channel faces directly towards the tire for noise reduction. During the aforementioned noise reduction process, the noise waves generated by the tire can be directly incident into the noise reduction unit through the incident channel for noise reduction, which is more conducive to the interaction between the noise waves and the noise reduction unit, resulting in higher noise reduction efficiency.
[0025] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description
[0026] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0027] To gain a more complete understanding of this application and its beneficial effects, the following description will be provided in conjunction with the accompanying drawings, wherein the same reference numerals in the following description denote the same parts.
[0028] Figure 1 This is a schematic diagram of the structure of the wheel hub body provided in an exemplary embodiment of this disclosure.
[0029] Figure 2 This is a cross-sectional view of a noise reduction configuration combining a hub body and a resonant unit with a single-layer resonant cavity, as provided in an exemplary embodiment of this disclosure.
[0030] Figure 3 yes Figure 2 An enlarged schematic diagram of part A in the middle.
[0031] Figure 4 This is a cross-sectional view of a noise reduction configuration combining a hub body and a resonant unit with a double-layer resonant cavity, as provided in an exemplary embodiment of this disclosure.
[0032] Figure 5 yes Figure 4 Enlarged schematic diagram of part B.
[0033] Figure 6 This is a cross-sectional view of a noise reduction configuration combining a hub body and a resonant unit with a reflective cavity, as provided in an exemplary embodiment of this disclosure.
[0034] Figure 7 yes Figure 6 Cross-sectional view of the noise reduction configuration.
[0035] Figure 8yes Figure 2 Example table of parameters for noise reduction configuration.
[0036] Figure 9 yes Figure 2 The diagram shown is a simulation illustration of the wheel hub in COMSOL.
[0037] Figure 10 yes Figure 2 The diagram shows the sound absorption effect of the wheel hub.
[0038] Figure 11 yes Figure 4 Example table of parameters for noise reduction configuration.
[0039] Figure 12 yes Figure 4 The diagram shown is a simulation illustration of the wheel hub in COMSOL.
[0040] Figure 13 yes Figure 4 The diagram shows the sound absorption effect of the wheel hub.
[0041] Figure 14 yes Figure 6 Example table of parameters for noise reduction configuration.
[0042] Figure 15 yes Figure 6 The diagram shown is a simulation illustration of the wheel hub in COMSOL.
[0043] Figure 16 yes Figure 6 The diagram shows the sound absorption effect of the wheel hub.
[0044] Explanation of reference numerals in the attached figures:
[0045] 1. Wheel hub body; 11. Mounting surface;
[0046] 2. Noise reduction unit; 21. Incident channel; 22. Resonance cavity; 23. Connecting channel; 24. Reflection cavity; 25. First sidewall; 26. Second sidewall; 27. Separator. Detailed Implementation
[0047] 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 a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the protection scope of this application.
[0048] The first aspect of this application provides a wheel hub, combined with... Figure 1-3The wheel hub includes a wheel hub body 1 and a noise reduction unit 2. The wheel hub body 1 has a mounting surface 11 on its periphery. The noise reduction unit 2 is located on the mounting surface 11. An incident channel 21 is provided on the side of the noise reduction unit 2 away from the mounting surface 11. The noise reduction unit 2 reduces noise by incident sound waves through the incident channel 21.
[0049] When using this wheel hub, the tire can be first fitted around the circumference of the wheel hub body 1, and then the wheel hub body 1 can be installed on the mobile device to assist in the movement of the mobile device. As the mobile device moves, the incident channel 21 of the noise reduction unit 2 is directly aligned with the inner side of the tire. The noise waves generated by the tire during movement can be directly incident into the noise reduction unit 2 through the incident channel 21 for noise reduction, which is more conducive to the interaction between the noise waves and the noise reduction unit 2, resulting in higher noise reduction efficiency.
[0050] In some embodiments, the incident channel 21 is arranged radially along the hub body 1. When the hub is in use, the incident channel 21 arranged radially along the hub body 1 is more conducive to the incident of tire noise waves into the noise reduction unit 2, which can enhance the interaction between the noise reduction unit 2 and the tire noise waves and improve the noise reduction efficiency.
[0051] In some embodiments, the noise reduction unit 2 is attached to the mounting surface 11, which improves the connection stability between the noise reduction unit 2 and the wheel hub body 1, and can make more reasonable use of the space around the wheel hub body 1, reducing the impact on the original structure of the wheel hub body 1.
[0052] In some embodiments, there are multiple noise reduction units 2, and the multiple noise reduction units 2 form at least one noise reduction configuration. The noise reduction configuration formed by multiple noise reduction units 2 is more conducive to improving the noise reduction efficiency of the wheel hub.
[0053] In some embodiments, multiple noise reduction configurations are arranged continuously along the circumference of the wheel hub body 1, ensuring that incident sound waves at various positions along the circumference of the wheel hub body 1 are effectively absorbed. In other implementations, the noise reduction configurations can also be arranged intermittently along the circumference of the wheel hub body 1, and the specific discontinuity distance can be adjusted according to design and usage requirements.
[0054] In some embodiments, at least one or more noise reduction units 2 are present in each noise reduction configuration, and they are arranged in one or more columns along the axial direction of the hub body 1. The number of columns of noise reduction units 2 arranged along the axial direction of the hub body 1 can be selected according to the noise reduction requirements to adjust the noise reduction effect of the hub body 1 in the axial direction (hub thickness direction).
[0055] Specifically, the noise reduction unit 2 can be made of composite materials such as resin, or metal materials such as steel and aluminum alloy. When it is a composite material, structural adhesive is preferred for fixing to the wheel hub, and welding is preferred for fixing to metal materials.
[0056] In some embodiments, this embodiment is based on the above embodiments, combined with Figure 2-3 The noise reduction unit 2 is equipped with a resonant cavity 22, specifically a Helmholtz resonant cavity. The incident channel 21 is connected to the resonant cavity 22. At least one noise reduction unit 2 or multiple noise reduction units 2 are present in each noise reduction configuration, and multiple noise reduction units 2 within the same noise reduction configuration are coupled to reduce noise at multiple frequency points or over a wide range. The resonant cavities 22 of different noise reduction units 2 do not perform noise reduction independently, but rather achieve multi-frequency point or wide-range noise reduction through acoustic-vibration coupling between multiple noise reduction units 2, thereby achieving a better noise reduction effect.
[0057] In some embodiments, the absorption frequencies of multiple noise reduction units 2 located in the same noise reduction configuration are different, which can cover a wider frequency range to meet the requirements of more efficient noise absorption in the tire noise frequency band and adapt to complex noise characteristics.
[0058] In some embodiments, the incident channels 21 of the plurality of noise reduction units 2 located in the same noise reduction configuration are at least one different from each other in terms of diameter and cross-sectional area; or / and,
[0059] Among the multiple noise reduction units 2 located in the same noise reduction configuration, the resonant cavities 22 are different from each other in at least one of volume, length, and cross-sectional area.
[0060] For noise reduction unit 2, the absorption frequency of the resonant cavity 22 can be adjusted by modifying parameters such as the diameter and cross-sectional area of the incident channel 21, as well as the volume, length, and cross-sectional area of the resonant cavity 22. This ensures that the absorption frequencies of multiple noise reduction units 2 located within the same noise reduction configuration are different. The specific formula for calculating the absorption frequency f of the noise reduction unit 2 is as follows:
[0061]
[0062] Where c is the speed of sound in air, r is the radius of the incident channel 21, V is the volume of the resonant cavity 22, and l is the length of the incident channel 21.
[0063] For example, the number of noise reduction configurations is specifically twelve, which are continuously arranged along the circumferential surface of the wheel hub body 1 to fill the mounting surface 11 of the entire circumference of the wheel hub body 1. One noise reduction configuration has twelve noise reduction units 2, arranged in a two-by-six configuration, that is, arranged in two columns along the axial direction of the wheel hub body 1, each column including six noise reduction units 2 arranged along the circumference of the wheel hub body 1.
[0064] Please combine Figure 8 , where represents the parameters of the twelve noise reduction units 2 in a noise reduction configuration. The parameters include the radius r (in mm) of the incident channel 21 and the volume V (in mm) of the resonant cavity 22. 3The sound absorption frequency f (in Hz) and the length of the incident channel 21 are both 1.5 mm.
[0065] First, the formula for calculating the acoustic impedance of the incident channel 21 is:
[0066]
[0067] The acoustic impedance of the incident channel 21 is divided into two parts. The first term on the right side of the equation is the actual acoustic impedance of the incident channel 21, i.e., the impedance after considering the thermoviscous effect; the last two terms on the right side of the equation are the corrected acoustic impedance caused by the vibration radiation of the incident channel 21. The imaginary unit is represented; ω = 2πf, where f represents the frequency of the sound wave; ρ0 is the mass density of air, c0 is the speed of sound in air, and S... a It is the cross-sectional area of the incident channel 21; It is the complex wavenumber within incident channel 21 after considering the thermoviscosity effect; a γ is the length of the incident channel 21, and γ is the specific heat ratio of air; It is the thermal field function of incident channel 21; It is the viscous field function of the incident channel 21, where J0 and J2 represent the 0th and 2nd order Bessel functions, respectively; d a It is the diameter of the incident channel 21; and These are the viscous wavenumber and thermal wavenumber of incident channel 21, respectively; η is the dynamic viscosity coefficient; C p It is the specific heat at constant pressure; K is the thermal conductivity of air; δ i It is the correction length of the tube end of the incident channel 21.
[0068] The acoustic impedance of resonant cavity 22 is:
[0069]
[0070] Where V is the volume of the cavity portion; It is the equivalent mass density of the air inside the cavity after taking into account the thermoviscosity effect; It is the equivalent speed of sound inside the cavity; It is the equivalent wavenumber within the cavity; and These are the thermal field function and the viscous field function within the cavity, respectively; d c It is the diameter of the equivalent circle of the rectangular cross-section of the cavity; and These are the viscous wavenumber and thermal wavenumber of the cavity, respectively.
[0071] The formula for calculating the acoustic impedance of noise reduction unit 2 is:
[0072]
[0073] Where M = 1, Z a，m Z represents the acoustic impedance of resonant cavity 22. c，m This represents the acoustic impedance of the incident channel 21 corresponding to the resonant cavity 22.
[0074] The total acoustic impedance of the noise reduction configuration satisfies the parallel calculation formula, that is:
[0075]
[0076] Z n It is the acoustic impedance of the nth resonant cavity 22.
[0077] Once the acoustic impedance of the noise reduction configuration is obtained, its normal incident absorption coefficient can be theoretically calculated:
[0078]
[0079] in S0 is the cross-sectional area of the entire noise reduction configuration perpendicular to the normal incident direction of the sound wave.
[0080] The sound absorption effect of the noise reduction configuration was verified through simulation in COMSOL, combined with... Figure 9 The central structure in the figure is the noise reduction configuration that has been arrayed twelve times. The outer ring structure simulates the noise generated by the tire to radiate plane waves of different frequencies towards the center of the circle in order to obtain the sound absorption coefficient of the metamaterial.
[0081] Combination Figure 10 The results show that the sound absorption coefficient is mainly concentrated in the range of 190Hz-250Hz, which is consistent with the tire noise frequency band, and has obvious advantages in noise reduction.
[0082] In some embodiments, this embodiment and Figure 2-3 The main difference between the embodiment shown in the noise reduction unit 2, which has only one resonant cavity, lies in the number of resonant cavities 22. Figure 4-5 Each noise reduction unit 2 contains two resonant cavities 22, and a connecting channel 23 is provided between two adjacent resonant cavities 22 located in the same noise reduction unit 2 to connect the two.
[0083] In some embodiments, two or more resonant cavities 22 located in the same noise reduction unit 2 are arranged radially along the hub body 1.
[0084] For example, the number of noise reduction configurations is specifically twelve, which are continuously arranged along the circumferential surface of the wheel hub body 1 to fill the mounting surface 11 of the entire circumference of the wheel hub body 1. One noise reduction configuration has twelve noise reduction units 2, arranged in a two-by-six configuration, that is, arranged in two columns along the axial direction of the wheel hub body 1, each column including six noise reduction units 2 arranged along the circumference of the wheel hub body 1.
[0085] Please combine Figure 11 Here are the parameters for twelve noise reduction units 2 in a noise reduction configuration. The parameters of noise reduction unit 2 include the radii r1 and r2 (in mm) of the two radially arranged front and rear incident channels 21 (the connecting channel 23 can be considered as one incident channel 21), the volumes V1 and V2 (in mm3) of the two front and rear resonant cavities 22, and their absorption frequency f (in Hz), as shown in the table below. The length of both the front and rear incident channels 21 is 1.5 mm.
[0086] First, the formula for calculating the acoustic impedance of the incident channel 21 is:
[0087]
[0088] The acoustic impedance of the incident channel 21 is divided into two parts. The first term on the right side of the equation is the actual acoustic impedance of the incident channel 21, i.e., the impedance after considering the thermoviscous effect; the last two terms on the right side of the equation are the corrected acoustic impedance caused by the vibration radiation of the incident channel 21. The imaginary unit is represented; ω = 2πf, where f represents the frequency of the sound wave; ρ0 is the mass density of air, c0 is the speed of sound in air, and S... a It is the cross-sectional area of the incident channel 21; It is the complex wavenumber within incident channel 21 after considering the thermoviscosity effect; a γ is the length of the incident channel 21, and γ is the specific heat ratio of air; It is the thermal field function of incident channel 21; It is the viscous field function of the incident channel 21, where J0 and J2 represent the 0th and 2nd order Bessel functions, respectively; d a It is the diameter of the incident channel 21; and These are the viscous wavenumber and thermal wavenumber of incident channel 21, respectively; η is the dynamic viscosity coefficient; C p It is the specific heat at constant pressure; K is the thermal conductivity of air; δ i It is the correction length of the tube end of the incident channel 21.
[0089] The acoustic impedance of resonant cavity 22 is:
[0090]
[0091] Where V is the volume of the cavity portion; It is the equivalent mass density of the air inside the cavity after taking into account the thermoviscosity effect; It is the equivalent speed of sound inside the cavity; It is the equivalent wavenumber within the cavity; and These are the thermal field function and the viscous field function within the cavity, respectively; d c It is the diameter of the equivalent circle of the rectangular cross-section of the cavity; and These are the viscous wavenumber and thermal wavenumber of the cavity, respectively.
[0092] The formula for calculating the acoustic impedance of noise reduction unit 2 is:
[0093]
[0094] Where M represents the number of layers in resonant cavity 22, Z a,m Z represents the acoustic impedance of resonant cavity 22. c,m This represents the acoustic impedance of the incident channel 21 corresponding to the resonant cavity 22 (the connecting channel 23 can be regarded as an incident channel 21).
[0095] The total acoustic impedance of the noise reduction configuration satisfies the parallel calculation formula, that is:
[0096]
[0097] Z n It is the acoustic impedance of the nth resonant cavity 22.
[0098] Once the acoustic impedance of the noise reduction configuration is obtained, its normal incident absorption coefficient can be theoretically calculated:
[0099]
[0100] in S0 is the cross-sectional area of the entire noise reduction configuration perpendicular to the normal incident direction of the sound wave.
[0101] The sound absorption effect of the noise reduction configuration was verified through simulation in COMSOL, combined with... Figure 12 The central structure in the figure is the noise reduction configuration that has been arrayed twelve times. The outer ring structure simulates the noise generated by the tire to radiate plane waves of different frequencies towards the center of the circle in order to obtain the sound absorption coefficient of the metamaterial.
[0102] Finally combined Figure 13 The results show that the sound absorption coefficient is mainly concentrated in the range of 170Hz-220Hz, which is consistent with the tire noise frequency band, and has obvious advantages in noise reduction.
[0103] In some embodiments, this embodiment and Figure 2-3 or Figure 4-5 The main difference between the embodiment where the cavity inside the noise reduction unit 2 is a resonant cavity 22 and the embodiment shown is the type of cavity inside the noise reduction unit 2, combined with Figure 6-7The noise reduction unit 2 is equipped with a reflective cavity 24 to increase the propagation distance of sound waves. The incident channel 21 is connected to the reflective cavity 24. The propagation distance of noise sound waves in the noise reduction unit 2 is increased through the reflective cavity, thereby increasing the propagation time of sound waves in the noise reduction unit 2, enhancing the energy attenuation of sound, adjusting phase characteristics, realizing multiple reflections and absorption, and optimizing frequency response, thereby effectively improving the noise reduction effect.
[0104] In some embodiments, the noise reduction unit 2 includes a first sidewall 25, a second sidewall 26, and a plurality of partitions 27. The first sidewall 25 and the second sidewall 26 are disposed opposite to each other, and the reflection cavity 24 is located between the first sidewall 25 and the second sidewall 26. The plurality of partitions 27 are respectively disposed on the first sidewall 25 and the second sidewall 26, and the partitions 27 located on the first sidewall 25 and the partitions 27 located on the second sidewall 26 are arranged alternately in the reflection cavity 24.
[0105] After the noise sound wave is incident on the surface of the structure, it will propagate within the corresponding structure and then be reflected out. Through the cooperation of the first sidewall 25, the second sidewall 26 and multiple partitions 27, the propagation distance of the noise sound wave in the reflection cavity 24 can be increased more effectively, thereby increasing the propagation time of the sound wave within the structure.
[0106] In some embodiments, the separators 27 located within the same reflecting cavity 24 have the same length. Separators 27 of the same length not only make manufacturing and processing more convenient, but also make it easier to accurately calculate the propagation distance of sound waves within the reflecting cavity 24.
[0107] In some embodiments, at least one or more noise reduction units 2 are present in each noise reduction configuration. These multiple noise reduction units 2 are arranged circumferentially along the hub body 1 within the same noise reduction configuration. Furthermore, the phase delay of the sound waves from the multiple noise reduction units 2 along the circumferential direction within the same noise reduction configuration gradually increases, forming a phase gradient. This allows for effective control of the sound wave propagation path and frequency components. It also helps optimize the sound wave superposition method, improve full-band coverage, reduce resonance and amplification effects, enhance energy attenuation, and adapt to complex noise environments.
[0108] In some embodiments, the length of the separator 27 in the plurality of noise reduction units 2 along the circumferential direction within the same noise reduction configuration increases sequentially, so that the phase delay of the sound waves of the plurality of noise reduction units 2 along the circumferential direction within the same noise reduction configuration gradually increases.
[0109] For example, the number of noise reduction configurations is specifically four, which are continuously arranged along the circumferential surface of the wheel hub body 1 to fill the mounting surface 11 of the entire circumference of the wheel hub body 1. One noise reduction configuration has six noise reduction units 2, arranged in a one-by-six configuration, that is, arranged in a row along the axial direction of the wheel hub body 1, and each row includes six noise reduction units 2 arranged circumferentially along the wheel hub body 1.
[0110] Each noise reduction unit 2 contains several partitions. The partitions in the same noise reduction unit 2 have the same length along the circumference. The partitions in multiple noise reduction units 2 along the circumference in the same noise reduction configuration have an angle (unit: °) relative to the center of the wheel hub body 1.
[0111] For example, in combination Figure 14 Here is the angular data of multiple noise reduction units in noise reduction unit 2:
[0112] According to the generalized Snell's law, when a sound wave is incident on the surface of noise reduction unit 2, the incident angle θ i Reflection angle θ r Acoustic wavelength λ, phase gradient of metamaterial surface The following relationship must be satisfied:
[0113]
[0114] Under the condition of normal incidence of sound waves ((θ) i =0°), in order to form a surface wave, |sinθ is required. r |>1. Based on this condition, we can base the equation on the right side of the above equation. Different phase gradients are designed for different wavelengths, thereby converting incident waves into surface waves and achieving noise reduction.
[0115] Its sound absorption effect was verified through simulation in COMSOL, combined with Figure 15 The central structure in the figure is the noise reduction configuration that has been arrayed four times as described above. The outer ring structure simulates the noise generated by the tire to radiate plane waves of different frequencies towards the center of the circle in order to obtain the sound absorption coefficient of the metamaterial.
[0116] Finally combined Figure 16 The results show that the sound absorption coefficient is mainly concentrated around 530Hz. The reason for this peak sound absorption is that at this frequency, by designing the phase of the reflected wave of the unit structure, the sound wave is made into an evanescent wave that propagates along the surface of the metamaterial after it is incident, which weakens the far-field reflected wave and thus greatly improves the noise reduction effect.
[0117] According to a second aspect of this application, a vehicle is also provided, the vehicle including the wheel hub in any of the above embodiments.
[0118] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.
[0119] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.
[0120] The embodiments, implementation methods, and related technical features of this application can be combined and substituted for each other without conflict.
[0121] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.
Claims
1. A wheel hub, characterized in that, include: A wheel hub body, wherein a mounting surface is provided on the periphery of the wheel hub body; A noise reduction unit is disposed on the mounting surface. An incident channel is provided on the side of the noise reduction unit away from the mounting surface, and the noise reduction unit reduces noise by incident sound waves through the incident channel.
2. A wheel hub according to claim 1, characterized in that, The incident channel is arranged radially along the hub body.
3. A wheel hub according to claim 1, characterized in that, The noise reduction unit is attached to the mounting surface.
4. A wheel hub according to any one of claims 1-3, characterized in that, The number of noise reduction units is multiple, and the multiple noise reduction units form at least one noise reduction configuration.
5. A wheel hub according to claim 4, characterized in that, The noise reduction configuration is multiple, and the multiple noise reduction configurations are arranged continuously or intermittently along the circumference of the wheel hub body.
6. A wheel hub according to claim 4, characterized in that, At least one or more noise reduction units are present in each of the noise reduction configurations, and they are arranged in one or more columns along the axial direction of the wheel hub body.
7. A wheel hub according to claim 4, characterized in that, The noise reduction unit is provided with a resonant cavity, and the incident channel is connected to the resonant cavity. At least one or more noise reduction units are provided in each noise reduction configuration, and the multiple noise reduction units in the same noise reduction configuration are coupled to reduce noise at multiple frequency points or in a wide range.
8. A wheel hub according to claim 7, characterized in that, The absorption frequencies of the multiple noise reduction units located within the same noise reduction configuration are all different.
9. A wheel hub according to claim 8, characterized in that, The incident channels of the plurality of noise reduction units located within the same noise reduction configuration are at least one different from each other in terms of diameter and cross-sectional area; or / and, The resonant cavities of the plurality of noise reduction units located in the same noise reduction configuration are different from each other in at least one of the following: volume, length, and cross-sectional area.
10. A wheel hub according to claim 7, characterized in that, At least one or more of the resonant cavities in each of the noise reduction units are provided, and a connecting channel is provided between two adjacent resonant cavities in the same noise reduction unit to connect the two.
11. A wheel hub according to claim 10, characterized in that, Two or more of the resonant cavities located within the same noise reduction unit are arranged radially along the hub body.
12. A wheel hub according to claim 4, characterized in that, The noise reduction unit is provided with a reflective cavity to increase the sound wave propagation distance, and the incident channel is connected to the reflective cavity.
13. A wheel hub according to claim 12, characterized in that, The noise reduction unit includes a first sidewall, a second sidewall, and a plurality of partitions. The first sidewall and the second sidewall are arranged opposite to each other. The reflection cavity is located between the first sidewall and the second sidewall. The plurality of partitions are respectively arranged on the first sidewall and the second sidewall, and the partitions located on the first sidewall and the partitions located on the second sidewall are arranged alternately in the reflection cavity.
14. A wheel hub according to claim 13, characterized in that, The separators located within the same reflective cavity have the same length.
15. A wheel hub according to claim 13, characterized in that, At least one or more noise reduction units are included in each of the noise reduction configurations. The multiple noise reduction units of the same noise reduction configuration are arranged circumferentially along the hub body, and the phase delay of the sound waves of the multiple noise reduction units along the circumferential direction in the same noise reduction configuration gradually increases.
16. A wheel hub according to claim 15, characterized in that, The lengths of the separators within multiple noise reduction units along the circumferential direction of the same noise reduction configuration increase sequentially.
17. A vehicle, characterized in that, Includes the wheel hub as described in any one of claims 1-16.