A method for evaluating noise reduction performance of a wheel hub resonant cavity, an electronic device, and a medium
By treating the acoustic waves inside the tire cavity as plane waves and calculating the transmission loss curve, the lack of evaluation of the noise reduction performance of the resonant cavity is solved, enabling low-cost and accurate prediction of noise reduction effect, and improving product development efficiency and quality controllability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- KUNSHAN LIUFENG MACHINERY IND CO LTD
- Filing Date
- 2026-03-19
- Publication Date
- 2026-05-29
AI Technical Summary
The lack of a systematic method for evaluating the noise reduction performance of resonant cavities in existing technologies leads to the direct delivery of prototypes to vehicle road tests. This can easily result in a cycle of design, prototyping, and road testing due to substandard performance, resulting in long R&D cycles, high costs, and reduced product development efficiency and design optimization flexibility.
The propagation of sound waves within the tire cavity is equivalent to a plane wave. By calculating the geometric parameters of the resonant cavity, the acoustic impedance and total acoustic impedance are obtained. Then, the transmission loss curve is calculated, and the noise reduction performance of the hub resonant cavity is evaluated based on this curve.
It enables rapid and low-cost evaluation of resonant cavity noise reduction performance during the design phase or after production, eliminating the reliance on vehicle road testing and improving product development efficiency and quality control.
Smart Images
Figure CN122108645A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of wheel hub manufacturing technology, and in particular to an evaluation method, electronic device and medium for the noise reduction performance of a wheel hub resonant cavity. Background Technology
[0002] With the increasing popularity of new energy vehicles, consumers are demanding higher levels of quietness inside the car. Against this backdrop, reducing overall vehicle noise is particularly crucial. Among the sources of vehicle noise, wheel hub noise is a significant component, its root cause being tire cavity resonance: such as... Figure 1 As shown, the wheel assembly includes a tire 1 and a hub 2. The tire 1 and hub 2 are tightly joined to form a sealed tire cavity 3. When the sound wave frequency matches the natural frequency of the tire cavity 3, the sound wave excited by the tire 1 at the contact point (i.e., road excitation) propagates in the forward and reverse directions (i.e., forward sound wave and backward sound wave) in the tire cavity 3 and is superimposed. At some locations, a high-pressure area is formed due to in-phase superposition, and at other locations, a low-pressure area is formed due to out-of-phase cancellation. This waveform with drastic sound pressure fluctuations that does not change with time is called a standing wave (resonance standing wave). When the wheel rotates, this resonance standing wave will generate an unbalanced force on the hub 2, causing the hub 2 to vibrate, and is transmitted to the vehicle through the suspension, forming perceptible resonance noise. To suppress this type of resonance noise, the industry generally arranges multiple specially designed Helmholtz resonance cavities (HR cavities) 2 (e.g., 5) circumferentially on the wheel hub 2. The wheel hub 2 includes a wheel hub base 21 and resonant cavities 4 formed on the wheel hub base 21. The tire cavity 3 includes an annular main cavity 31 and resonant cavities 4. The resonant cavity 4 includes a mouthpiece 41 and a sound cavity 42. The resonant cavity 4 reduces tire cavity resonance noise through acoustic tuning.
[0003] Currently, there is a lack of systematic and independent methods for evaluating the noise reduction effect of resonant cavities. The industry practice is as follows: after completing the design and trial production according to customer requirements, wheel manufacturers directly send the samples to vehicle manufacturers for on-vehicle road testing, and the noise reduction performance is determined based on the results of the on-vehicle road tests. If it does not meet the standards, the design needs to be revised, samples need to be manufactured again, and road tests need to be arranged again.
[0004] However, without a preliminary evaluation of the resonant cavity noise reduction performance, directly delivering prototypes to vehicle road tests can easily lead to a cycle of design, prototyping, road testing, and redesign due to substandard performance. Each iteration relies on lengthy and costly vehicle road tests, which not only prolongs the R&D cycle but also consumes significant human, material, and financial resources, severely impacting product development efficiency and design optimization flexibility. Summary of the Invention
[0005] In view of this, it is necessary to provide an evaluation method, electronic equipment and medium for the noise reduction performance of wheel hub resonators, in order to solve the technical problems of the lack of a pre-process evaluation of the noise reduction performance of resonators in the existing technology, which directly delivers the prototype to the vehicle for road testing, and is prone to cycle of design, prototyping, road testing and redesign due to failure to meet performance standards, resulting in long cycle and high cost.
[0006] To address the aforementioned problems, firstly, this application provides a method for evaluating the noise reduction performance of a wheel hub resonator, applied to a tire cavity, wherein the tire cavity includes an annular main cavity and a plurality of resonator cavities communicating with the main cavity, comprising: The propagation of sound waves within the fetal cavity is equivalent to a plane wave. Based on the obtained geometric parameters of the resonant cavities, the acoustic impedance of each resonant cavity is calculated. Based on the acoustic impedance of each resonator, calculate the total acoustic impedance after they are connected in parallel; The main cavity is equivalent to a straight tube with the same cross-sectional area and length equal to the perimeter of the main cavity. Based on the total acoustic impedance and the obtained geometric parameters of the main cavity, the transmission loss curve of the sound wave as a function of frequency when it propagates one period distance in the straight tube is calculated. The noise reduction performance of the hub resonator is evaluated based on the transmission loss curve.
[0007] In one embodiment, the geometric parameters of the resonant cavity include the actual mouthpiece length, the actual mouthpiece inner diameter, and the actual cavity volume, wherein the actual cavity volume is obtained through the following steps: Obtain the actual mouthpiece length, actual mouthpiece inner diameter, and actual resonant frequency of each resonant cavity; Based on the actual mouthpiece length, actual mouthpiece inner diameter, and actual resonant frequency, the actual cavity volume of each resonant cavity is calculated.
[0008] In one embodiment, the formula for calculating the actual acoustic cavity volume is: ; In the formula, Indicates the volume of the acoustic cavity. Indicates the inner diameter of the mouthpiece. Indicates the length of the mouthpiece. Indicates the resonant frequency. It indicates the speed of sound.
[0009] In one implementation, the formula for calculating the acoustic impedance of each resonant cavity is: ; In the formula, Indicates the first [item] in the fetal cavity The acoustic impedance of a resonant cavity, Represents the imaginary unit. Indicates the angular frequency of the sound wave. Indicates the frequency of the sound wave. , Indicates air density, Indicates the speed of sound. Indicates aerodynamic viscosity, Indicates the length of the mouthpiece. This represents the acoustic end correction factor. Indicates the inner diameter of the mouthpiece. Indicates the volume of the acoustic cavity.
[0010] In one embodiment, the formula for calculating the total acoustic impedance is: ; In the formula, Indicates the total acoustic impedance. Indicates the first in the fetal cavity The acoustic impedance of a resonant cavity, This indicates the total number of resonant cavities.
[0011] In one embodiment, the geometric parameters of the main cavity include the cross-sectional area of the main cavity, and the formula for calculating the transmission loss is: ; In the formula, Indicates the transmission of loss. Indicates air density, Indicates the speed of sound. This indicates the cross-sectional area of the main cavity. This represents the total acoustic impedance.
[0012] In one embodiment, evaluating the noise reduction performance of the hub resonator based on the transmission loss curve includes: calculating the average value of the transmission loss within a preset frequency band in the transmission loss curve, and using the average value as an evaluation index of the noise reduction performance of the hub resonator.
[0013] In one embodiment, the geometric parameters of the resonant cavity include actual geometric parameters and designed geometric parameters. Secondly, this application also provides an electronic device, including a memory and a processor; The memory is used to store programs; The processor, coupled to the memory, is used to execute the program stored in the memory to implement the steps of the above-described method for evaluating the noise reduction performance of the hub resonator.
[0014] Thirdly, this application also provides a computer-readable storage medium storing a program or instructions that, when executed by a processor, implement the steps of the above-described method for evaluating the noise reduction performance of a hub resonator.
[0015] The beneficial effects of this application are as follows: The method for evaluating the noise reduction performance of the wheel hub resonator provided in this application equates the propagation of sound waves in the tire cavity to a plane wave and the complex annular main cavity to a straight pipe with a uniform cross-section. Based on this equivalent condition, by inputting the geometric parameters of the main cavity and the resonator, the transmission loss spectrum curve reflecting the inherent properties of the system can be directly calculated, thereby predicting the noise reduction effect of the resonator after actual vehicle installation in a low-cost and relatively accurate manner. This method eliminates the dependence on vehicle road testing and can quickly and cost-effectively complete the evaluation and qualification of the noise reduction performance of the wheel hub resonator during the design stage or after production, greatly improving product development efficiency and quality controllability. Attached Figure Description
[0016] Figure 1 A schematic diagram of the tire cavity structure is provided for the background art of this application; Figure 2 This is a schematic diagram of the equivalent model structure provided in the embodiments of this application; Figure 3 A flowchart illustrating the method for evaluating the noise reduction performance of a hub resonator provided in an embodiment of this application; Figure 4 A flowchart illustrating the steps for obtaining the actual acoustic cavity volume provided in this application embodiment; Figure 5 A schematic diagram of the transmission loss curve provided for an embodiment of this application; Figure 6 This is a schematic diagram of the structure of the electronic device provided in the embodiments of this application; Reference numerals: 1. Tire; 2. Hub; 21. Hub base; 3. Tire cavity; 31. Main cavity; 4. Resonant cavity; 41. Mouthpiece; 42. Sound cavity; 5. Straight tube. Detailed Implementation
[0017] 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 scope of protection of this application.
[0018] It should be understood that the illustrative drawings are not drawn to scale. The flowcharts used in this application illustrate operations implemented according to some embodiments of this application. It should be understood that the operations in the flowcharts may be implemented out of order, and steps without logical contextual relationships may be reversed or performed simultaneously. Furthermore, those skilled in the art, guided by the content of this application, may add one or more other operations to the flowcharts, or remove one or more operations from the flowcharts. Some block diagrams shown in the drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities may be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor systems and / or microcontroller systems.
[0019] The terms "first," "second," etc., used in the embodiments of this application are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a technical feature specified with "first" or "second" may explicitly or implicitly include at least one of those features. "And / or" describes the relationship between related objects, indicating that three relationships may exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone.
[0020] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.
[0021] This application provides a method for evaluating the noise reduction performance of a hub resonator, an electronic device, and a medium, which are described below.
[0022] To address the technical challenges faced by wheel manufacturers who lack access to digital models of the entire vehicle and suspension system, hindering comprehensive simulation analysis and relying on vehicle road tests, resulting in long development cycles and significant expenditures of human, material, and financial resources, this application takes a different approach by re-examining the fundamental principles for evaluating the noise reduction performance of resonant cavities.
[0023] Research and practice show that the resonant frequency of the tire cavity that causes in-vehicle noise is relatively low, and its sound wave wavelength (approximately 1700 mm) is much larger than the cross-sectional area of the tire cavity and the geometric dimensions of the resonant cavity. Under these conditions, the propagation of sound waves within the tire cavity can be simplified as a plane wave model. Furthermore, due to the large cross-sectional area of the tire cavity, the acoustic impedance is extremely small, and energy attenuation is slow. After embedding the resonant cavity in the wheel hub, the sound wave passes through the same resonant cavity and incurs energy loss every time it propagates through the tire cavity. Therefore, the transmission loss of the sound wave propagating through the tire cavity once can effectively characterize the overall noise reduction capability of the resonant cavity. Further, the wavelength of the resonant sound wave in the tire cavity is much larger than the lateral dimension of the tire cavity. In this case, the sound wave propagation characteristics are mainly affected by the propagation path length and cross-sectional area, and are not sensitive to the geometric curvature of the cavity. The transmission loss of the sound wave propagating through the annular tire cavity once is basically consistent with the transmission loss in a straight tube of equal cross-sectional area and length. Based on the above considerations, this application will... Figure 1 The main cavity 31 shown is equivalent to, as follows: Figure 2 The straight pipe 5 shown.
[0024] To quantitatively evaluate the noise reduction effect of the model, this application establishes a transfer loss function describing the energy attenuation law of sound waves passing through the aforementioned straight tube with a side-branch resonant cavity, the specific expression of which is shown below: ; ; ; ; ; ; In the formula, Indicates the transmission of loss. Indicates air density, Indicates the speed of sound. This indicates the cross-sectional area of the main cavity. Indicates the total acoustic impedance. Indicates the first [item] in the fetal cavity The acoustic impedance of a resonant cavity, Indicates the total number of resonant cavities. Represents the imaginary unit. Indicates the angular frequency of the sound wave. Indicates the frequency of the sound wave. , Indicates air density, Indicates the speed of sound. Indicates aerodynamic viscosity, The acoustic impedance, used to describe damping loss (the denominator in the formula for avoiding transmission loss is zero), is caused by friction generated by air viscosity on the mouthpiece wall, converting sound energy into heat energy. Acoustic impedance is approximately proportional to the length of the mouthpiece and inversely proportional to the cross-sectional area (or the square of the diameter) of the mouthpiece. Indicates the cross-sectional area of the mouthpiece (neck). Indicates the length of the mouthpiece. This represents the acoustic end correction factor (e.g., 0.85). Indicates the inner diameter of the mouthpiece. This indicates the length of the mouthpiece after end correction. Indicates sound quality, used to describe the inertia of the air column inside the mouthpiece; the longer the air column inside the mouthpiece ( Larger), finer ( The smaller the mass (sound mass), the greater the force required to make it vibrate, that is, the greater the inertia (sound mass). Indicates tone compliance, used to describe the elasticity of air within a vocal cavity. This indicates the volume of the acoustic cavity. The larger the volume of the acoustic cavity, the easier it is to compress air, that is, the greater the elasticity (acoustic compliance).
[0025] When applying the above transmission loss function, the transmission loss, i.e. the noise reduction value, can be calculated simply by obtaining the geometric parameters including the mouthpiece length, the mouthpiece inner diameter, and the cavity volume.
[0026] Based on the above considerations, embodiments of this application provide a method for evaluating the noise reduction performance of a hub resonator, such as... Figure 3 As shown, the evaluation methods for the noise reduction performance of the hub resonator include: S301. The propagation of sound waves in the tire cavity is equivalent to a plane wave. Based on the obtained geometric parameters of the resonant cavity, the acoustic impedance of each resonant cavity is calculated.
[0027] It should be noted that the main process in the design phase includes: the customer provides the wheel hub noise reduction requirements, and the wheel hub size and style are confirmed with the customer; after obtaining the customer's requirements, it is determined whether the customer provides the wheel hub noise peak value; if the noise peak value is provided, the geometric parameters of the five resonant cavities of the wheel hub are designed based on the noise peak value; if the noise peak value is not provided, the geometric parameters of the five resonant cavities of the wheel hub are designed using wideband frequency.
[0028] Considering the potential discrepancies between actual and designed geometric parameters, to improve evaluation accuracy, in some embodiments, the geometric parameters of the resonant cavity include both actual and designed geometric parameters. Therefore, during the design phase, the total acoustic impedance can be calculated using the designed geometric parameters of the resonant cavity, and the design transmission loss curve can be calculated based on the total acoustic impedance to evaluate whether the noise reduction performance of the wheel hub resonant cavity meets the requirements. After production, the actual total acoustic impedance can be calculated using the actual geometric parameters of the resonant cavity, and the actual transmission loss curve can be calculated based on the actual total acoustic impedance to evaluate whether the noise reduction performance of the wheel hub resonant cavity meets the requirements.
[0029] Furthermore, the geometric parameters of the resonant cavity typically include the mouthpiece length, the mouthpiece inner diameter, and the cavity volume. Considering that the design values of these geometric parameters are readily available, while the actual cavity volume is difficult to measure directly, the actual resonant frequency can be easily measured. The resonant frequency has a definite mapping relationship with the mouthpiece length, mouthpiece inner diameter, and cavity volume. Therefore, in some embodiments, the geometric parameters of the resonant cavity include the actual mouthpiece length, the actual mouthpiece inner diameter, and the actual cavity volume, such as... Figure 4 As shown, the actual acoustic cavity volume is obtained through the following steps: S401. Obtain the actual mouthpiece length, actual mouthpiece inner diameter, and actual resonant frequency of each resonant cavity.
[0030] S402. Based on the actual mouthpiece length, actual mouthpiece inner diameter, and actual resonant frequency, the actual cavity volume of each resonant cavity is calculated.
[0031] In some embodiments, the acoustic impedance of the resonant cavity The frequency at which the imaginary part is zero is the resonant frequency. (Right now At this frequency, theoretically, the acoustic impedance is at its minimum (close to zero), and sound waves are most easily dissipated through the resonant cavity, resulting in the strongest noise reduction effect. Therefore, the formula for calculating the actual cavity volume can be derived: ; In the formula, Indicates the volume of the acoustic cavity. Indicates the inner diameter of the mouthpiece. Indicates the length of the mouthpiece. Indicates the resonant frequency. It indicates the speed of sound.
[0032] The actual sound cavity volume can be calculated using the above formula from the actual mouthpiece length, the actual mouthpiece inner diameter, and the actual resonant frequency.
[0033] In some embodiments, the formula for calculating the acoustic impedance of each resonant cavity is as follows: ; ; ; ; Based on the above formula, the final formula for calculating the acoustic impedance of each resonant cavity is as follows: ; In the formula, Indicates the first [item] in the fetal cavity The acoustic impedance of a resonant cavity, Represents the imaginary unit. Indicates the angular frequency of the sound wave. Indicates the frequency of the sound wave. , Indicates air density, Indicates the speed of sound. Indicates aerodynamic viscosity, Indicates the length of the mouthpiece. This represents the acoustic end correction factor (e.g., 0.85). Indicates the inner diameter of the mouthpiece. This indicates the length of the mouthpiece after end correction.
[0034] Using the above formula, the acoustic impedance of each resonant cavity can be calculated from the mouthpiece length, mouthpiece inner diameter, and cavity volume.
[0035] S302. Based on the acoustic impedance of each resonator, calculate the total acoustic impedance after they are connected in parallel.
[0036] In some embodiments, the formula for calculating the total acoustic impedance is: ; In the formula, Indicates the total acoustic impedance. Indicates the first in the fetal cavity The acoustic impedance of a resonant cavity, This indicates the total number of resonant cavities.
[0037] Using the above formula, the total acoustic impedance of all parallel resonators can be calculated from the acoustic impedance of each resonator.
[0038] S303. The main cavity is equivalent to a straight tube with the same cross-sectional area and length equal to the perimeter of the main cavity. Based on the total acoustic impedance and the obtained geometric parameters of the main cavity, the transmission loss curve of the sound wave as a function of frequency when it propagates one cycle distance in the straight tube is calculated. The noise reduction performance of the hub resonant cavity is evaluated based on the transmission loss curve.
[0039] In some embodiments, the geometric parameters of the main cavity include the cross-sectional area of the main cavity, and the formula for calculating the transmission loss is: ; In the formula, Indicates the transmission of loss. Indicates air density, Indicates the speed of sound. This indicates the cross-sectional area of the main cavity. This represents the total acoustic impedance.
[0040] Using the above formula, the final transmission loss curve as a function of frequency can be calculated from the cross-sectional area of the main cavity and the total acoustic impedance of the resonant cavity.
[0041] In some embodiments, evaluating the noise reduction performance of the hub resonator based on the transmission loss curve includes: calculating the average value of the transmission loss within a preset frequency band in the transmission loss curve, and using the average value as an evaluation index of the noise reduction performance of the hub resonator.
[0042] It should be noted that the preset frequency band is determined based on whether the customer provides the peak noise level of the wheel hub: if the customer provides the peak noise level, the preset frequency band is centered on that peak noise level (e.g., the preset frequency band is controlled within ±3 of the peak noise level); if the customer does not provide the peak noise level, a wide frequency band is used for the preset frequency band. Finally, it is determined whether the average transmission loss calculated by the software meets the customer's noise reduction standards: if it meets the customer's requirements, production proceeds according to this design; if it does not meet the customer's requirements, a redesign is carried out, and the design is evaluated again after completion.
[0043] For example, the customer requested a noise reduction of 9dB, with a noise peak around 185Hz. The design was carried out according to the customer's requirements, using an engraving process, resulting in a main cavity cross-sectional area of 27500.618mm². 2 There are 5 resonant cavities, each with a designed mouthpiece length of 10mm; the designed inner diameter of the mouthpiece is 6.7mm; the total volume of cavity 1 and cavity 5 is 177817.6mm². 3 The design cavity length for No. 1 and No. 5 is 283.057 mm; the design cavity volume for No. 2, No. 3, and No. 4 is 177818.5 mm². 3 The designed acoustic cavity lengths for cavities 2, 3, and 4 are 283.058 mm; the designed resonant frequencies for cavities 1 through 5 are 191.89 Hz. The actual resonant frequencies of cavities 1 through 5 are 193.8 Hz, 193.8 Hz, 193.8 Hz, 193.8 Hz, and 191.8 Hz, respectively.
[0044] Based on the above data, two curves are obtained: the actual transmission loss curve (red curve) and the design transmission loss curve (blue curve), as follows: Figure 5 As shown, Figure 5The preset frequency band (yellow rectangle) has a starting frequency of 188.89Hz and an ending frequency of 194.89Hz. The calculated average transmission loss of the actual transmission loss curve (i.e., the actual noise reduction value) is 11.9dB, which meets the customer's noise reduction requirements. The wheel hub was manufactured according to these design parameters and given to the customer for road testing. The customer reported a noise reduction result of 6-10dB, which meets the requirements.
[0045] Compared with existing technologies, this application equates the propagation of sound waves in the tire cavity to a plane wave and the complex annular main cavity to a straight pipe with a uniform cross-section. Based on this equivalence, by inputting the geometric parameters of the main cavity and the resonant cavity, the transmission loss spectrum curve reflecting the inherent properties of the system can be directly calculated. This allows for a low-cost and relatively accurate prediction of the noise reduction effect of the resonant cavity after actual vehicle installation. This method eliminates the reliance on vehicle road testing and enables rapid and low-cost evaluation and qualification of the wheel hub resonant cavity's noise reduction performance during the design phase or after production, greatly improving product development efficiency and quality control.
[0046] To verify the predictive performance of this application, a real-vehicle verification was conducted, and the comparison results are shown in Table 1: Table 1 Comparison Results In Table 1, HA1 represents the wheel hub base model. While the wheel hub base model is the same across different projects, the actual geometric parameters of the resonant cavity differ. A vehicle has four wheel assemblies, corresponding to five wheel hubs. 1#, 2#, 3#, and 4# represent the four wheel hubs of a vehicle. The design geometric parameters of the resonant cavity for the four wheel hubs of a vehicle are the same, but the actual geometric parameters differ, resulting in different average values of actual transmission loss (i.e., actual noise reduction). The noise reduction value inside the vehicle during actual testing is obtained from sensors placed in different locations within the vehicle by the OEM. Left front, right front, right rear, right rear, front, and rear represent the sensor placement positions within the vehicle. Different batches of wheel hubs are used in different road tests, resulting in different theoretical and actual geometric parameters of the corresponding resonant cavity. As shown in Table 1, under the condition of determining the peak vehicle noise level, the average value of actual transmission loss calculated by the method in this application, i.e., the actual noise reduction value, matches the average value of actual vehicle testing by more than 85%, thus proving the effectiveness of the evaluation method.
[0047] like Figure 6 As shown, this application also provides an electronic device. This electronic device includes at least a processor 601 and a memory 602.
[0048] Processor 601 may include one or more processing cores, such as a quad-core processor, an octa-core processor, etc. Processor 601 may be implemented using at least one hardware form selected from DSP (Digital Signal Processing), FPGA (Field-Programmable Gate Array), and PLA (Programmable Logic Array). Processor 601 may also include a main processor and a coprocessor. The main processor, also known as a CPU (Central Processing Unit), is used to process data in the wake-up state; the coprocessor is a low-power processor used to process data in the standby state. In some embodiments, processor 601 may integrate a GPU (Graphics Processing Unit), which is responsible for rendering and drawing the content to be displayed on the screen. In some embodiments, processor 601 may also include an AI (Artificial Intelligence) processor, which is used to handle computational operations related to machine learning.
[0049] The memory 602 may include one or more computer-readable storage media, which may be non-transitory. The memory 602 may also include high-speed random access memory and non-volatile memory, such as one or more disk storage devices or flash memory devices. In some embodiments, the non-transitory computer-readable storage media in the memory 602 is used to store at least one instruction, which is executed by the processor 601 to implement the method for evaluating the noise reduction performance of the hub resonator provided in the method embodiments of this application.
[0050] In some embodiments, the electronic device may also optionally include a peripheral device interface and at least one peripheral device. The processor 601, memory 602, and peripheral device interface can be connected via a bus or signal line. Each peripheral device can be connected to the peripheral device interface via a bus, signal line, or circuit board. Indicatively, peripheral devices include, but are not limited to, radio frequency circuits, touch displays, audio circuits, and power supplies.
[0051] Of course, electronic devices may also include fewer or more components, and this embodiment does not limit this.
[0052] Accordingly, this application also provides a computer-readable storage medium for storing computer-readable programs or instructions. When the programs or instructions are executed by a processor, they can implement the steps or functions of the evaluation method for the noise reduction performance of the hub resonator provided in the above-described method embodiments.
[0053] Those skilled in the art will understand that all or part of the processes of the methods described in the above embodiments can be implemented by a computer program instructing related hardware, and the program can be stored in a computer-readable storage medium. The computer-readable storage medium may be a disk, optical disk, read-only memory, or random access memory, etc.
[0054] The above provides a detailed description of the method for evaluating the noise reduction performance of a hub resonator provided in this application. Specific examples have been used to illustrate the principle and implementation of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core idea of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the idea of this application. Therefore, the content of this specification should not be construed as a limitation of this application.
[0055] The above description is merely a preferred embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.
Claims
1. A method for evaluating the noise reduction performance of a hub resonator, characterized in that, Applied to the tire cavity, the tire cavity includes an annular main cavity and several resonant cavities communicating with the main cavity, including: The propagation of sound waves within the fetal cavity is equivalent to a plane wave. Based on the obtained geometric parameters of the resonant cavities, the acoustic impedance of each resonant cavity is calculated. Based on the acoustic impedance of each resonator, calculate the total acoustic impedance after they are connected in parallel; The main cavity is equivalent to a straight tube with the same cross-sectional area and length equal to the perimeter of the main cavity. Based on the total acoustic impedance and the obtained geometric parameters of the main cavity, the transmission loss curve of the sound wave as a function of frequency when it propagates one period distance in the straight tube is calculated. The noise reduction performance of the hub resonator is evaluated based on the transmission loss curve.
2. The method for evaluating the noise reduction performance of the hub resonator according to claim 1, characterized in that, The geometric parameters of the resonant cavity include the actual mouthpiece length, the actual mouthpiece inner diameter, and the actual cavity volume. The actual cavity volume is obtained through the following steps: Obtain the actual mouthpiece length, actual mouthpiece inner diameter, and actual resonant frequency of each resonant cavity; Based on the actual mouthpiece length, actual mouthpiece inner diameter, and actual resonant frequency, the actual cavity volume of each resonant cavity is calculated.
3. The method for evaluating the noise reduction performance of the hub resonator according to claim 2, characterized in that, The formula for calculating the actual acoustic cavity volume is as follows: ； In the formula, Indicates the volume of the acoustic cavity. Indicates the inner diameter of the mouthpiece. Indicates the length of the mouthpiece. Indicates the resonant frequency. It indicates the speed of sound.
4. The method for evaluating the noise reduction performance of the hub resonator according to claim 1, characterized in that, The formula for calculating the acoustic impedance of each resonant cavity is as follows: ； In the formula, Indicates the first [item] in the fetal cavity The acoustic impedance of a resonant cavity, Represents the imaginary unit. Indicates the angular frequency of the sound wave. Indicates the frequency of the sound wave. , Indicates air density, Indicates the speed of sound. Indicates aerodynamic viscosity, Indicates the length of the mouthpiece. This represents the acoustic end correction factor. Indicates the inner diameter of the mouthpiece. Indicates the volume of the acoustic cavity.
5. The method for evaluating the noise reduction performance of the hub resonator according to claim 1, characterized in that, The formula for calculating the total acoustic impedance is: ； In the formula, Indicates the total acoustic impedance. Indicates the first in the fetal cavity The acoustic impedance of a resonant cavity, This indicates the total number of resonant cavities.
6. The method for evaluating the noise reduction performance of the hub resonator according to claim 1, characterized in that, The geometric parameters of the main cavity include the cross-sectional area of the main cavity, and the formula for calculating the transmission loss is: ； In the formula, Indicates the transmission of loss. Indicates air density, Indicates the speed of sound. This indicates the cross-sectional area of the main cavity. This represents the total acoustic impedance.
7. The method for evaluating the noise reduction performance of the hub resonator according to claim 1, characterized in that, The noise reduction performance of the hub resonator is evaluated based on the transmission loss curve, including: calculating the average value of the transmission loss within a preset frequency band in the transmission loss curve, and using the average value as the evaluation index of the noise reduction performance of the hub resonator.
8. The method for evaluating the noise reduction performance of the hub resonator according to claim 1, characterized in that, The geometric parameters of the resonant cavity include actual geometric parameters and design geometric parameters.
9. An electronic device, characterized in that, Including memory and processor; The memory is used to store programs; The processor, coupled to the memory, is used to execute the program stored in the memory to implement the steps of the evaluation method for the noise reduction performance of the hub resonator cavity as described in any one of claims 1 to 8.
10. A computer-readable storage medium, characterized in that, The readable storage medium stores a program or instructions that, when executed by a processor, implement the steps of the evaluation method for the noise reduction performance of the hub resonator cavity as described in any one of claims 1 to 8.