Noise simulation method and equipment for automobile display screen movement mechanism

Abstract

The invention provides an automobile display screen movement mechanism noise simulation method and device, and relates to the field of vibration noise simulation, and the method comprises the steps: obtaining a movement mechanism model; creating an air gap model and a motor air domain model by using the motor geometric model; performing electromagnetic analysis on the air gap model in a motor starting state according to preset motor parameters; performing static analysis and modal analysis on the motion mechanism model; according to the electromagnetic analysis result and the modal analysis result, harmonic response analysis under the motor starting state is carried out; based on the harmonic response analysis result and preset motor air domain model parameters, performing harmonic acoustic analysis on the motor air domain model in a motor starting state to obtain a sound pressure distribution result; and performing data processing on the sound pressure distribution result to obtain a noise simulation result. According to the method, the comprehensive effect of multiple noise sources can be comprehensively considered, coupling analysis is performed on different noise sources such as motor structure vibration noise and air gap vibration noise, and a more comprehensive and accurate noise simulation result is obtained.

Description

Technical Field

[0001] The present invention relates to the field of vibration and noise simulation, and particularly designs a noise simulation method and device for an automotive display movement mechanism. Background Art

[0002] Vibration noise is a phenomenon of sound wave propagation caused by the vibration of an object, usually originating from the operation of mechanical equipment such as motors, gears, pumps, and fans. In these devices, the contact and interaction of components will cause vibration, thereby generating noise. Vibration noise not only affects the performance and lifespan of the equipment, but may also have a negative impact on people's health and quality of life.

[0003] To effectively address the noise problem, it is necessary to conduct noise simulation. Noise simulation uses computer software for simulation and analysis to help us predict the noise level and optimize the design in the early stage of design.

[0004] For the ceiling-mounted display in an automobile, during the opening and closing process, there is a motor on each side driving a lead screw, which in turn drives a slider to move on a slide rail, causing the display to flip. However, the rotation of the motor will generate a certain amount of noise. This noise source involves multiple aspects. The existing technology is relatively one-sided in noise simulation, unable to accurately identify potential noise problems, and it is also difficult to comprehensively optimize the design scheme, thereby improving the performance of the automotive display movement mechanism and the comfort of users. Summary of the Invention

[0005] Based on the above situation, the main purpose of the present invention is to provide a noise simulation method and device for an automotive display movement mechanism.

[0006] To achieve the above purpose, the technical solutions adopted by the present invention are as follows:

[0007] In the first aspect, an embodiment of the present invention discloses a noise simulation method for an automotive display movement mechanism, including:

[0008] Step S100, obtaining a movement mechanism model of the display movement mechanism, where the movement mechanism model includes a motor geometric model, and the motor geometric model is a three-dimensional model of the motor structure, and the motor is used to drive the movement of the automotive display movement mechanism;

[0009] Step S200, creating an air gap model and a motor air domain model using the motor geometric model, where the air gap model is a two-dimensional model obtained by performing 2D processing on the motor geometric model, and the motor air domain model is a three-dimensional model obtained by performing domain processing on the motor geometric model;

[0010] Step S300, perform electromagnetic analysis on the air gap model under the motor starting state according to preset motor parameters, where the preset motor parameters include material settings, boundary condition settings, and mesh division settings;

[0011] Step S400, perform static analysis and modal analysis on the motion mechanism model in sequence to obtain the modal analysis results;

[0012] Step S500, perform harmonic response analysis under the motor starting state according to the electromagnetic analysis results and the modal analysis results;

[0013] Step S600, perform harmonic acoustic analysis on the motor air domain model under the motor starting state based on the harmonic response analysis results and preset motor air domain model parameters to obtain the sound pressure distribution results, where the preset motor air domain model parameters include the acoustic solution domain material of the motor air domain;

[0014] Step S700, perform data processing on the sound pressure distribution results to obtain the noise simulation results.

[0015] Preferably, the motor starting state is the process in which the motor speed gradually increases from zero to the maximum value.

[0016] Preferably, the noise simulation results are the relationship curves between the noise frequency and the sound pressure level.

[0017] Preferably, step S200 includes:

[0018] Step S211, perform 2D conversion on the motor geometric model to obtain a motor model;

[0019] Step S212, simplify the motor model, draw an arc starting from the center of the stator in the simplified motor model and with the inner edge of the rotor as the radius, and circularly array and copy the arc;

[0020] Step S213, cut the arc into line segments according to the motor parameters to obtain an air gap model, where the motor parameters include the tooth width, tooth height, and air gap width of the rotor.

[0021] Preferably, step S200 further includes:

[0022] Step S221, separate the teeth on the rotor in the motor geometric model;

[0023] Step S222, establish an air domain outside the motor geometric model and cut off the separated rotor tooth part to obtain a motor air domain model including the motor peripheral structure.

[0024] Preferably, step S300 includes:

[0025] Step S301: Set the air-gap model according to the preset motor parameters;

[0026] Step S302: Set the air-gap model as the solution model for electromagnetic analysis, and configure the solution information according to the preset solution information;

[0027] Step S302: Self-check and verify the motor parameters and the solution information of the solution model to ensure that the motor parameters and the solution information meet the predetermined standards;

[0028] Step S303: If the self-check is successful, solve and post-process the solution model based on the solution information and the motor parameters to obtain the electromagnetic analysis results, where the electromagnetic analysis results include the solution results and the post-processing results.

[0029] Preferably, step S303 includes:

[0030] If the self-check is successful, solve the solution model based on the solution information and the motor parameters to obtain the solution results of the electromagnetic performance parameters;

[0031] Perform a motor speed scan on the electromagnetic performance parameters to obtain the post-processing results, where the post-processing results include the rotor force and the rotor torque.

[0032] Preferably, step S400 includes:

[0033] Step S401: Set the structural parameters for the motion mechanism model, where the structural parameters include mesh division information, material properties, connection relationships, gravity conditions, and constraint conditions;

[0034] Step S402: Perform a static analysis on the motion mechanism model based on the set structural parameters to obtain the static structural analysis results;

[0035] Step S403: Use the static structural analysis results as the prestress for modal analysis of the motion mechanism model to obtain the modal analysis results.

[0036] Preferably, step S700 includes:

[0037] Step S701: Calculate the residual of the sound pressure distribution result according to the preset parameters, where the preset parameters include frequency limit and time step;

[0038] Step S702: Perform a fast Fourier transform on the result of the residual calculation to obtain the noise simulation result.

[0039] In a first aspect, an embodiment of the present invention discloses a noise simulation device for an automotive display screen movement mechanism, including: a processor and a memory connected to the processor; wherein, the memory stores instructions executable by the processor, and when the instructions are executed by the processor, the processor is caused to execute any one of the noise simulation methods for the automotive display screen movement mechanism.

[0040]

Beneficial effects

[0041] Through a systematic noise simulation procedure, the present invention includes electromagnetic analysis, static analysis, and modal analysis of the motor geometric model, and based on the results of the electromagnetic analysis and modal analysis, harmonic acoustic analysis is further carried out. By combining the electromagnetic analysis in acoustics and the results of the modal analysis in structure, the final noise simulation result can be obtained, which can accurately capture and analyze the complex noise generated by the motor during the process before driving the movement mechanism from multiple dimensions of acoustics and structure, that is, the noise of the motor in the starting state. Traditional noise simulation methods often perform separate simulations for specific noise sources. For example, only the structural vibration noise or air-gap vibration noise of the motor is concerned. Specifically, when multiple noise sources coexist, they may cancel each other out or enhance each other. If only a single noise source is simulated and optimized, this comprehensive effect cannot be accurately captured, resulting in a large difference between the final optimization result and the actual noise situation. The coupling analysis method of this application can comprehensively consider the comprehensive effects of multiple noise sources. By coupling different noise sources such as the structural vibration noise and air-gap vibration noise of the motor, a more comprehensive and accurate noise simulation result can be obtained. This result not only reflects the characteristics of each noise source itself but also reflects the interaction and influence between them. Further, it can ensure that our optimization measures are more targeted and effective, and will better meet the actual needs and usage scenarios of users.

[0042] Other beneficial effects of the present invention will be elaborated in the specific implementation manner through the introduction of specific technical features and technical solutions. Those skilled in the art should be able to understand the beneficial technical effects brought by the technical features and technical solutions through these introductions. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The following will describe the preferred embodiments of a noise simulation method and device for an automotive display screen movement mechanism of the present invention with reference to the accompanying drawings. In the figures:

[0044] Figure 1 is a side view of the display screen according to the present invention;

[0045] Figure 2 is a flowchart of a noise simulation method for an automotive display screen movement mechanism according to the present invention;

[0046] Figure 3 is the noise simulation result diagram according to the present invention;

[0047] Figure 4 is the mesh division result diagram of the moving mechanism model according to the present invention;

[0048] Figure 5 is the mesh sweeping division result diagram of a certain local structure according to the present invention;

[0049] Figure 6 is the local schematic diagram of the sound pressure in the acoustic region according to the present invention;

[0050] Figure 7 is the multi - physical field solution group diagram of the noise simulation according to the present invention. Specific embodiments

[0051] The present invention is described below based on embodiments, but the present invention is not limited to these embodiments. In the following detailed description of the present invention, some specific details are described in detail. To avoid obscuring the essence of the present invention, well - known methods, processes, procedures, and components are not described in detail.

[0052] In addition, those of ordinary skill in the art should understand that the drawings provided herein are for illustrative purposes only, and the drawings are not necessarily drawn to scale.

[0053] Unless the context clearly requires otherwise, the words "including", "comprising", and similar words throughout the specification and claims should be interpreted in an inclusive sense rather than an exclusive or exhaustive sense; that is, the meaning of "including but not limited to".

[0054] In the description of the present invention, it should be understood that terms such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of the present invention, unless otherwise stated, the meaning of "plural" is two or more.

[0055] The object of the noise simulation in the present invention is mainly the drive motor, which can be used to drive the display secondary screen for entertainment on a vehicle or an aircraft. The display secondary screen is a ceiling - mounted display screen installed on the ceiling of a car or an aircraft, and the display screen can be opened and closed by pressing a button. As Figure 1As shown in the figure, there is a motor 1 on each side inside the display screen. The motor is used to drive the motion mechanism of the vehicle display screen. For example, when the button is pressed, the motor 1 rotates to drive the lead screw 2, and the lead screw 2 drives the slider 3 to move on the slide rail. There is a curved rod 4 on each side of the rear shell of the display screen. The slider 3 drives the curved rod 4 to operate, causing the display screen to reverse and close. After closing, the motor stops rotating and the mechanism enters a self-locking state. When the display screen is opened, the motor rotation is the main driving force, and gravity is used as an auxiliary to make the display screen drop naturally. The slider and the curved rod play a role in self-locking. Since the opening and closing processes of the display screen both rely on the self-locking mechanism, this causes additional resistance for the motor when driving the slider. During this process, the electromagnetic force and mechanical vibration generated when the motor starts and accelerates will cause noise.

[0056] Therefore, in the embodiments of the present invention, a method for simulating the noise of a vehicle display screen motion mechanism is provided, which is used to simulate and analyze the noise of the motor in the starting state. In the specific implementation process, for example, ANSYS simulation software can be used for noise simulation, and other simulation software such as ABAQUS and MSC Nastran can also be used for noise simulation analysis.

[0057] As Figure 2 shown, the embodiments of the present invention provide a method for simulating the noise of a vehicle display screen motion mechanism, which specifically includes:

[0058] Step S100, obtaining a motion mechanism model of the display screen motion mechanism. The motion mechanism model includes a motor geometric model, and the motor geometric model is a three-dimensional model of the motor structure. The motor is used to drive the motion mechanism of the vehicle display screen. As Figure 1 shown, the motion mechanism model is a three-dimensional model of the entire display screen including the motor.

[0059] Step S200, creating an air gap model and a motor air domain model by using the motor geometric model. The air gap model is a two-dimensional model obtained by performing 2D processing on the motor geometric model, and the motor air domain model is a three-dimensional model obtained by performing domain processing on the motor geometric model.

[0060] It is necessary to perform a 2D conversion on the three-dimensional model of the motor, so as to convert the three-dimensional motor geometric model into a two-dimensional motor geometric model, and then use the two-dimensional motor geometric model to create an air gap model. For example, a 2D electromagnetic solution module can be used for the conversion of the three-dimensional model. And, a three-dimensional motor air domain model is created by using the three-dimensional motor geometric model. Specifically, the air domain that can enclose the motor can be cut off through interference processing, so as to obtain a motor air domain model including the peripheral structure of the motor.

[0061] Step S300: Conduct electromagnetic analysis on the air-gap model under the motor starting state according to the preset motor parameters, where the preset motor parameters include material settings, boundary condition settings, and mesh division settings.

[0062] After 2D processing and creating the air-gap model, electromagnetic analysis can be performed on the air-gap model according to the preset motor parameters. Among them, the motor parameters can include, for example, the material properties of each structure of the motor, the boundary conditions of the magnetic field to ensure the accuracy of magnetic field calculation, mesh division of the air-gap model. Through mesh division, the continuous physical field is discretized into a series of small units for easy numerical calculation. During the mesh division process, the meshes of the rotor and tooth parts can also be encrypted to more accurately capture the electromagnetic field distribution in these areas and improve the accuracy of simulation analysis.

[0063] Step S400: Perform static analysis and modal analysis on the motion mechanism model in sequence to obtain the modal analysis results.

[0064] Perform static analysis and modal analysis on the three-dimensional structure model of the entire display screen including the motor in sequence.

[0065] Step S500: Conduct harmonic response analysis under the motor starting state according to the electromagnetic analysis results and modal analysis results.

[0066] Harmonic response analysis combines the results of electromagnetic analysis and modal analysis, aiming to comprehensively evaluate the noise generated by the motor during its operation.

[0067] Step S600: Conduct harmonic acoustic analysis on the motor air domain model under the motor starting state based on the harmonic response analysis results and the preset motor air domain model parameters to obtain the sound pressure distribution results. The preset motor air domain model parameters include the material of the acoustic solution domain of the motor air domain.

[0068] The actual operating environment of the motor of the present invention is usually in the air. Therefore, in order to simulate and analyze the propagation and influence of the noise generated during motor operation in the real environment, acoustic analysis needs to be carried out in the air domain, and the results obtained in this way are more valuable for practical applications and can more accurately reflect the influence of motor noise on the surrounding environment and equipment.

[0069] Step S700: Process the sound pressure distribution results to obtain the noise simulation results.

[0070] Furthermore, the noise simulation result is a relationship curve between the noise frequency and the sound pressure level. Figure 3 For the noise simulation result graph, the abscissa is the noise frequency (HZ) of Frequency, and the ordinate is the sound pressure (DB) of Sound Pressure Level.

[0071] In this embodiment, electromagnetic analysis, static analysis, and modal analysis are performed on the motor geometric model, and harmonic acoustic analysis is further performed based on the results of the electromagnetic analysis and modal analysis. By combining the electromagnetic analysis results in terms of acoustics and the modal analysis results in terms of structure, the final noise simulation results can be obtained, which can accurately capture and analyze the complex noise generated by the motor during the process before driving the motion mechanism to move from both the acoustic and structural dimensions, that is, the noise of the motor in the starting state. By coupling and analyzing different noise sources such as the motor structure vibration noise and the air-gap vibration noise, a more comprehensive and accurate noise simulation result can be obtained.

[0072] In one embodiment, the starting state of the motor is the process in which the motor speed gradually increases from zero to the maximum value.

[0073] The core of the present invention lies in deeply analyzing the noise situation of the motor before driving the automotive display motion mechanism to start moving, which is a key link that may be easily overlooked in conventional designs. At this specific stage, the motor is the main noise source because it is undergoing a drastic change from rest to high-speed rotation. In order to accurately analyze the noise of the motor at this stage, a high-precision simulation model is adopted, which can accurately simulate the motor noise and also help solve potential noise problems and improve the user experience.

[0074] In one embodiment, step S200 includes:

[0075] Step S211: Convert the motor geometric model into a 2D model to obtain a motor model. The 2D model can retain the key geometric features of the motor, reduce the computational complexity, and thus improve the efficiency of subsequent analysis.

[0076] Step S212: Simplify the motor model. Starting from the center of the stator in the simplified motor model, draw an arc with the inner edge of the rotor as the radius, and circularly array and copy the arc.

[0077] Simplify the motor model to obtain the stator and rotor structures in the motor. In the specific implementation process, the entire motor model can be simplified to obtain the stator and rotor structures of the complete motor, or only a part of the motor model can be simplified to obtain the stator and rotor structures of a part of the motor. For example, one-eighth of the motor model can be simplified to obtain the stator and rotor structures of one-eighth of the motor. Using a part of the motor structure for modeling helps simplify the calculation and improve the simulation efficiency.

[0078] Draw an arc on a simplified motor model. The drawn arc represents the air gap between the stator and rotor of the motor. The air gap is an important factor affecting the electromagnetic performance of the motor, and its geometric shape directly affects the distribution of the electromagnetic field. After drawing a single air gap arc, use the circular array replication function to generate multiple arcs at equal intervals to form a complete air gap structure. This method ensures the consistency of the symmetry of the air gap during the rotation of the motor and provides a basis for the electromagnetic calculation of the motor.

[0079] Step S213, cut the arc into line segments according to the motor parameters to obtain an air gap model. The motor parameters include the tooth width, tooth height, and air gap width of the rotor.

[0080] By cutting the air gap arc in combination with the actual tooth width, tooth height, and air gap width of the rotor, the actual geometric characteristics of the air gap can be more accurately reflected, thereby improving the accuracy of the air gap model and making the final simulation results more accurate.

[0081] In one embodiment, step S200 further includes:

[0082] Step S221, separate the teeth on the rotor in the motor geometric model.

[0083] Step S222, establish an air domain outside the motor geometric model, and remove the separated rotor tooth part to obtain a motor air domain model including the peripheral structure of the motor.

[0084] Specifically, first separate the teeth of the rotor on the motor, and then establish an air domain outside the motor that can completely enclose the motor structure. The air domain is usually in a simple shape, such as a rectangle or a circle. In this embodiment, a circle is used. Then, through interference processing, a part of the air domain is removed, that is, the "difference" or "subtract" function in Boolean operations is used to remove the separated rotor tooth part of the motor from the air domain. The remaining part of the air domain constitutes the air domain model including the peripheral structure of the motor. This model can simulate the propagation of noise sound waves in the motor and the surrounding air.

[0085] In one embodiment, step S300 includes:

[0086] Step S301, set the air gap model according to the preset motor parameters.

[0087] The air-gap model can be set up according to the material settings, boundary condition settings, and mesh generation settings to construct a complete and accurate air-gap model. In the material settings, appropriate material properties are assigned to different components (such as the stator, rotor, and air gap) to ensure that the response of the electromagnetic field in each material is real and reliable; through the definition of boundary conditions, it is ensured that the model can accurately reflect the physical environment during the simulation process; and mesh generation is achieved by decomposing the model into computational cells of appropriate sizes. A reasonable mesh generation can improve the solution accuracy and computational efficiency.

[0088] Step S302: Set the air-gap model as the solution model for electromagnetic analysis and configure the solution information according to the preset solution information.

[0089] Set the air-gap model as the solution model. For example, a 2D electromagnetic solution module can be used for electromagnetic analysis, and solution parameters such as the solution algorithm, solution accuracy, and time step are configured.

[0090] Step S302: Self-check and verify the motor parameters and solution information of the solution model to ensure that the motor parameters and solution information meet the predetermined standards.

[0091] The input motor parameters and solution information will be verified to check whether these parameters meet the standards. For example, a 2D electromagnetic solution module can be used for verification. When verifying, it is necessary to check whether the motor parameters are within the allowable range, whether the solution settings are reasonable, and whether the properties of the materials used are correct. If they meet the standards, it indicates that the self-check is successful.

[0092] Step S303: If the self-check is successful, solve and post-process the solution model based on the solution information and motor parameters to obtain the electromagnetic analysis results. For example, a 2D electromagnetic solution module can be used for electromagnetic analysis, and the electromagnetic analysis results include the solution results and the post-processing results.

[0093] If the self-check passes, electromagnetic analysis is performed. Among them, the solution result is the electromagnetic distribution result of the motor.

[0094] In this embodiment, by setting and verifying the motor parameters and solution information, it is ensured that the constructed air-gap model can accurately reflect the characteristics of the actual motor. First, the air-gap model is set up through the motor parameters to create a simulation model that meets the design standards; second, the model is configured as the solution model for electromagnetic analysis and self-checked to ensure the validity of the input parameters and solution information and avoid potential errors; finally, after the self-check is successful, electromagnetic solution is performed, and analysis results are generated through post-processing to provide accurate electromagnetic field distribution data.

[0095] Further, step S303 includes:

[0096] If the self-check is successful, the solution model is solved based on the solution information and motor parameters to obtain the solution results of the electromagnetic performance parameters.

[0097] After the self-check is successful, an electromagnetic analysis is performed on the pre-constructed solution model according to the solution information and motor parameters. This process includes numerically solving the electromagnetic field in the model to obtain detailed results of electromagnetic performance parameters such as magnetic field distribution, torque, and power loss.

[0098] Perform a motor speed scan on the electromagnetic performance parameters to obtain the post-processing results, which include rotor force and rotor torque.

[0099] Based on the solved electromagnetic performance parameters, a speed scan is performed on the motor, that is, the performance analysis is performed again at various speeds (from zero to the maximum speed) when the motor is in the starting state. The speed scan can help obtain the performance of the motor at different speeds, especially the changes in rotor force and rotor torque.

[0100] In this embodiment, the solution model is first self-checked and the model is solved using the solution information and motor parameters to obtain the electromagnetic performance parameters, and then a comprehensive motor speed scan is performed to analyze key performances such as rotor force and rotor torque at different speeds for harmonic response analysis.

[0101] In one embodiment, step S400 includes:

[0102] Step S401, set the structural parameters for the motion mechanism model, and the structural parameters include mesh division information, material properties, connection relationships, gravity conditions, and constraint conditions.

[0103] Specifically, parameter settings are performed for the three-dimensional motion mechanism model of the entire display screen including the motor structure. For example, set the physical preference for mesh division to: Mechanical. Set the maximum size of the mesh element to: 5 mm. Use adaptive size adjustment and set the adaptive resolution coefficient of mesh division to 7. Start the mesh feature clearing setting and set the minimum feature clearing size to 0.1 mm. Select fast mesh division and select the large-scale span angle center distribution. Set the mesh quality error limit value to: Strong Mechanical, and set the mesh connection smooth quality to medium. Enable the advanced mesh division setting and select topological inspection and shrinkage tolerance. After the mesh division information is set, a mesh diagram of the three-dimensional motion mechanism model as shown in Figure 4 will be obtained.

[0104] Add encryption control to the local mesh of the thin plate structure and add sweep method division. Check the glass, TFT, circuit board, film material, and light guide plate in the display screen structure and set the sweep division. Set the automatic Src / Trg division settings and set the quadrilateral / triangle division method as the highest priority. Set the number of partitions to 2 to ensure that the minimum number of layers of the unilateral mesh is not less than 2. After the sweep method division, the following will be obtained as Figure 5 a certain local structure diagram as shown.

[0105] Material property setting: It is necessary to set the material properties of each component in the model according to the physical property parameters of the actual material (such as density, elastic modulus, Poisson's ratio, etc.).

[0106] Establish connections between parts: In the original structure, there are strong connections such as welding and glue bonding, and contact: binding replacement can be selected; in the original structure, there are bolt and screw connections, and beam connection replacement can be selected; in the original structure, there are snap fits, limit connections, etc., and friction, frictionless, and no separation replacements can be selected according to the situation.

[0107] Select the contact active contact surface and select the target geometric surface. Set the contact type to binding, and check the program control for behavior and trimming contact. In the advanced contact settings, set the generalized Lagrange method, enable the small sliding setting parameters, detect the calculation convergence at the Gauss points, and set the penetration tolerance value to 0.158 mm. Start the elastic modulus tolerance factor and set the coefficient to 0.3. Select to update the strength actively each time, and set the absolute normal stiffness to 15. Set the contact setting search radius to 1 mm.

[0108] Add gravity condition: Simulate the static state of the display screen affected by the gravity factor during the actual installation process in the vehicle.

[0109] Add constraint conditions: Add remote displacement to the limit surface of the limit post at the installation point of the rear shell, and limit the degrees of freedom of remote displacement A: Y and Z translation, X rotation; limit the degrees of freedom of remote displacement B: Z translation, X and Y rotation; limit remote displacement C: Y translation, X and Z rotation; limit the degrees of freedom of remote displacement D: all degrees of freedom.

[0110] Step S402, perform static analysis on the motion mechanism model based on the set structural parameters to obtain the static structural analysis results.

[0111] When performing static analysis, analysis settings need to be carried out. The static structural analysis setting parameters are as follows: number of steps 1, current step 1, step end time 1S. Check the automatic time step, set the initial sub-step to 200, set the minimum sub-step to 25, and set the maximum sub-step to 100000. Turn off the weak spring setting and enable large deflection. Turn off the inertial release and quasi-static solution. Turn off the Coriolis effect and set the program control restart point. Turn off the contact distribution and inverse options, and enable the output of stress, strain, and deformation quantity settings.

[0112] Step S403: Use the static structure analysis result as the prestress for modal analysis of the motion mechanism model to obtain the modal analysis result.

[0113] When performing modal analysis, it is necessary to check the static structure in the prestress, select the prestress method to use the result of the static structure as the prestress applied to the mode, set the maximum modal order to 200, select to solve the mode in the frequency range of 0 - 2000 Hz, turn off the damping setting, and turn off the Coriolis effect and the CAMPBELL diagram.

[0114] The modal analysis result provides the modal frequency data of the motor in different directions (X, Y, Z). The influence degree of the corresponding vibration mode on the overall vibration response of the motor can be confirmed according to the modal contribution degree. Harmonic response can be carried out using these contribution degrees (such as high - impact modes greater than 70%). By focusing on these high - contribution modes, the dynamic response of the motor can be more accurately simulated and analyzed.

[0115] Furthermore, step 500 specifically includes: When performing harmonic response analysis, settings need to be made for the harmonic response analysis. The harmonic response load comes from, for example, the multi - RPM setting of the 2D electromagnetic solution module. Therefore, if you want to fully read the motor load of, for example, the 2D electromagnetic solution module, multiple - step solutions are required. Set the multi - RPM setting option, set the number of steps to 5, set ITNFS = 5000, which is the upper limit value of the maximum motor speed. Set the maximum and minimum frequency range of the stepper motor to 0 - 12500 HZ, and set the distributed solution interval to 75. The above settings will generate a multi - RPM table on the right.

[0116] Harmonic response analysis needs to import and set the rotor force and rotor torque obtained from electromagnetic analysis as loads, that is, apply a force and a torque to each inner surface of the motor rotor respectively. Due to the uneven electromagnetic influence at the winding positions of the motor coils, the results of each application surface are different.

[0117] In one embodiment, step S600 of harmonic acoustic analysis includes:

[0118] Set the material for the acoustic region of the motor air domain; set the material of the acoustic solution domain to air, and turn on the nonlinear effect and the thermal strain effect.

[0119] In addition, it is also necessary to mesh the motor air domain. The requirements for mesh encryption in this solution domain are the same as those for adding encryption control to the local mesh of the thin - sheet structure in the motor geometry. The mesh division result is as Figure 6 shown.

[0120] It is also necessary to make analysis settings for harmonic acoustic analysis, and these settings are the same as those for harmonic response analysis.

[0121] The finally obtained sound pressure distribution results include the sound pressure in the acoustic region, sound pressure level, frequency response results, and waterfall plot. The waterfall plot can read the multi-RPM solution information to obtain a numerical change relationship chart according to the change in rotational speed.

[0122] The sound pressure distribution results obtained by harmonic acoustics can be exported as an acoustic file, and the format of the acoustic file can be, for example, an ANSYS SOUND file.

[0123] In one embodiment, step S700 includes:

[0124] Step S701, performing a residual calculation on the sound pressure distribution results according to preset parameters, where the preset parameters include frequency limit and time step.

[0125] Step S702, performing a fast Fourier transform on the result of the residual calculation to obtain a noise simulation result.

[0126] Specifically, an acoustic file can be used to start the FWH noise analysis model setting. To simulate the cutting, separation, impact, and extrusion of the air layers inside and outside the motor during motor rotation, the noise source is defined as the rotating wall surface.

[0127] Then set the signal processing time step. Since the road condition excitation received during vehicle driving is generally not higher than 2000HZ, the noise problem when the noise reaches 2000HZ is checked. Given that frequency is the reciprocal of time, the distance traveled by a sound wave is 1 / 20000HZ = 0.00005s. To accurately calculate the data of grid points on each sound wave wavelength, DT = 0.00001s is required to keep the comparison between the sound pressure per revolution of the motor rotation and the theoretical value within a certain range, such as within 0.23%.

[0128] Taking the example of the motor RPM = 3600, we have:

[0129] 3600 RPM → 60 rev. / s → 1 / 60 s / rev. = 0.016666 s (the number of seconds required for one revolution)

[0130] Therefore:

[0131] Number of Time Steps (time step) = 0.016666 s / 0.00001 s = 1667

[0132] Therefore, using the acoustic file ANSYS SOUND, a residual calculation is performed on the sound pressure distribution results according to the frequency and time step to obtain the acoustic calculation residual result.

[0133] Then, perform a fast Fourier transform on the result of the residual calculation. Since the analysis data obtained by SOUND cannot be directly converted into audio and convenient-to-view icons, it is necessary to perform post-processing of the results through the fast Fourier transform FFT. View the output chart ( Figure 3 ), with the X-axis in HZ and the Y-axis in DB. Since the sound source result is inconsistent with the noise actually heard by the human ear, it is necessary to consider the attenuation problem in the air and the secondary refraction in the propagation path. In fact, the path of sound propagation to the human ear is inconsistent with the path of the sound source spreading to the human body surface. SOUND internally supports this information processing.

[0134] The present invention can also match the verification result of the structural strength test with the simulation result. If the matching degree is within a certain range, then the acoustic requirements in the actual use of the simulation model are within an acceptable range and are more in line with the actual situation, so as to verify the accuracy of the simulation result.

[0135] Through the above steps, ANSYS can be used to complete the noise analysis of the automotive display screen. It can accurately capture and analyze the complex noise generated during the process before the motor drives the motion mechanism to move from multiple dimensions of acoustics and structure, that is, the noise of the motor in the starting state.

[0136] Finally, the structure of the display screen can be optimized according to the noise simulation results. For example, use foam at the joints of non-moving mechanism parts to reduce the friction noise between parts; add more reinforcing ribs and force conduction methods at the joints between the motor and the moving mechanism to attenuate the transmission of motor excitation; intervene in the simulation test at the initial stage of product design to ensure that the design meets the requirements and reduce the modification cost.

[0137] To Figure 7 explain the noise simulation of the present invention again, Figure 7A multi - physical - field solution group for noise simulation, in which the motor geometric model 5 is imported into the 2D electromagnetic solution module 6 for electromagnetic analysis; the motion mechanism model 7 is imported into the static analysis module 8 for static analysis, and then the static analysis result is used as the setting information of the modal analysis module 9 for modal analysis to calculate the natural frequency where the motion mechanism model is located. Then, based on the modal analysis result, the harmonic response analysis module 10 uses the modal superposition method within the modal solution range to solve, and imports the rotor force and rotor torque of the 2D electromagnetic solution module 6 as external loads for harmonic response analysis. The harmonic response analysis result obtained in the harmonic response analysis module 10 will be the most important external excitation condition for harmonic acoustic analysis. Then, based on the harmonic response analysis result, a harmonic acoustic analysis module 11 is established, and the motor air domain model 12 and the harmonic response analysis result are used as the setting information of the harmonic acoustic analysis module 11 for harmonic acoustic analysis. Considering only the case of motor noise, there is no need to divide the entire display screen model and the surrounding structure into the acoustic solution. Therefore, only the rotational noise of the motor alone is considered. Thus, only the motor air domain model needs to be imported for harmonic acoustic analysis. Finally, the harmonic acoustic analysis module 11 performs harmonic acoustic analysis on the motor air domain model 12 under the motor starting state according to the harmonic response analysis result and the preset motor air domain model parameters, and the sound pressure distribution result can be obtained, that is, the noise of the motor under the starting state.

[0138] According to a method and device for noise simulation of an automotive display screen motion mechanism disclosed in the present invention, through a systematic noise simulation step, including electromagnetic analysis, static analysis, and modal analysis of the motor geometric model, and based on the electromagnetic analysis result and the modal analysis result, harmonic acoustic analysis is further carried out. By combining the electromagnetic analysis in acoustics and the modal analysis result in structure, the final noise simulation result can be obtained, which can accurately capture and analyze the complex noise generated during the process before the motor drives the motion mechanism to move from multiple dimensions of acoustics and structure, that is, the noise of the motor under the starting state. Traditional noise simulation methods often perform separate simulations for specific noise sources. For example, only the structural vibration noise or air - gap vibration noise of the motor is concerned. Specifically, when multiple noise sources exist simultaneously, they may cancel each other out or enhance each other. If only a single noise source is simulated and optimized, this comprehensive effect cannot be accurately captured, resulting in a large difference between the final optimization result and the actual noise situation. The coupling analysis method of this application can comprehensively consider the comprehensive effect of multiple noise sources. By coupling and analyzing different noise sources such as the structural vibration noise and air - gap vibration noise of the motor, a more comprehensive and accurate noise simulation result can be obtained. This result not only reflects the characteristics of each noise source itself but also reflects the interaction and influence between them. Further, it can ensure that our optimization measures are more targeted and effective, and will be more in line with the actual needs and usage scenarios of users.

[0139] Those skilled in the art can understand that, on the premise of no conflict, the above-mentioned preferred solutions can be freely combined and superimposed. Among them, the flowcharts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of systems, methods, and computer program products according to various embodiments of the present disclosure. In this regard, each block in the flowchart or block diagram may represent a module, a program segment, or a part of code, and this module, program segment, or part of code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order from that marked in the accompanying drawings. For example, two consecutive blocks shown may actually be executed substantially in parallel, and they may sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and / or flowchart, as well as the combination of blocks in the block diagram and / or flowchart, can be implemented by a dedicated hardware-based system for performing the specified functions or operations, or can be implemented by a combination of dedicated hardware and computer instructions. The numbering of each step in this article is only for convenience of description and reference, and is not used to limit the order before and after. The specific execution order is determined by the technology itself, and those skilled in the art can determine various permitted and reasonable orders according to the technology itself.

[0140] It should be noted that in the present invention, the step numbers (letter or number numbers) are used to refer to certain specific method steps only for the purpose of convenient description and brevity, and by no means to limit the order of these method steps by letters or numbers. Those skilled in the art can understand that the order of relevant method steps should be determined by the technology itself and should not be unduly restricted by the existence of step numbers. Those skilled in the art can determine various permitted and reasonable step orders according to the technology itself.

[0141] Those skilled in the art can understand that, on the premise of no conflict, the above-mentioned preferred solutions can be freely combined and superimposed.

[0142] It should be understood that the above embodiments are merely exemplary and not restrictive. Without departing from the basic principles of the present invention, various obvious or equivalent modifications or substitutions made by those skilled in the art to the above details will be included within the scope of the claims of the present invention.

Claims

1. A method for simulating the noise of a motion mechanism of an automotive display screen, characterized in that, Including: Step S100, obtaining a motion mechanism model of the display screen motion mechanism, where the motion mechanism model includes a motor geometric model, and the motor geometric model is a three-dimensional model of the motor structure, and the motor is used to drive the motion of the vehicle display screen motion mechanism; Step S200, creating an air gap model and a motor air domain model using the motor geometric model, where the air gap model is a two-dimensional model obtained by performing 2D processing on the motor geometric model, and the motor air domain model is a three-dimensional model obtained by performing domain processing on the motor geometric model; Step S300, performing electromagnetic analysis on the air gap model in the motor starting state according to preset motor parameters, where the preset motor parameters include material setting, boundary condition setting, and mesh division setting; Step S400, performing static analysis and modal analysis on the motion mechanism model in sequence to obtain a modal analysis result; Step S500, performing harmonic response analysis in the motor starting state according to the electromagnetic analysis result and the modal analysis result; Step S600, performing harmonic acoustic analysis on the motor air domain model in the motor starting state based on the harmonic response analysis result and preset motor air domain model parameters to obtain a sound pressure distribution result, where the preset motor air domain model parameters include the acoustic solution domain material of the motor air domain; Step S700, performing data processing on the sound pressure distribution result to obtain a noise simulation result.

2. The method for simulating the noise of the automotive display motion mechanism according to claim 1, wherein The motor starting state is the process in which the motor speed gradually increases from zero to the maximum value.

3. The noise simulation method for the automotive display motion mechanism according to claim 1, wherein The noise simulation result is a relationship curve between noise frequency and sound pressure level.

4. The method for simulating the noise of the automotive display movement mechanism according to claim 1, characterized in that Step S200 includes: Step S211, performing 2D conversion on the motor geometric model to obtain a motor model; Step S212, simplifying the motor model, starting from the stator center of the simplified motor model, drawing an arc with the inner edge of the rotor as the radius, and circularly arraying and copying the arc; Step S213, cutting the arc into line segments according to motor parameters to obtain an air gap model, where the motor parameters include the tooth width, tooth height, and air gap width of the rotor.

5. The method for simulating the noise of the automotive display motion mechanism according to claim 1, wherein Step S200 further includes: Step S221, separating the teeth on the rotor in the motor geometric model; Step S222, establishing an air domain outside the motor geometric model and cutting off the separated rotor tooth part to obtain a motor air domain model including the motor peripheral structure.

6. The method for simulating the noise of the automotive display motion mechanism according to claim 1, wherein, Step S300 includes: Step S301, setting the air gap model according to preset motor parameters; Step S302, setting the air gap model as a solution model for electromagnetic analysis and configuring solution information according to preset solution information; Step S302, performing self-check verification on the motor parameters and the solution information of the solution model to ensure that the motor parameters and the solution information meet the predetermined standards; Step S303, if the self-check is successful, then solving and post-processing the solution model based on the solution information and the motor parameters to obtain an electromagnetic analysis result, where the electromagnetic analysis result includes a solution result and a post-processing result.

7. The method for simulating the noise of the automotive display motion mechanism according to claim 6, wherein Step S303 includes: If the self-check is successful, the solution model is solved based on the solution information and the motor parameters to obtain the solution result of the electromagnetic performance parameters; The electromagnetic performance parameters are scanned for the motor speed to obtain a post-processing result, and the post-processing result includes the rotor force and the rotor torque.

8. The method for simulating the noise of the automotive display movement mechanism according to claim 1, wherein Step S400 includes: Step S401, setting structural parameters for the motion mechanism model, where the structural parameters include mesh division information, material properties, connection relationships, gravity conditions, and constraint conditions; Step S402, performing a static analysis on the motion mechanism model based on the set structural parameters to obtain a static structural analysis result; Step S403, using the static structural analysis result as the prestress for modal analysis to perform modal analysis on the motion mechanism model to obtain a modal analysis result.

9. The method for simulating the noise of the automotive display movement mechanism according to claim 1, wherein Step S700 includes: Step S701, calculating the residual of the sound pressure distribution result according to preset parameters, where the preset parameters include frequency limits and time steps; Step S702, performing a fast Fourier transform on the result of the residual calculation to obtain a noise simulation result.

10. An automobile display screen movement mechanism noise simulation device, characterized in that, Includes: A processor and a memory connected to the processor; wherein, the memory stores instructions executable by the processor, and the instructions are executed by the processor to enable the processor to execute the method for simulating the noise of the automotive display motion mechanism according to any one of claims 1-9.

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