A numerical simulation method, system, terminal and medium for acoustic characteristics of a speaker

Abstract

The present invention discloses a numerical simulation method, system, terminal and medium for acoustic characteristics of a speaker, and relates to the technical field of speaker. The key points of the technical solution are: obtaining the lumped parameters of the speaker; establishing a three-dimensional geometric model diagram of the speaker; establishing a numerical simulation model of the speaker according to the three-dimensional geometric model diagram, material property parameters and coupling parameters; importing the numerical simulation model into a solver, and selecting different research types according to different analysis problems; and selecting full coupling or separation according to the size of the model, and selecting direct or iterative algorithms for solving; obtaining a data set through the solver calculation, and selecting drawing groups and solutions of different dimensions according to the analysis needs to obtain the acoustic characteristic values ​​of the speaker. The present invention analyzes the acoustic characteristics of the speaker, such as sensitivity, directivity, mechanical characteristics of the box structure, etc., shortens the development cycle, reduces development costs, and can have a clearer understanding of the physical process of the speaker working process, which is conducive to improving the quality of speaker design.

Description

Technical Field

[0001] The present invention relates to the technical field of speaker technology, and more specifically, to a numerical simulation method, system, terminal and medium for acoustic characteristics of a speaker. Background Art

[0002] At present, most speaker design methods still use traditional empirical methods, which are generally repeated cycles of sample trial making, testing, improving samples, and retesting. This method has a long development cycle, high cost, and high requirements for test sites and test hardware. With the development of computer technology, the use of numerical simulation analysis methods for auxiliary design has become more and more widespread. Applying numerical simulation analysis methods to speaker design can estimate the performance of speakers in the early stage of sample trial making, thereby speeding up the design progress of speakers and reducing development costs.

[0003] At present, some companies use numerical simulation methods to analyze individual speakers, individual cabinets or sound fields. However, for speakers, their working process involves multiple physical fields and multiple systems, including speaker systems, cabinet solid mechanics, sound fields, etc. Their important acoustic characteristic parameters are also the result of the mutual coupling of multiple physical fields. Therefore, when performing numerical simulation analysis on speakers, the mutual coupling of various systems must be comprehensively considered to achieve higher simulation accuracy.

[0004] However, speakers, especially professional speakers, are often large in size and lack axisymmetry, which makes it impossible to simplify the simulation model symmetrically. When performing multi-physics field coupling numerical calculation simulation, if the method is not properly selected or the processing method is not appropriate, the simulation model will not be able to be solved due to insufficient computing power. Therefore, how to study and design a numerical simulation method, system, terminal and medium for the acoustic characteristics of speakers is an issue that we urgently need to solve. Summary of the invention

[0005] In order to solve the problems that the existing speaker design analyzes the components of the speaker separately, which cannot truly reflect the overall acoustic characteristics of the speaker product, and the problem that the numerical calculation of the multi-physical field coupling of the speaker product is difficult to solve due to the excessive amount of calculation, the purpose of the present invention is to provide a numerical simulation method, system, terminal and medium for the acoustic characteristics of the speaker.

[0006] The above technical objectives of the present invention are achieved through the following technical solutions:

[0007] In a first aspect, a method for numerically simulating acoustic characteristics of a speaker is provided, comprising the following steps:

[0008] S101: Obtaining lumped parameters of the loudspeaker;

[0009] S102: Creating a three-dimensional geometric model of the speaker in three-dimensional drawing software or in numerical simulation analysis software;

[0010] S103: establishing a numerical simulation model of the sound box according to the three-dimensional geometric model diagram, material property parameters and coupling parameters;

[0011] S104: Import the numerical simulation model into the solver, select different research types according to different analysis problems; select full coupling or separation according to the model size, and select direct or iterative algorithm for solving;

[0012] S105: A data set is obtained by calculating the solver, and drawing groups and solutions of different dimensions are selected according to analysis needs to obtain acoustic characteristic values ​​of the speaker.

[0013] Further, the lumped parameters include DC resistance Re, ideal inductance Le in the LR2 inductance loss model, inductance L2 in the LR2 inductance loss model, resistance R2 in the LR2 inductance loss model, vibration mass Mms, vibration mass (excluding pushed air) Mmd, mechanical impedance Rms, flexibility Cms, and magnetic circuit factor BL, which are obtained specifically as follows:

[0014] Directly read the centralized parameter values ​​provided by the speaker supplier through text recognition;

[0015] Alternatively, the lumped parameters can be measured using loudspeaker test equipment.

[0016] Furthermore, the numerical simulation model is established specifically as follows:

[0017] The three-dimensional geometric model diagram is transferred to the numerical calculation software, the three-dimensional geometric model diagram is meshed, and redundant geometric structures such as points, lines, surfaces, and bodies in the three-dimensional geometric model diagram are cleaned up, and an air domain that wraps the speaker is generated at the same time;

[0018] Modify or add material properties of each component in the three-dimensional geometric model diagram according to material property parameters;

[0019] According to the speaker, speaker cabinet, sound field and their mutual coupling, the physical field, the boundary of the physical field and the load are established and set in the simulation environment of the three-dimensional geometric model diagram.

[0020] Furthermore, the loudspeaker physical field integrates the magnetic circuit system and the vibration system through the admittance analogy method;

[0021] The calculation equation of the vibration system is:

[0022] F coil =F R +F M +F K

[0023] F R =R ms ·v

[0024] F M =M ms a=M ms ·j2πfv

[0025]

[0026] In the formula, F coil is the total driving force of the voice coil and magnetic circuit system, F R is the friction force of mechanical and acoustic components, F M is the inertia force of the vibrating mass, F K is the restoring force of the centering support and the folding ring; R ms is the mechanical impedance, v is the speed, M ms is the vibration mass, a is the acceleration, f is the frequency, j is the imaginary unit, K ms is rigidity, x is displacement;

[0027] F coil is the flow variable, similar to the current in electricity; the speed v is the intensity variable, similar to the voltage in electricity; then the relationship between the force, speed, voltage and current of the circuit element is:

[0028] F M =jωM ms. v, F R =R ms v

[0029] I=jωCU,

[0030] By admittance analogy, the speaker is represented by an equivalent circuit, where ω is the angular frequency, I is the current, U is the voltage, C is the capacitance, L is the inductance, and R is the resistance;

[0031] Through the electric-acoustic analogy, the corresponding circuit can be established in the numerical calculation software to set it as the physical field of the speaker; assign values ​​to each component of the circuit, match the working voltage V0 according to the speaker impedance value, and the remaining parameters are obtained by lumped parameters.

[0032] Furthermore, the physical field of the speaker box is a solid mechanics physical field, and the mechanical equation of the speaker is established as:

[0033]

[0034] Then the simple harmonic frequency domain is:

[0035]

[0036] Specifically, the physical field of the speaker is:

[0037] -ik Z =λ

[0038] In the formula, ρ is the density of the speaker box, ω is the angular frequency of the box vibration, u is the speaker vibration displacement vector, S is the box stress tensor, and F v is the volume force on the box (the pressure in the acoustic medium is used as the load), is the phase, k Z is the out-of-plane wave number, λ is the eigenvalue;

[0039] The speaker cabinet is set up as a linear elastic model, and Young's modulus, Poisson's ratio, and density are specified.

[0040] Furthermore, the physical field of the sound field is specifically:

[0041] By wrapping the speaker in the near field with an air domain, the pressure acoustic frequency domain of the near field sound field is analyzed by the finite element method; the near field pressure acoustic frequency domain equation is considered by the control equation of the continuous fluid with no viscosity and heat loss and no flow, and it can be obtained:

[0042]

[0043] p t =p+p b

[0044]

[0045] Select and set the sound source inside the sound field, which is generated by the speaker; and select and set the air density, sound speed, and internal hard sound field boundary;

[0046] For the sound-absorbing cotton laid in the speaker, the porous acoustic Delany-Bazley-Mike model is used to set the flow resistance;

[0047] The pressure acoustics of the far-field sound field is analyzed by the boundary element method, and the acoustic equation is:

[0048]

[0049] p t =p2+p b

[0050]

[0051] Select and set the air density and sound speed;

[0052] In the formula, ρ c is the fluid density (here the air density), P tis the total sound pressure, p and p2 represent the acoustic change of the ambient pressure (acoustic disturbance), p b is the background pressure, q d is a dipole source, ω is the angular frequency of the sound wave, Cc is the speed of sound in the medium (the medium here is air), Q m For a unipolar source, K eq The acoustic wave number includes the ordinary wave number k and the out-of-plane wave number k z and the azimuthal wave number k m .

[0053] Furthermore, the multi-physics field coupling is specifically:

[0054] According to the physical principle of the interaction between the speaker, the sound box and the sound field, the sound field and the box are coupled by sound-structure, and the equation is as follows:

[0055] external:

[0056]

[0057]

[0058] internal:

[0059]

[0060]

[0061]

[0062] In the formula, u tt is the structural acceleration, n is the surface normal direction, pt is the total sound pressure, q d is the acoustic dipole domain sound source, F A is the load acting on the structure (force per unit area), and the up and down designations refer to the two sides of the internal boundary;

[0063] The near-field sound field and the far-field sound field are coupled by acoustic boundary element BEM-finite element FEM, and the equation is as follows:

[0064] p t，bem =p t，fem

[0065] Where P t， bem is the total sound pressure at the boundary element, P t， fem is the total sound pressure at the finite element boundary;

[0066] Specify boundaries between coupled fields.

[0067] In a second aspect, a numerical simulation system for acoustic characteristics of a speaker is provided, comprising:

[0068] A data acquisition module, used for acquiring lumped parameters of the loudspeaker;

[0069] A graphics creation module, used to create a three-dimensional geometric model diagram of the speaker through three-dimensional drawing software or numerical simulation analysis software;

[0070] A model building module is used to build a numerical simulation model of the speaker according to the three-dimensional geometric model diagram, material property parameters and coupling parameters;

[0071] The numerical solution module is used to import the numerical simulation model into the solver, select different research types according to the different analysis problems, and select full coupling or separation according to the model size, and choose direct or iterative algorithm for solution;

[0072] The result analysis module is used to obtain the data set through the solver calculation, and select the drawing groups and solutions of different dimensions according to the analysis needs to obtain the acoustic characteristic values ​​of the speaker.

[0073] In a third aspect, a computer terminal is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, a method for numerically simulating acoustic characteristics of a speaker as described in any one of the first aspects is implemented.

[0074] According to a fourth aspect, a computer-readable medium is provided, on which a computer program is stored. The computer program is executed by a processor to implement a numerical simulation method of acoustic characteristics of a speaker as described in any one of the first aspects.

[0075] Compared with the prior art, the present invention has the following beneficial effects:

[0076] 1. The present invention realizes the analysis of the acoustic characteristics of the speaker, such as sensitivity, directivity, and mechanical characteristics of the box structure, through numerical simulation technology, shortens the development and design cycle of the speaker, reduces the development cost, and can have a clearer understanding of the physical process of the speaker working process, which is conducive to improving the quality of the speaker design;

[0077] 2. When establishing the coupled simulation model, the present invention simplifies the loudspeaker into a circuit physical field analysis through electric-acoustic analogy, thus eliminating a large amount of calculation in solving the calculation. Generally, the concentrated parameters of the loudspeaker are easy to obtain, while the material parameters of the loudspeaker magnetic circuit system and the vibration system are not easy to obtain. Therefore, the electrical analog circuit is more suitable for simulation.

[0078] 3. The present invention couples the loudspeaker, the sound box, the sound-absorbing cotton and the sound field to perform numerical simulation, which comprehensively and truly considers all aspects that affect the acoustic characteristics of the sound box, and can more accurately analyze the acoustic characteristics of the sound box;

[0079] 4. The present invention uses the coupling method of finite element FEM and boundary element BEM when analyzing the sound field of the speaker, which avoids the problem that the volume of the speaker is too large to be calculated when only finite element is used for numerical simulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0080] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings:

[0081] Figure 1 is a flow chart in an embodiment of the present invention;

[0082] Figure 2 is a schematic diagram of a three-dimensional geometric model diagram in an embodiment of the present invention;

[0083] Figure 3 is a schematic diagram of a numerical simulation model in an embodiment of the present invention;

[0084] Figure 4 is a frequency response curve diagram of the speaker in the embodiment of the present invention;

[0085] Figure 5 is the radiation pattern of the speaker in the embodiment of the present invention

[0086] Figure 6 Schematic diagram of the displacement deformation of the speaker box in the embodiment of the present invention

[0087] Figure 7 is an analog circuit schematic diagram of a loudspeaker in an embodiment of the present invention;

[0088] Figure 8 It is a system architecture diagram in an embodiment of the present invention. DETAILED DESCRIPTION

[0089] In order to make the purpose, technical scheme and advantages of the present invention more clearly understood, the following is a summary of the present invention with reference to the embodiments and the accompanying drawings. Figure 1-8 , the present invention is further described in detail. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0090] Embodiment 1: A numerical simulation method for acoustic characteristics of a speaker, such as Figure 1 shown.

[0091] (I) Obtain the lumped parameters of the speaker; the lumped parameters include Re, Le, L2, R2, Mms, Mmd, Rms, Cms, and BL; the lumped parameters are directly read from the lumped parameter values ​​provided by the speaker supplier through text recognition, or measured by speaker test equipment. Taking a speaker as an example, the lumped parameters are shown in Table 1.

[0092] Table 1 Lumped parameters

[0093]

[0094] (ii) Figure 2 As shown, a three-dimensional geometric model diagram of the speaker is established in a three-dimensional drawing software or in a numerical simulation analysis software according to the input lumped parameters; the three-dimensional drawing software includes but is not limited to ProE, Solidworks, and UG software.

[0095] (III) Establish a numerical simulation model of the speaker based on the three-dimensional geometric model diagram, material property parameters and coupling parameters. Figure 3 As shown in the figure, the numerical simulation model is established as follows: the three-dimensional geometric model diagram is transferred to the numerical calculation software COMSOL, the three-dimensional geometric model diagram is meshed, and the redundant geometric structures such as points, lines, surfaces, and bodies in the three-dimensional geometric model diagram are cleaned up, and the air domain that wraps the speaker is generated; the material properties of each component in the three-dimensional geometric model diagram are modified or added according to the material property parameters; the physical field, the boundary of the physical field, and the load are established and set in the simulation environment of the three-dimensional geometric model diagram according to the speaker, the speaker box, the sound field and their mutual coupling. Among them, the mesh division is: specify the mesh unit type and mesh size to generate finite element mesh units. When specifying the unit size, it should be noted that the unit size must be adapted to the shortest wavelength of the analyzed sound wave, and the maximum unit is not greater than one-fifth of the minimum wavelength. The numerical simulation model is meshed, and the maximum unit of the mesh is CO / fmax / 5, where CO is the speed of sound and fmax is the highest frequency of the analysis.

[0096] (1) The loudspeaker physical field integrates the magnetic circuit system and the vibration system through the admittance analogy method.

[0097] The calculation equation of the vibration system is:

[0098] F coil =F R +F M +F K

[0099] F R =R ms ·v

[0100] F M =M ms a=M ms ·j2πfv

[0101]

[0102] In the formula, F coil is the total driving force, F R is the friction force, F M is the inertial force, FK R is the recovery force; ms is the mechanical impedance, v is the speed, M ms is the vibration mass, a is the acceleration, f is the frequency, j is the imaginary unit, K ms is the rigidity and x is the displacement.

[0103] F coil is the flow variable, similar to the current in electricity; the speed v is the intensity variable, similar to the voltage in electricity; then the relationship between the force, speed, voltage and current of the circuit element is:

[0104] F M =jωM ms. v, F R =R ms v

[0105] I=jωCU,

[0106] like Figure 7 As shown in Table 2, by using the electric-acoustic analogy, a corresponding circuit can be established in the numerical calculation software to set it as the physical field of the speaker; assign values ​​to each component of the circuit, V0 is matched according to the speaker impedance value, and the remaining parameters are obtained by lumped parameters.

[0107] Table 2 Initial values ​​and loads of each physical field

[0108]

[0109] (2) The physical field of the speaker box is a solid mechanics physical field, and the mechanical equation of the speaker is established as:

[0110]

[0111] Then the simple harmonic frequency domain is:

[0112]

[0113] Specifically, the physical field of the speaker is:

[0114] -ik Z =λ

[0115] In the formula, ρ is the density of the speaker box, ω is the angular frequency of the box vibration, u is the speaker vibration displacement vector, S is the box stress tensor, and F v is the volume force on the box, is the phase, k Z is the out-of-plane wave number and λ is the eigenvalue.

[0116] The speaker cabinet is set as a linear elastic model, and the Young's modulus, Poisson's ratio, density, and structural loss factor are specified as shown in Table 2.

[0117] (3) The physical field of the acoustic field is as follows: by wrapping the sound box with an air domain in the near field, the pressure acoustic frequency domain of the near field acoustic field is analyzed by the finite element method; the near field pressure acoustic frequency domain equation is considered by the control equation of the continuous fluid with no viscosity and heat loss and no flow, and it can be obtained:

[0118]

[0119] p t =p+p b

[0120]

[0121] Select the sound source inside the sound field, which is generated by the speaker, and set the sound source to the internal normal velocity, whose value is cir.R3_i. Also select the air density, sound speed, and internal hard sound field boundary.

[0122] The porous acoustic Delany-Bazley-Mike model is used for the sound-absorbing cotton laid in the speaker, and the flow resistance Rf is set to 20000Pa*s / m 2 .

[0123] The pressure acoustics of the far-field sound field is analyzed by the boundary element method, and the acoustic equation is:

[0124]

[0125] p t =p2+p b

[0126]

[0127] Select and set the air density and sound speed; where ρ c is the fluid density, P t is the total sound pressure, p and p2 represent the acoustic change of the ambient pressure, p b is the background pressure, q d is a dipole source, ω is the angular frequency of the sound wave, Cc is the speed of sound in the medium, Q m For a unipolar source, K eq The acoustic wave number includes the ordinary wave number k and the out-of-plane wave number k z and the azimuthal wave number k m .

[0128] (4) Multi-physics field coupling According to the physical principle of the interaction between the speaker, the sound box and the sound field, the sound field and the box are coupled by acoustic-structure, and the equation is as follows:

[0129] external:

[0130]

[0131]

[0132] internal:

[0133]

[0134]

[0135]

[0136] In the formula, u tt is the structural acceleration, n is the surface normal direction, pt is the total sound pressure, q d is the acoustic dipole domain sound source, F A It is the load acting on the structure. The up and down signs refer to the two sides of the internal boundary.

[0137] The near-field sound field and the far-field sound field are coupled by acoustic boundary element BEM-finite element FEM, and the equation is as follows:

[0138] p t，bem =p t，fem

[0139] Specify boundaries between coupled fields.

[0140] (IV) Import the numerical simulation model into the solver, select different research types according to the different analysis problems; select full coupling or separation according to the size of the model, and select direct or iterative algorithms for solving; to avoid the problem of non-convergence of calculations, fully coupled and direct solvers can be preferred. If the memory consumption is too large, separation plus iteration can be considered. Taking frequency research as an example, set the frequency point of the calculation. This column uses 1 / 12Oct, select the full coupling method, and use the direct solver MUMPS for solving.

[0141] (V) Obtain the data set through the solver calculation, and select drawing groups and solutions of different dimensions according to the analysis needs to obtain the acoustic characteristic values ​​of the speaker; the acoustic characteristic values ​​include but are not limited to sound pressure distribution, sensitivity, sound pressure isosurfaces, directivity parameters, box stress, and displacement. Because the far-field sound field analysis uses boundary elements, the data set must establish a three-dimensional grid according to the analysis requirements. Take a three-dimensional intercept point 1m in front of the speaker to analyze the sensitivity of the speaker. Its frequency response curve is as follows Figure 4 As shown, establish a polar coordinate drawing group to draw the radiation pattern of the vertical plane and horizontal plane in front of the speaker, such as Figure 5 As shown. Create a 3D plot group to analyze the displacement deformation diagram of the speaker box, such as Figure 6As shown. According to different analysis requirements, sound pressure distribution diagram, sound pressure level distribution diagram, sound pressure isosurface diagram, box stress diagram, etc. can also be established.

[0142] Example 2

[0143] A numerical simulation system for the acoustic characteristics of a speaker, such as Figure 8 As shown, it includes: a data acquisition module, which is used to obtain the lumped parameters of the speaker; a graphic establishment module, which is used to establish a three-dimensional geometric model diagram of the speaker through a three-dimensional drawing software or in a numerical simulation analysis software according to the input lumped parameters; a model establishment module, which is used to establish a numerical simulation model of the speaker according to the three-dimensional geometric model diagram, material property parameters and coupling parameters; a numerical solution module, which is used to import the numerical simulation model into the solver, and select different research types according to different analysis problems; and select full coupling or separation according to the model size, and select direct or iterative algorithms for solving; a result analysis module, which is used to calculate the data set through the solver, and select drawing groups and solutions of different dimensions according to analysis needs to obtain the acoustic characteristic values ​​of the speaker.

[0144] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A numerical simulation method for acoustic characteristics of a speaker, characterized in that: The following steps are involved: S101: Obtaining lumped parameters of the loudspeaker; S102: Creating a three-dimensional geometric model diagram of the speaker by using three-dimensional drawing software or numerical simulation analysis software; S103: establishing a numerical simulation model of the sound box according to the three-dimensional geometric model diagram, material property parameters and coupling parameters; S104: Import the numerical simulation model into the solver, select different research types according to different analysis problems; select full coupling or separation according to the model size, and select direct or iterative algorithm for solving; S105: obtaining a data set through solver calculation, and selecting drawing groups and solutions of different dimensions according to analysis needs to obtain acoustic characteristic values ​​of the speaker; The numerical simulation model is established specifically as follows: The three-dimensional geometric model diagram is transferred to the numerical calculation software, the three-dimensional geometric model diagram is meshed, and the redundant geometric structures in the three-dimensional geometric model diagram are cleaned up. The geometric structures include points, lines, surfaces and bodies, and an air domain that wraps the speaker is generated at the same time; Modify or add material properties of each component in the three-dimensional geometric model diagram according to material property parameters; Establish and set the physical field, load and physical field boundary in the simulation environment of the three-dimensional geometric model diagram according to the speaker, speaker box, sound field and their mutual coupling; The physical field of the loudspeaker integrates the magnetic circuit system and the vibration system through the admittance analogy method; The calculation equation of the vibration system is: F coil =F R +F M +F K F R =R ms ·v F M =M ms ·α=M ms ·j2πfv In the formula, F coil is the total driving force of the voice coil and magnetic circuit system, F R is the friction force of mechanical and acoustic components, F M is the inertia force of the vibrating mass, F K is the restoring force of the centering support and the folding ring; R ms is the mechanical impedance, v is the speed, M ms is the vibration mass, a is the acceleration, f is the frequency, j is the imaginary unit, K ms is rigidity, x is displacement; F coil is the flow variable, similar to the current in electricity; the speed v is the intensity variable, similar to the voltage in electricity; then the relationship between the force, speed, voltage and current of the circuit element is: The speaker is represented by an equivalent circuit, where ω is the angular frequency, I is the current, U is the voltage, C is the capacitance, L is the inductance, and R is the resistance; Through the electric-acoustic analogy, the corresponding circuit can be established in the numerical calculation software to set it as the physical field of the speaker; assign values ​​to each component of the circuit, match the working voltage V0 according to the speaker impedance value, and the remaining parameters are obtained by lumped parameters; The physical field of the speaker box is a solid mechanics physical field, and the mechanical equation for establishing the speaker is: Then the simple harmonic frequency domain is: Specifically, the physical field of the speaker is: In the formula, ρ is the density of the speaker box, ω is the angular frequency of the box vibration, u is the speaker vibration displacement vector, S is the box stress tensor, and F v is the volume force on the box, is the phase, k Z is the out-of-plane wave number, λ is the eigenvalue; The speaker cabinet is set as a linear elastic model, and Young's modulus, Poisson's ratio and density are specified; The physical field of the sound field is specifically: By wrapping the speaker in the near field with an air domain, the pressure acoustic frequency domain of the near field sound field is analyzed by the finite element method; the near field pressure acoustic frequency domain equation is considered by the control equation of the continuous fluid with no viscosity and heat loss and no flow, and it can be obtained: p t =p+p b Select to set the internal sound source of the sound field, which is generated by the speaker; and select to set the air density, sound speed and internal hard sound field boundary; For the sound-absorbing cotton laid in the speaker, the porous acoustic Delany-Bazley-Mike model is used to set the flow resistance; The pressure acoustics of the far-field sound field is analyzed by the boundary element method, and the acoustic equation is: p t =p2+p b Select and set the air density and sound speed; Where ρc is the fluid density, P t is the total sound pressure, p and p2 represent the acoustic change of the ambient pressure, p b is the background pressure, q d is a dipole source, ω is the angular frequency of the sound wave, Cc is the speed of sound in the medium, Q m For a unipolar source, K eq The acoustic wave number includes the ordinary wave number k and the out-of-plane wave number k z and the azimuthal wave number k m ; The speaker, speaker box, sound field and their mutual coupling are specifically: According to the physical principle of the interaction between the speaker, the sound box and the sound field, the sound field and the box are coupled by sound-structure, and the equation is as follows: external: F A ＝ p t n internal: In the formula, u tt is the structural acceleration, n is the surface normal direction, pt is the total sound pressure, q d is the acoustic dipole domain sound source, F A is the load acting on the structure, and the up and down designations refer to the two sides of the internal boundary; The near-field sound field and the far-field sound field are coupled by the acoustic boundary element BEM-finite element FEM, and the equation is as follows: p t ,well=p t ,fem Where P t , bem is the total sound pressure at the boundary element, P t , fem is the total sound pressure at the finite element boundary; Specify boundaries between coupled fields.

2. The method for numerical simulation of acoustic characteristics of a sound box according to claim 1, characterized in that: The lumped parameters include the DC resistance Re, the ideal inductance Le in the LR2 inductance loss model, the inductance L2 in the LR2 inductance loss model, the resistance R2 in the LR2 inductance loss model, the vibration mass Mms, the vibration mass Mmd, the mechanical impedance Rms, the flexibility Cms, and the magnetic circuit factor BL, which are obtained specifically as follows: Directly read the centralized parameter values ​​provided by the speaker supplier through text recognition; Alternatively, the lumped parameters can be measured using loudspeaker test equipment.

3. A numerical simulation system for acoustic characteristics of a speaker, characterized in that: The system application implements a numerical simulation method for the acoustic characteristics of a speaker as claimed in claim 1 or 2, comprising: A data acquisition module, used for acquiring lumped parameters of the loudspeaker; A graphics creation module, used to create a three-dimensional geometric model diagram of the speaker through three-dimensional drawing software or numerical simulation analysis software; A model building module is used to build a numerical simulation model of the speaker according to the three-dimensional geometric model diagram, material property parameters and coupling parameters; The numerical solution module is used to import the numerical simulation model into the solver, select different research types according to the different analysis problems, and select full coupling or separation according to the model size, and choose direct or iterative algorithm for solution; The result analysis module is used to obtain the data set through the solver calculation, and select the drawing groups and solutions of different dimensions according to the analysis needs to obtain the acoustic characteristic values ​​of the speaker.

4. A computer terminal, characterized in that: The invention comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, a numerical simulation method for acoustic characteristics of a speaker as claimed in claim 1 or 2 is implemented.

5. A computer-readable medium, characterized in that: A computer program is stored thereon, and the computer program can be executed by a processor to implement a numerical simulation method for acoustic characteristics of a speaker as claimed in claim 1 or 2.

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