A bidirectional broadband fluid-structure coupling simulation method for hypersonic turbulent vibration noise

Abstract

The present invention discloses a method for simulating bidirectional broadband fluid-solid coupling of hypersonic turbulent vibration noise, which belongs to the field of fluid noise vibration coupling, and includes the following steps: calculating the average force load of the fluid, unsteady medium-low frequency and high-frequency pulsating pressure loads by combining computational fluid dynamics (RANS, LES, DES) with a turbulent broadband noise simulation algorithm (UDSRFG); solving the thermal conduction of the solid structure and the thermodynamic response and deformation under broadband loads by smooth particle dynamics, i.e. SPH; and realizing the bidirectional transfer algorithm of fluid and solid physical quantities to calculate the bidirectional broadband fluid-solid coupling of hypersonic speed. The present invention is based on a high-precision fluid finite volume program and a solid smooth particle dynamics method to simultaneously consider the interaction between the two physical fields of fluid and structure, and combines computational fluid dynamics and computational structural dynamics to establish a fluid-solid bidirectional coupling vibration model that considers the elastic vibration feedback of the wall, thereby overcoming the difficulties of the current bidirectional broadband fluid-solid coupling vibration noise simulation.

Description

Technical Field

[0001] The invention relates to the technical field of fluid noise vibration coupling, and in particular to a bidirectional broadband fluid-solid coupling simulation method for hypersonic turbulent vibration noise. Background Art

[0002] The flow field of fluid-induced solid wall vibration and wall vibration feedback is a key issue in the study of the coupling mechanism of flow noise and vibration inside and outside the aircraft. At present, the coupling of most commercial software is limited to the low-frequency motion part, that is, the fluid calculation software applies the resolvable steady and unsteady loads to the solid, and the solid applies the resolved low-frequency motion results to the flow field boundary. However, the real wall near-field mutual coupling makes the dynamic behavior of the bidirectional fluid-solid coupling of high-speed aircraft extremely complex, and revealing the bidirectional fluid-solid coupling mechanism of aircraft wall vibration and fluid flow is the premise for establishing a high-precision aeroelastic model of high-speed aircraft.

[0003] In conventional fluid-solid coupling research, the nonlinear NS equations in fluid mechanics are solved separately by computational fluid dynamics (CFD) to obtain the force applied to the computational structural dynamics (CSD) program, and then the nonlinear vibration problem in solid mechanics is solved by the finite element method to form a moving boundary, that is, the dynamic mesh technology reacts to the fluid. This method is relatively mature, but it can generally only handle medium and low frequency vibration coupling in the field of medium and low speed flow. There is currently no complete solution for the bidirectional coupled vibration simulation of the high frequency and ultra-high frequency parts of hypersonic turbulent noise.

[0004] The defects of the prior art are as follows:

[0005] 1) It is difficult to analyze broadband pressure pulsations under hypersonic flow conditions. Even with advanced large eddy simulation and direct numerical simulation, due to the limitations of grid scale and computational cost, only pressure dynamic loads in a limited frequency domain can be analyzed.

[0006] 2) The general finite element model has limited analytical capabilities for high-frequency vibrations, and it is difficult to perform time domain simulations over a wide frequency vibration range.

[0007] 3) Even if the solid domain resolves broadband vibrations, direct fluid-solid coupling cannot be performed due to the limited ability of the fluid domain to resolve high-frequency boundary vibrations. That is, the current bidirectional coupling model is incomplete. In general, hypersonic bidirectional fluid-solid coupling is currently limited to low-frequency coupling, and high-frequency and ultra-high-frequency coupling are missing. Summary of the invention

[0008] In order to solve the problems in the above-mentioned background technology, the present invention provides a bidirectional broadband fluid-solid coupling simulation method for hypersonic turbulent vibration noise. Based on the high-precision fluid finite volume program (FVM) and the solid smooth particle dynamics method (SPH), the interaction between the two physical fields of fluid and structure is simultaneously considered, and computational fluid dynamics and computational structural dynamics are combined to establish a fluid-solid bidirectional coupling vibration model considering the elastic vibration feedback of the wall surface; overcome the difficulties in the current bidirectional fluid-solid coupling broadband vibration noise simulation, realize the bidirectional broadband domain fluid-solid information interaction between fluid and solid, and provide a basis and guidance for the prediction and processing of broadband bidirectional fluid-solid coupling vibration noise in engineering practice.

[0009] To achieve the above object, the present invention provides a bidirectional broadband fluid-solid coupling simulation method for hypersonic turbulent vibration noise, comprising the following steps:

[0010] Step 1: In the blade cluster of fluid calculation, compressible RANS (Reynolds average) or DES (detached eddy simulation) simulation is performed on the fluid through a compressible flow CFD program to calculate the average pressure / friction or medium- and low-frequency unsteady pressure / friction of the fluid on the structure, thereby obtaining the average or medium- and low-frequency excitation of the fluid on the solid;

[0011] Step 2: further extract the average turbulent kinetic energy, turbulent dissipation rate or sub-grid turbulent kinetic energy of each fluid-solid boundary point obtained by fluid simulation, calculate the turbulence intensity and turbulence scale at the local point, and then simulate the 0-20kHz broadband pressure pulsation load through the UDSRFG method, and transfer the pulsation load to the solid boundary;

[0012] Step 3: In the blade cluster of solid calculation, the vibration of the solid shell is solved by the SPH algorithm, and the pressure load obtained by the fluid calculation is converted into the acceleration of the particle. It is combined with the particle acceleration obtained by the momentum equation to calculate the broadband motion or deformation of the solid model under the excitation of the fluid load.

[0013] Step 4: In the fluid one calculation time step interval Internal (solid calculation time step is ), the broadband vibration results of the solid shell are filtered by real-time filtering method to separate medium-, low- and high-frequency signals. The low-frequency vibration of the solid shell less than 1kHz directly acts on the fluid motion boundary, and the high-frequency or ultra-high-frequency vibration greater than 1kHz is converted into a turbulent energy source term by statistical energy analysis method and introduced into the fluid domain in the form of energy radiation for coupling. The magnitude of the coupling is attenuated inversely proportional to the normal distance to the wall (keeping the total radiation energy unchanged);

[0014] Step 5: The bidirectional transmission and communication of fluid excitation and solid excitation data information is realized through the bidirectional transmission algorithm of fluid and solid physical quantities, thereby completing the hypersonic broadband bidirectional fluid-solid coupling calculation.

[0015] Preferably, in step one, a fluid domain grid is drawn using a grid drawing tool, calculation parameters (free flow Mach number, Reynolds number, static temperature, wall temperature, etc.) are determined, a compressible RANS simulation of the fluid is performed using a compressible flow CFD program, and the average pressure / friction force of the fluid on the structure is calculated; a compressible RANS simulation of the fluid is performed using a compressible flow CFD program, and the medium and low frequency unsteady pressure / friction force of the fluid on the structure is calculated, and the calculated force is directly used as the average or medium and low frequency force load acting on the solid moving boundary.

[0016] Preferably, in step 2, after performing compressible RANS simulation calculation on the fluid, the average turbulent kinetic energy and turbulent dissipation rate of each fluid-solid boundary point obtained by fluid simulation are extracted; after performing compressible DES simulation calculation on the fluid, the sub-grid turbulent kinetic energy of each fluid-solid boundary point obtained by fluid simulation is extracted, and the formula is used. The turbulence intensity and turbulence scale at the local point are calculated;

[0017] in, represents the turbulence intensity, represents the turbulence integral scale; Indicates the average speed at the location; express The empirical constant of is 0.09 by default; represents the circular frequency; Represents the spatial wave number.

[0018] Preferably, in step 2, for a given three-dimensional energy spectrum , discretized into several single pieces The combination of is expressed as:

[0019] ;

[0020] in, represents the Dirichlet function; represents the characteristic wave number; The serial number indicating the number of energy spectrum slices;

[0021] For Sheet energy spectrum , the corresponding pulsation speed It is expressed as:

[0022] ;

[0023] The spectral frequency Normal distribution, express The coordinate value of the direction, To indicate a moment; , is a random number uniformly distributed between 0 and 1. A series representing a harmonic function; Represents the coefficient before the cosine function; Represents the coefficient before the sine function.

[0024] Preferably, the turbulence spectrum It is expressed by the von Karman spectral model as:

[0025] ;

[0026] in, represents the local average speed, represents the free stream velocity;

[0027] Calculate the temperature ripple according to the following formula :

[0028] ;

[0029] in, represents the specific heat ratio, represents the local Mach number, represents the average temperature, Indicates speed pulsation;

[0030] The density pulsation is calculated according to the following formula :

[0031] ;

[0032] in, Represents the average density; the average flow field here adopts the corresponding physical quantity obtained by RANS simulation;

[0033] Finally, the fluid pressure load is calculated by the following formula: :

[0034] ;

[0035] in, represents the universal gas constant.

[0036] Preferably, in step 3, for the load calculated by the fluid, the flow field load is converted into the acceleration of the solid using the relationship between pressure, force and acceleration:

[0037] ;

[0038] ;

[0039] in, is the pressure load of the flow field on the solid, is the contact area, is the force, is the solid mass, is the acceleration; in the SPH algorithm, it is discretized as:

[0040] ;

[0041] ;

[0042] ;

[0043] In the formula Indicates the solid particle number, , , Represents the flow field pressure conversion Acceleration of the particle exist x, y, z The components in three directions, is the flow field pressure on the particle, for The components of the particle's normal vector in the x, y, and z directions, is the particle mass, is the side length of the cubic region represented by the particle.

[0044] Preferably, according to the TLSPH completely Lagrangian smoothed particle dynamics method, the momentum equation for solid calculation is:

[0045] ;

[0046] in Represents particles and its neighborhood The first pk stress of the particle; represents the kernel function gradient in the initial situation; yes The initial volume of the particle; is the material density; is the gradient correction matrix; and It is the particle acceleration obtained from the momentum equation, denoted as , then the total acceleration of the particle , and then by the formula:

[0047] ;

[0048] ;

[0049] The broadband motion or deformation of the solid model under the excitation of the fluid load is obtained; represents the particle speed, represents the acceleration of the particle, represents the time step, represents the time interval of a time step, Represents the coordinates of the particle.

[0050] Therefore, the present invention adopts the above-mentioned bidirectional broadband fluid-solid coupling simulation method for hypersonic turbulent vibration noise, which has the following beneficial effects:

[0051] (1) The present invention innovatively combines computational fluid dynamics, turbulent broadband pressure pulsation generation method and smoothed particle dynamics algorithm to complete the bidirectional coupling solution of broadband fluid excitation and solid vibration; the coupling solution covers the medium, low and high frequency bands, making up for the shortcomings in the field of broadband coupling of hypersonic aircraft;

[0052] (2) The present invention takes into account the elastic vibration feedback of the wall surface, which can theoretically ensure that the numerical simulation results of the fluid-structure coupling vibration and noise effects of aircraft structures with relatively large elasticity are consistent with the actual situation;

[0053] (3) The present invention can not only realize unidirectional coupling from fluid to solid and from solid to fluid, but also realize bidirectional coupling between fluid and solid, taking into account both the fluid excitation effect and the broadband dynamic response of the solid structure.

[0054] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 A schematic diagram of a method according to an embodiment of the present invention;

[0056] Figure 2 A schematic diagram of the transmission of fluid excitation to a solid structure according to an embodiment of the present invention;

[0057] Figure 3 Schematic diagram of the transmission of vibration of a solid structure to a fluid according to an embodiment of the present invention;

[0058] Figure 4 Schematic diagram of the comparison between the pressure time series and spectrum of a certain point of the hypersonic flow generated by the method under the uncoupled condition of the embodiment of the present invention and the high-precision hypersonic flow simulation (the solid line represents the DES simulation result, and the dotted line represents the UDSRFG calculation result;

[0059] Figure 5This is a diagram showing acceleration results at a certain position of a hypersonic turbulent noise bidirectional coupled vibration simulation considering wall elastic vibration feedback of a certain aircraft in an embodiment of the present invention;

[0060] Figure 6 A turbulent kinetic energy diagram of a certain area of ​​a hypersonic turbulent noise bidirectional coupled vibration simulation considering wall elastic vibration feedback of a certain aircraft in an embodiment of the present invention;

[0061] Figure 7 A turbulence intensity cloud map of a certain area of ​​a hypersonic turbulent noise bidirectional coupled vibration simulation considering wall elastic vibration feedback for a certain aircraft in an embodiment of the present invention;

[0062] Figure 8 This is a cloud diagram of the difference in turbulent kinetic energy before and after coupling according to an embodiment of the present invention. DETAILED DESCRIPTION

[0063] In order to make the purpose, technical scheme and advantages disclosed in the embodiments of the present invention clearer, the embodiments of the present invention are further described in detail in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the embodiments of the present invention and are not intended to limit the embodiments of the present invention. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions.

[0064] It should be noted that the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or server that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units that are not explicitly listed or inherent to these processes, methods, products or devices.

[0065] Like reference numerals and letters denote similar items in the following drawings, and thus, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0066] In the description of the present invention, it should be noted that the terms "upper", "lower", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, or are directions or positional relationships in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0067] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "setting", "installation" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0068] Example

[0069] like Figure 1 As shown in the figure, a hypersonic turbulent vibration noise bidirectional broadband fluid-solid coupling simulation method described in the present invention mainly includes three parts: (1) calculating the fluid average force load, unsteady medium-low frequency and high-frequency pulsating pressure load by combining computational fluid dynamics (RANS, DES) with a turbulent broadband noise simulation algorithm (UDSRFG); (2) solving the heat conduction of the solid structure and the thermodynamic response and deformation under broadband loads by smooth particle dynamics (SPH); (3) realizing hypersonic broadband bidirectional fluid-solid coupling calculation by a bidirectional transfer algorithm of fluid and solid physical quantities.

[0070] Figure 2 and Figure 3 The transmission information and coupling method from fluid excitation to solid structure and the transmission information and coupling method from solid structure vibration to fluid are respectively given. According to these figures, the bidirectional coupled vibration simulation method of hypersonic turbulent noise considering wall elastic vibration feedback proposed in the present invention includes the following steps:

[0071] Step 1: Draw the fluid domain grid using the grid drawing tool, determine the calculation parameters (free flow Mach number, Reynolds number, static temperature, wall temperature, etc.), and in the blade cluster for fluid calculation, perform compressible RANS simulation of the fluid using the compressible flow CFD program to calculate the average pressure / friction of the fluid on the structure; perform compressible RANS simulation of the fluid using the compressible flow CFD program to calculate the medium and low frequency unsteady pressure / friction of the fluid on the structure, thereby obtaining the average or medium and low frequency excitation of the fluid on the solid. These forces will directly act as average or medium and low frequency force loads (<1kHz) acting on the moving boundary of the solid.

[0072] Step 2: further extract the average turbulent kinetic energy and turbulent dissipation rate of each fluid-solid boundary point obtained by fluid simulation. After performing compressible RANS or DES simulation calculations on the fluid, the turbulent kinetic energy and turbulent dissipation rate of each fluid-solid boundary point obtained by fluid simulation are extracted. Figure 5 The formula shown The turbulence intensity and turbulence scale at the local point are calculated.

[0073] in, represents the turbulence intensity, represents the turbulence integral scale; Indicates the average speed at the location; express The empirical constant of is 0.09 by default; represents the circular frequency; Represents the spatial wave number.

[0074] The UDSRFG method is then used to simulate and obtain high-frequency and ultra-high-frequency loads (1-20kHz), and the low, medium and high-frequency loads are transferred to the solid boundary.

[0075] Here, the principle and process of UDSRFG algorithm are briefly explained using RANS simulation as an example.

[0076] For any given three-dimensional energy spectrum , which can be discretized into many single pieces The combination of can be expressed as:

[0077] ;

[0078] in, represents the characteristic wave number; The serial number indicating the number of energy spectrum slices.

[0079] For the mth energy spectrum , the corresponding pulsation speed It can be expressed as

[0080] ;

[0081] The spectral frequency Normal distribution, represents the coordinate value in the j direction, and t represents a certain moment. , where a is a random number uniformly distributed between 0 and 1. A series representing a harmonic function; Represents the coefficient before the cosine function; Represents the coefficient before the sine function.

[0082] Turbulence Energy Spectrum Taking the von Karman spectrum model as an example, it can be expressed as:

[0083] ;

[0084] Where I represents the turbulence intensity, L represents the turbulence integral scale, and U represents the local average velocity. Represents the free stream velocity.

[0085] Calculate the temperature ripple according to the following formula :

[0086] ;

[0087] in, represents the specific heat ratio, Ma represents the local Mach number, represents the average temperature, Indicates speed pulsation.

[0088] The density pulsation is calculated according to the following formula :

[0089] ;

[0090] in, Represents the average density.

[0091] The average flow field quantities here (including average velocity, average temperature, average density, average pressure, etc.) are the corresponding physical quantities obtained by RANS simulation.

[0092] Finally, the fluid pressure load p is calculated by the following formula:

[0093] ;

[0094] Here, R represents the universal gas constant.

[0095] Step 3: In the blade cluster of solid computing, the vibration of the solid shell is solved by the SPH algorithm to obtain the broadband motion or deformation under the excitation of the fluid load. In the SPH method, the continuous solid is discretized into a collection of interacting particles, and the motion of the particles is used to reflect the deformation of the solid.

[0096] For the loads calculated for the fluid, the relationship between pressure, force and acceleration can be used to convert the flow field loads into solid acceleration:

[0097] ;

[0098] ;

[0099] Here is the pressure load of the flow field on the solid, is the contact area, is the force, is the solid mass, is the acceleration. In the SPH algorithm, it is discretized as:

[0100] ;

[0101] ;

[0102] ;

[0103] In the formula Indicates the solid particle number, , , Represents the flow field pressure conversion Acceleration of the particle exist x, y, z The components in three directions, is the flow field pressure on the particle, for The components of the particle's normal vector in the x, y, and z directions, is the particle mass, is the side length of the cubic region represented by the particle.

[0104] In addition, according to the TLSPH (completely Lagrangian smoothed particle dynamics) method, the momentum equation for solid calculations is:

[0105] ;

[0106] in Represents particles and its neighborhood The first pk stress of the particle (i.e. nominal stress); represents the kernel function gradient in the initial situation; yes The initial volume of the particle; is the material density; is the gradient correction matrix; and It is the particle acceleration obtained from the momentum equation and can be expressed as The total acceleration of the particle is . Then according to the formula:

[0107] ;

[0108] ;

[0109] The broadband motion or deformation of the solid model under the excitation of the fluid load can be obtained. represents the particle speed, represents the acceleration of the particle, represents the time step, Represents the time interval of a time step. Represents the coordinates of the particle.

[0110] Step 4: In the fluid one calculation time step interval Internal (solid calculation time step is Represented by), the broadband vibration results of the solid shell are filtered by real-time filtering method to separate medium-, low-frequency and high-frequency signals. The low-frequency vibration of the solid shell less than 1kHz directly acts on the fluid motion boundary, and the high-frequency or ultra-high-frequency vibration greater than 1kHz is converted into turbulent energy source terms by statistical energy analysis method and introduced into the fluid domain in the form of energy radiation for coupling. The size of the coupling is attenuated inversely proportional to the normal distance to the wall (keeping the total radiation energy unchanged).

[0111] Step 5: The bidirectional transmission and communication of fluid excitation and solid excitation data information is realized through the bidirectional transmission algorithm of fluid and solid physical quantities, thereby completing the hypersonic broadband bidirectional fluid-solid coupling calculation.

[0112] Compared with the prior art, the present invention uses computational fluid dynamics algorithms and smooth particle dynamics algorithms to independently calculate fluid excitation and broadband dynamic response of solid structures, respectively, and divides the frequency domain space into medium-low frequency and high-frequency ranges. It is believed that vibrations in the medium-low frequency range can be sensed by the moving boundary, and vibrations in the high-frequency range are presented through energy radiation, and fluid-solid bidirectional coupling calculations are realized by the transmission of fluid excitation to the solid and the conduction of the broadband dynamic response of the solid structure to the fluid. It can meet the requirements of bidirectional coupling vibration simulation of hypersonic turbulent noise considering the feedback of wall elastic vibration, and the algorithm program has high solution accuracy and calculation efficiency. Here is an example to illustrate the flight conditions of a certain aircraft with an incoming flow velocity, total temperature, and total pressure equal to 942m / s, 510K, and 2Mpa, respectively. Figure 4 The pressure time series and spectrum of a certain point in the hypersonic flow generated by this method under uncoupled conditions are compared with the high-precision hypersonic flow simulation. Figure 5 , Figure 6 , Figure 7 , Figure 8 The results of acceleration, turbulent kinetic energy and turbulence intensity at a certain position of a certain aircraft in a bidirectional coupled vibration simulation of hypersonic turbulent noise considering the feedback of wall elastic vibration are given respectively.

[0113] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A bidirectional broadband fluid-solid coupling simulation method for hypersonic turbulent vibration noise, characterized by: The following steps are involved: Step 1: In the blade cluster of fluid calculation, compressible RANS Reynolds average or DES detached eddy simulation is performed on the fluid through a compressible flow CFD program to calculate the average pressure / friction or medium- and low-frequency unsteady pressure / friction of the fluid on the structure, thereby obtaining the average or medium- and low-frequency excitation of the fluid on the solid; Step 2: further extract the average turbulent kinetic energy and turbulent dissipation rate of each fluid-solid boundary point obtained by fluid simulation, calculate the turbulence intensity and turbulence scale at the local point, and then simulate the 0-20kHz broadband pressure pulsation load through the UDSRFG method, and transfer the pulsation load to the solid boundary; Step 3: In the solid computing blade cluster, the vibration of the solid shell is solved by the solid SPH algorithm. The pressure load calculated by the fluid is converted into the acceleration of the particle. It is combined with the particle acceleration obtained by the momentum equation to calculate the broadband motion or deformation of the solid model under the excitation of the fluid load. Step 4: In the fluid one calculation time step interval The broadband results of solid shell vibration are filtered by real-time filtering method to separate medium- and low-frequency signals and high-frequency signals. The low-frequency vibration of the solid shell less than 1kHz directly acts on the fluid motion boundary. The high-frequency or ultra-high-frequency vibration greater than 1kHz is converted into turbulent energy source terms by statistical energy analysis method and introduced into the fluid domain in the form of energy radiation for coupling. The magnitude of the coupling decays inversely proportional to the normal distance to the wall. Step 5: The bidirectional transmission and communication of fluid excitation and solid excitation data information is realized through the bidirectional transmission algorithm of fluid and solid physical quantities, thereby completing the hypersonic broadband bidirectional fluid-solid coupling calculation.

2. The method for simulating bidirectional broadband fluid-solid coupling of hypersonic turbulent vibration noise according to claim 1 is characterized in that: In step one, the fluid domain grid is drawn using a grid drawing tool to determine the calculation parameters, which include the free flow Mach number, Reynolds number, static temperature, and wall temperature. The compressible RANS simulation of the fluid is performed using a compressible flow CFD program to calculate the average pressure / friction force of the fluid on the structure. The compressible RANS simulation of the fluid is performed using a compressible flow CFD program to calculate the medium and low frequency unsteady pressure / friction force of the fluid on the structure. The calculated force is directly used as the average or medium and low frequency force load acting on the solid moving boundary.

3. The method for simulating bidirectional broadband fluid-solid coupling of hypersonic turbulent vibration noise according to claim 2 is characterized in that: In step 2, after the compressible RANS simulation calculation of the fluid, the average turbulent kinetic energy and turbulent dissipation rate of each fluid-solid boundary point obtained by the fluid simulation are extracted. After the compressible DES simulation calculation of the fluid, the sub-grid turbulent kinetic energy of each fluid-solid boundary point obtained by the fluid simulation is extracted. The formula The turbulence intensity and turbulence scale at the local point are calculated; in, represents the turbulence intensity, represents the turbulence integral scale; Indicates the average speed at the location; express The empirical constant of is 0.09 by default; represents the circular frequency; Represents the spatial wave number.

4. The method for simulating bidirectional broadband fluid-solid coupling of hypersonic turbulent vibration noise according to claim 3 is characterized by: In step 2, for a given three-dimensional energy spectrum , discretized into several single pieces The combination of is expressed as: ； in, represents the Dirichlet function; represents the characteristic wave number; The serial number indicating the number of energy spectrum slices; For Sheet energy spectrum , the corresponding pulsation speed It is expressed as: ； The spectral frequency Normal distribution, express The coordinate value of the direction, Indicates a moment; , is a random number uniformly distributed between 0 and 1. A series representing a harmonic function; Represents the coefficient before the cosine function; Represents the coefficient before the sine function.

5. The method for simulating bidirectional broadband fluid-solid coupling of hypersonic turbulent vibration noise according to claim 4 is characterized in that: Turbulence Energy Spectrum It is expressed by the von Karman spectral model as: ； in, represents the local average speed, represents the free stream velocity; Calculate the temperature ripple according to the following formula : ； in, represents the specific heat ratio, represents the local Mach number, represents the average temperature, Indicates speed pulsation; The density pulsation is calculated according to the following formula : ； in, Represents the average density; the average flow field here adopts the corresponding physical quantity obtained by RANS simulation; Finally, the fluid pressure load is calculated by the following formula: : ； in, represents the universal gas constant.

6. The method for simulating bidirectional broadband fluid-solid coupling of hypersonic turbulent vibration noise according to claim 5 is characterized in that: In step 3, for the load calculated for the fluid, the relationship between pressure, force, and acceleration is used to convert the flow field load into the acceleration of the solid: ； ； in, is the pressure load of the flow field on the solid, is the contact area, is the force, is the solid mass, is the acceleration; in the SPH algorithm, it is discretized as: ； ； ； In the formula Indicates the solid particle number, , , Represents the flow field pressure conversion Acceleration of the particle exist x, y, z The components in three directions, is the flow field pressure on the particle, for The components of the particle's normal vector in the x, y, and z directions, is the particle mass, is the side length of the cubic region represented by the particle.

7. The method for simulating bidirectional broadband fluid-solid coupling of hypersonic turbulent vibration noise according to claim 6 is characterized by: According to the TLSPH completely Lagrangian smoothed particle dynamics method, the momentum equation for solid calculation is: ； in Represents particles and its neighborhood The first pk stress of the particle; represents the kernel function gradient in the initial situation; yes The initial volume of the particle; is the material density; is the gradient correction matrix; and It is the particle acceleration obtained from the momentum equation, denoted as , then the total acceleration of the particle , and then by the formula: ； ； The broadband motion or deformation of the solid model under the excitation of the fluid load is obtained; represents the particle speed, represents the acceleration of the particle, represents the time step, represents the time interval of a time step, Represents the coordinates of the particle.

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