Method and system for constructing vehicle-induced fluctuating wind load calculation model of outer covering type sound barrier based on variable speed working condition and related device

Abstract

The invention provides a method and a system for constructing a vehicle-induced fluctuating wind load calculation model of an outer covering type sound barrier based on a variable speed working condition and a related device. The method comprises the following steps: step 1, constructing a transient flow field simulation model; 2, setting boundary conditions of the simulation model; step 3, constructing a simulation environment of a variable speed working condition of the simulation model; 4, setting parameters required by the simulation model during analogue simulation; step 5, constructing a monitoring point for monitoring the fluctuating wind load; step 6, completing construction of a vehicle-induced fluctuating wind load calculation model of the outer covering type sound barrier; according to the calculation model for the vehicle-induced fluctuating wind load of the outer covering type sound barrier, the calculation problem of the vehicle-induced fluctuating wind load on the surface of the outer covering type sound barrier under the working conditions of speed reduction and acceleration of a train can be solved, calculation errors such as negative grids and floating-point number anomalies can be effectively avoided, and the calculation efficiency and the result accuracy are improved.

Description

Technical Field

[0001] The present invention belongs to the field of externally covered sound barriers for high-speed railways, and relates to a method, system and related devices for constructing a calculation model of vehicle-induced pulsating wind load for externally covered sound barriers based on variable-speed conditions. Background Art

[0002] With the deepening of the concept of green environmental protection, noise pollution prevention and control has attracted much attention. As an important facility for railway noise control, sound barriers have been widely used in railway engineering construction. In recent years, the engineering applications of new structural forms of sound barriers such as vertical insertion plate type, semi / full enclosed type, integral type, and externally covered type have accumulated rich practical experience. Compared with traditional railway sound barriers, externally covered sound barriers have significant advantages in aspects such as bridge expansion joint treatment, acoustic effects, operation and maintenance, etc. However, in terms of wind uplift resistance, since the externally covered sound barrier is only fixed on the outside of the steel structure, its wind uplift resistance performance is relatively poor and it is greatly affected by vehicle-induced aerodynamic wind pressure. In addition, the application cases of externally covered sound barriers in high-speed railways are rare, the aerodynamic effects at high vehicle speeds are not clear, and the domestic current specifications do not give the design parameters of pulsating wind load for this type of sound barrier.

[0003] The main methods for obtaining vehicle-induced pulsating wind load on the surface of the sound barrier are dynamic model tests, wind tunnel tests, on-site measurements and numerical simulations. Compared with other methods, numerical simulation can simulate the hydrodynamic process under complex conditions at a lower cost and faster speed, and at the same time provide detailed and accurate data output. At present, the numerical simulations of pulsating wind load by domestic and foreign scholars are mostly obtained by constant vehicle speed and paving grid technology. This method cannot reflect the changes in pulsating wind load on the surface of the sound barrier during train deceleration and acceleration, and at the same time, negative grids and floating-point number anomalies are likely to occur under complex conditions, resulting in the interruption of calculations. Summary of the Invention

[0004] The purpose of the present invention is to provide a method, system and related devices for constructing a calculation model of vehicle-induced pulsating wind load for externally covered sound barriers based on variable-speed conditions, and solve the calculation problem of vehicle-induced pulsating wind load on the surface of externally covered sound barriers under train deceleration and acceleration conditions.

[0005] In order to achieve the above purpose, the technical solution adopted by the present invention is: The method for constructing a calculation model of vehicle-induced pulsating wind load for externally covered sound barriers based on variable-speed conditions provided by the present invention includes the following steps: Step 1, respectively construct a train model, an externally covered sound barrier model and a flow field domain; Step 2, respectively perform grid division on the train model, the externally covered sound barrier model and the flow field domain to obtain a train model grid, an externally covered sound barrier model grid and a flow field domain grid; Step 3: Construct a transient flow field simulation model using the train model grid, the external acoustic barrier model grid, and the flow field domain grid; Step 4: Set the boundary conditions of the simulation model; Step 5: Define the deceleration / acceleration, motion function, and velocity vector of a single train or multiple trains respectively, and construct the simulation environment for the variable speed condition of the simulation model; Step 6: Set the parameters required for the simulation model during simulation; Step 7: Construct monitoring points for monitoring pulsating wind loads; Step 8: Complete the construction of the calculation model for the train-induced pulsating wind load of the external acoustic barrier.

[0006] Preferably, in Step 1, the train model includes a car body model and a grid interface generated outside the car body model; The external acoustic barrier model includes a box girder bridge deck, on which a track slab is provided, and a steel frame is provided on the track slab, and a sound-absorbing panel is provided at the free end of the steel frame.

[0007] The flow field domain is generated outside the external acoustic barrier model.

[0008] Preferably, in Step 2, the train model is meshed to obtain the meshed train model. The specific method is as follows: Generate surface meshes for the train model, and the minimum and maximum mesh sizes of the surface meshes are both 1 m; Describe the geometric structure of the train model, and define the geometric structure of the train model as consisting of a fluid region without voids; Update the boundary of the train model; Add a boundary layer at the grid interface of the train model; Generate the train body mesh, and the maximum element length of the train body mesh is 1 m.

[0009] Preferably, in Step 5, define the deceleration / acceleration, motion function, and velocity vector of a single or multiple trains, and construct the simulation environment of the simulation model. The specific method is as follows: Set the acceleration and deceleration; Set the function for calculating the deceleration time, which is used to calculate the time required to decelerate from the initial speed to the target speed; Set the motion function for simulating the deceleration process; Set the input of the motion function for simulating the deceleration process, and the input includes the initial speed and the target speed; Set the constraint of the motion function for simulating the deceleration process, and the constraint includes that the speed of an object at any moment under the variable speed condition cannot be less than the target speed, the velocity vector, and the angular velocity remains zero.

[0010] Preferably, in step 4, the boundary conditions of the simulation model are set, and the specific method is as follows: Set the surfaces of the overlying sound barrier and the train in the simulation model as wall surfaces; Set the left and right boundaries of the flow field domain as outlets; Set the interface between the train grid and the flow field domain grid as an overlapping grid, and create an overlapping grid interface.

[0011] In a second aspect, the system for constructing a calculation model of vehicle-induced pulsating wind load for an overlying sound barrier based on variable speed conditions provided by the present invention includes: A simulation model construction unit for respectively constructing a train model, an overlying sound barrier model, and a flow field domain; respectively performing mesh division on the train model, the overlying sound barrier model, and the flow field domain to obtain a train model mesh, an overlying sound barrier model mesh, and a flow field domain mesh; and constructing a transient flow field simulation model using the train model mesh, the overlying sound barrier model mesh, and the flow field domain mesh; A boundary condition setting unit for setting the boundary conditions of the simulation model; A simulation environment construction unit for respectively defining the deceleration, acceleration, motion function, and velocity vector of a single train or multiple trains, and constructing a simulation environment for variable speed conditions of the simulation model; A wind load calculation model construction unit for setting the parameters required for the simulation model during simulation; constructing monitoring points for monitoring pulsating wind load; and completing the construction of the calculation model of vehicle-induced pulsating wind load for the overlying sound barrier.

[0012] In a third aspect, an electronic device provided by the present invention includes a processor and a memory, and a computer instruction is stored on the memory. When the computer instruction is executed by the processor, the electronic device executes the method described above.

[0013] In a fourth aspect, a computing device cluster provided by the present invention includes at least one computing device, and each computing device includes a processor and a memory; The processor of the at least one computing device is used to execute the instructions stored in the memory of the at least one computing device, so that the computing device cluster executes the method described above.

[0014] In a fourth aspect, a computer program product provided by the present invention includes computer-executable instructions, and when the computer-executable instructions are executed, the method described above is implemented.

[0015] In a fifth aspect, a computer-readable storage medium provided by the present invention stores computer-executable instructions, and when the computer-executable instructions are executed by a processor, the method described above is implemented.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: The method for constructing a calculation model of vehicle-induced pulsating wind load for an external covering sound barrier based on variable speed conditions provided by the present invention defines the deceleration / acceleration, motion function, and velocity vector of a single or multiple trains, realizes the simulation environment of deceleration and acceleration conditions in the simulation model, loads the simulation environment into a simulation model including a train model, an external covering sound barrier model, and a flow field domain, forms a calculation model of vehicle-induced pulsating wind load for the external covering sound barrier, and finally quantifies the pulsating wind load and its spatial distribution characteristics on the surface of the external covering sound barrier under deceleration and acceleration conditions of high-speed trains, providing theoretical support for the design and application of such sound barriers. At the same time, compared with conventional simulations, the obtained calculation model of vehicle-induced pulsating wind load for the external covering sound barrier can solve the calculation problem of vehicle-induced pulsating wind load on the surface of the external covering sound barrier under deceleration and acceleration conditions of trains, and can effectively avoid calculation errors such as negative meshes and floating-point number exceptions, improving the calculation efficiency and the accuracy of the results. Description of the Drawings

[0017] Figure 1 is the flowchart of the present invention; Figure 2 is a schematic diagram of the train model; Figure 3 is a schematic diagram of the flow field domain model; Figure 4 is a schematic diagram of the train mesh division; Figure 5 is a schematic diagram of the external covering sound barrier mesh division; Figure 6 is a schematic diagram of the flow field domain mesh division; Figure 7 is the flowchart of the custom function; Figure 8 is a schematic diagram of the spatial distribution of the pulsating wind load on the surface of the external covering sound barrier; Figure 9 is the monitoring result diagram of the pulsating wind load on the surface of the external covering sound barrier. Detailed Embodiments

[0018] In the following description, specific details such as specific system structures and technologies are presented for the purpose of illustration rather than limitation, so as to thoroughly understand the embodiments of the present application. However, those skilled in the art should clearly understand that the present application can also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid unnecessary details from interfering with the description of the present application.

[0019] It should be understood that, as used in the specification of this application and the appended claims, the term "comprising" indicates the presence of the described features, wholes, steps, operations, elements and / or components, but does not preclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or their combinations.

[0020] It should also be understood that the term "and / or" as used in the specification of this application and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0021] As used in the specification of this application and the appended claims, the term "if" may be interpreted, depending on the context, as "when", "once", "in response to determining", or "in response to detecting". Similarly, the phrases "if determined" or "if [the described condition or event] is detected" may be interpreted, depending on the context, as meaning "once determined", "in response to determining", "once [the described condition or event] is detected", or "in response to detecting [the described condition or event]".

[0022] In addition, in the description of the specification of this application and the appended claims, the terms "first", "second", "third", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0023] Reference to "one embodiment" or "some embodiments" etc. described in the specification of this application means that a specific feature, structure or characteristic described in connection with that embodiment is included in one or more embodiments of this application. Thus, statements such as "in one embodiment", "in some embodiments", "in other some embodiments", "in still other embodiments", etc. that appear in different places in this specification do not necessarily all refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in another way. The terms "comprising", "including", "having" and their variants all mean "including but not limited to", unless otherwise specifically emphasized in another way.

[0024] Embodiment 1 The method for constructing a calculation model of vehicle-induced pulsating wind load for an external covering sound barrier based on variable speed conditions provided in this embodiment includes the following steps: Step 1, respectively construct a train model, an external covering sound barrier model and a flow field domain, wherein: The train model includes a car body model and a grid interface generated outside the car body model.

[0025] The external covering sound barrier model includes a box girder bridge deck, on which a track slab is arranged, on which a steel frame is arranged, and on the outside of the steel frame, a sound absorption board is arranged.

[0026] Step 2: Mesh the train model, the external acoustic barrier model, and the flow field domain respectively to obtain the meshed train model, the external acoustic barrier model, and the flow field domain. Step 3: Construct a transient flow field simulation model using the meshed train model, the external acoustic barrier model, and the flow field domain. Step 4: Set the boundary conditions of the simulation model. Step 5: Define parameters such as the deceleration / acceleration, motion function, and velocity vector of one or multiple trains to construct the simulation environment of the simulation model. Step 7: Set the parameters required for the simulation model during simulation. Step 8: Construct monitoring points for monitoring the pulsating wind load and post-processing graphics such as stress nephograms, streamlines, and vectors. Step 9: Complete the construction of the calculation model for the pulsating wind load caused by the external acoustic barrier due to the train. Step 10: Set the number of time steps, time step size, and maximum number of iterations according to the actual movement time of the train, and calculate the pulsating wind load using the calculation model for the pulsating wind load caused by the external acoustic barrier due to the train.

[0027] Embodiment 2 The method for constructing a calculation model for the pulsating wind load caused by the external acoustic barrier due to the train based on variable speed conditions provided in this embodiment includes the following steps: Step 1: Establish a train model.

[0028] In this embodiment, an initial vehicle body model is established using tools such as pulling, combining, splitting, splicing, and merging surfaces in SpaceClaim software; the initial vehicle body model is the initial model of a three - car formation Fuxinghao vehicle body, and this vehicle body model has no structures such as bogies, train doors, and pantographs. Smooth the surface of the obtained initial vehicle body model to obtain a vehicle body model, so as to reduce the calculation complexity and improve the calculation accuracy. Generate a mesh interface on the outside of the vehicle body model using the shell command to obtain a train model. Name the obtained vehicle body model and the mesh interface in the group. Details of the train and the mesh interface are shown in the appendix Figure 2 .

[0029] Step 2: Establish an external acoustic barrier model and a flow field domain.

[0030] In this embodiment, an initial external acoustic barrier model is established using tools such as pulling, combining, splitting, splicing, and merging surfaces in SpaceClaim software. The initial external acoustic barrier model includes a box girder bridge deck, on which a track slab is provided, and a steel frame is provided on the track slab, and a sound - absorbing panel is provided outside the steel frame.

[0031] Smooth and simplify the surface of the obtained initial model of the external acoustic barrier to obtain the final model of the external acoustic barrier.

[0032] Use the shell command to generate a flow field domain outside the external acoustic barrier model, which will be used for subsequent hydrodynamic analysis.

[0033] Name the obtained external acoustic barrier model, flow field domain boundary, and flow field domain inlet and outlet in the group. For the size of the flow field domain, see the appendix Figure 3 .

[0034] In the SpaceClaim software, according to the actual parameters such as train type, external acoustic barrier structure, and line spacing, establish the train model and the external acoustic barrier model strictly in a 1:1 ratio.

[0035] Save them in the corresponding files in the scdoc file format according to the two types of train and flow field domain, ensuring that the model files contain all necessary dimension markings and construction details for subsequent mesh generation.

[0036] Step 3: Mesh generation of the train model.

[0037] In this embodiment, on the initial page of the Fluent Meshing software, select "Double Precision" and set the number of solvers; select the "Watertight Geometry" workflow; Import the geometric model, select the "CAD" format and the unit "meter" for the file format; First, import the train model into the Fluent Meshing software; no local dimensions need to be added to the train model; Generate surface meshes for the train model, and set the sizes of the smallest and largest meshes that make up the surface meshes to 1 m, ensuring that the mesh sizes at the mesh interfaces are the same, thereby reducing the occurrence of isolated meshes in the later stage, improving the calculation efficiency, and ensuring the convergence of the model.

[0038] Describe the geometric structure of the train model, and define that the geometric structure of the train model consists of a fluid region without voids. There is no need to change all fluid-fluid region interface types from "wall" to "internal", and there is no need to apply shared topology; Update the boundaries of the train model, define the surface of the train model and the mesh interfaces in Step 1 as walls; define the internal space of the train model as a solid region, and the internal space of the mesh interfaces as a fluid region; Add boundary layers, and add 10 boundary layers at the mesh interfaces to ensure that there are more than 5 boundary layers on the overlapping mesh interfaces in subsequent transient calculations; Generate a train body mesh with a maximum element length of 1m. If a warning is displayed due to complex curves, sharp faces, or distorted elements in the train model, change the mesh growth rate from 1.2 to 1.15; improve the body mesh and use the default settings. Finally, the meshed train model is exported and saved as a "mesh.h5" file. The train mesh division diagram is shown in Figure 4 .

[0039] Step 4: Mesh the external sound barrier model and flow field.

[0040] like Figure 5 、 Figure 6 As shown, the external sound barrier model and flow field are generated into a surface mesh, the minimum mesh size of which is 0.5m and the maximum mesh size is 1m; Describe the geometric structure of the outer sound barrier model and the flow field, and define the geometric structure of the outer sound barrier model and the flow field as consisting of a fluid region without gaps; Update the outer sound barrier model and the boundaries of the flow field. Define the outer sound barrier model and the boundaries of the flow field in step 2 as walls; define the inlet and outlet of the flow field as pressure outlets. Add boundary layers at the mesh interface between the external sound barrier model and the flow field; add more than 5 boundary layers at the mesh interface; Generate a train body mesh, and the maximum unit length of the train body mesh is 1m.

[0041] In Fluent Meshing software, it is necessary to ensure that the train grid size is the same as or a multiple of the flow field grid size, reduce the number of isolated grids in the subsequent overlapping grid interface, and ensure the stability and convergence of the calculation. For example, the train model in this embodiment is 1m, and the external sound barrier model and flow field are 0.5-2m. In addition, it is still necessary to ensure that the boundary layer on the overlapping grid interface is more than 5 layers. After adopting this method, the number of isolated grids is controlled at about 300, which can ensure the convergence of subsequent model calculations.

[0042] Step 5: Set the custom function for the speed change condition. The specific method is: Set acceleration and deceleration; Set the function to calculate the deceleration time, which is used to calculate the time required to decelerate from the initial speed to the target speed; Set the motion function to simulate the deceleration process; Set the input of the motion function used to simulate the deceleration process, which includes the initial speed and the target speed; Set the constraints of the motion function used to simulate the deceleration process. The constraints include that the velocity of the object at any moment under variable speed conditions cannot be less than the target velocity, and the velocity vector and angular velocity remain zero.

[0043] In this embodiment, write this custom function in Visual Studio. For the overall process, see Figure 7 ; Step 5.1, call the header file of the custom function (UDF) for the computational fluid dynamics simulation software: #include "udf.h"; Step 5. II, define global variables to represent acceleration and deceleration (m / s 2 ): #define ACCELERATION 0.5 / / For example, the acceleration is 0.5 m / s 2 #define DECELERATION -0.5 / / For example, the deceleration is -0.5 m / s 2 (The negative sign indicates deceleration) Step 5.3, define a function to calculate the deceleration time. According to the given initial velocity, final velocity, and deceleration, calculate the time t required for the object to decelerate from the initial velocity to the final velocity: Calculation formula: t = (v - u) / a; u is the initial velocity; v is the final velocity; a is the deceleration (should be negative) The code is as follows: double calculateTimeToDecelerate(double initialVelocity, double finalVelocity, double deceleration) {return (finalVelocity - initialVelocity) / deceleration;} Step 5.4, customize the motion function to simulate the deceleration process: Define the motion of the geometric body (user-defined name, time step, train linear velocity, train angular velocity, time, time increment) The code is as follows: DEFINE_CG_MOTION(train_deceleration, dt, vel, omega, time, dtime) Step 5.5, initial velocity (convert 250 km / h to m / s): The code is as follows: static double initialVelocity = 69.444444444; / / 250 km / h Step 5.6, target velocity (converting 120 km / h to m / s): The code is as follows: double finalVelocity = 33.333333333; / / 120 km / h Step 5.7, calculate the total time required for deceleration; static double totalDecelerationTime=calculateTimeToDecelerate (initialVelocity,finalVelocity, DECELERATION); where totalDecelerationTime is the total deceleration time; initialVelocity is the initial velocity; finalVelocity is the final velocity; DECELERATION is the deceleration.

[0044] Step 5.8, calculate the velocity at the current moment (if the deceleration process is not yet complete): Calculation formula: ; is the initial velocity; v is the final velocity; a is the acceleration (should be negative) The code is as follows: double currentVelocity;if (time<totalDecelerationTime){currentVelocity = initialVelocity + DECELERATION time; where currentVelocity is the velocity value at the current moment; time is the time elapsed so far; totalDecelerationTime is the total deceleration time calculated previously; initialVelocity is the initial velocity; DECELERATION is the deceleration.

[0045] Step 5.9, ensure that the velocity is not lower than the target velocity (due to precision issues in floating-point operations); The code is as follows: if (currentVelocity < finalVelocity) { currentVelocity = finalVelocity;} else { currentVelocity = finalVelocity;} Step 5.11, set the velocity vector. Assume the movement is only along the x-axis, i.e., V[0] = current velocity, and V[1], V[2] are 0. Here, 0, 1, 2 represent the X, Y, Z axes respectively.

[0046] The code is as follows: NV_S(vel, =, 0.0); vel[0] = currentVelocity; vel[1] = 0; vel[2] = 0; Step 5.12, keep the angular velocity zero. Assume the train does not rotate, i.e., omega = 0.

[0047] The code is as follows: NV_S(omega, =, 0.0);} Step 5.13, complete the writing of the custom function and save it as a "cpp" file in the corresponding folder.

[0048] Note that the above code is a custom function for decelerating the speed from 250 km / h to 120 km / h. If it is an acceleration condition, assign a positive acceleration value to #define ACCELERATION, and correctly set the initial speed and target speed. In addition, the above function needs to be called multiple times in a loop or time-stepping framework to simulate the continuous deceleration process.

[0049] Step 6, use the meshed train model, external acoustic barrier model, and flow field domain to construct a simulation model, and combine the two-equation turbulence model based on the RANS method and the standard wall function to obtain the formula for calculating the vehicle-induced pulsating wind load on the surface of the external acoustic barrier corresponding to this simulation model.

[0050] In this embodiment, construct the simulation model in the Fluent Solution software. The specific method is: Set the number of solvers according to the performance of your own computer; Import the flow field domain grid, attach the train model grid, click to display the grid, and select transient time calculation. Since the present calculation model involves turbulent flow, the Realizable k-epsilon two-equation turbulence model (RKE) is an improved k-epsilon turbulence model. Compared with the standard k-epsilon model, it improves the eddy viscosity hypothesis of turbulence and can more reasonably describe the anisotropy of turbulence, showing better performance in dealing with complex flows, such as flows with separation, reattachment, etc. There are complex flow characteristics such as flow separation and vortex shedding in the flow field around the sound barrier under the action of vehicle-induced pulsating wind load. These characteristics of the RKE model enable it to capture some key information of such flows. Therefore, the Realizable k-epsilon two-equation turbulence model (RKE) based on the RANS method is selected, and the standard wall function (SWF) is used to calculate the vehicle-induced pulsating wind load on the surface of the overlying sound barrier:

[0051]

[0052] In the formula, is the air density; is the kinetic energy of the flow; is the time, used to describe the change process of turbulence over time; and are the velocity components of the flow field around the train in the i, j direction, i, j represents the x, y, z direction in the Cartesian coordinate system; μ is the air viscosity coefficient, a physical quantity describing the interaction between fluid molecules; is the turbulent dissipation rate; are the three components of the coordinate; is the turbulent viscosity coefficient, a physical quantity describing the viscous effect of the fluid in turbulent flow; and respectively represent the Prandtl numbers of the turbulent kinetic energy and the turbulent dissipation rate , used to describe the diffusion rates of momentum and heat in the turbulent transport process, ; represents the generation term of the turbulent kinetic energy generated by the mean velocity gradient; is the Reynolds stress tensor, describing the stress caused by turbulent pulsation; is the mean strain rate tensor, reflecting the deformation rate of fluid micro-elements; is the mean rotation rate tensor, describing the rotation characteristics of fluid micro-elements; is an empirical constant, used to adjust the model to adapt to different turbulent flows; , is a constant in the model; is an angular parameter related to the invariant of the strain rate tensor; is a dimensionless parameter, related to the strain rate and the turbulent dissipation rate.

[0053] Step 7, set the boundary conditions of the simulation model.

[0054] Set the surface of the external acoustic barrier and the train surface in the simulation model as walls; Set the left and right boundaries of the flow field domain as outlets; Set the interface between the train grid and the flow field domain grid as an overlapping grid, and create an overlapping grid interface.

[0055] Step 8, set the acceleration and deceleration conditions of the train.

[0056] Compile and load the custom UDF function obtained in Step 5 into the calculation model; Under the dynamic mesh menu, check the dynamic mesh, create / edit the dynamic mesh region, select the rigid body type, select the previously defined train grid name for the motion UDF function, and click the create command.

[0057] At this time, click to display the region motion and preview whether the train motion is correct. If it is incorrect, you need to return to check the UDF function.

[0058] Step 9, solution settings.

[0059] Select the semi-implicit pressure coupling algorithm for pressure-velocity coupling, select the distance-based Rhie-Chow interpolation for the flux type, use the cell-based least squares gradient for the gradient, select the standard pressure for the pressure, and select the first-order upwind scheme for momentum, turbulent kinetic energy, and turbulent dissipation rate.

[0060] Step 10, post-processing settings.

[0061] Before post-processing settings, the simulation model needs to be initialized.

[0062] Create monitoring points at the positions where the pulsating wind load needs to be monitored, where: Create a surface report and a node maximum value under the solution menu; Define the name, select "vertex maximum value" for the report type, and select "pressure" for the field variable; Select the created monitoring points and click OK to complete the monitoring of the pulsating wind load on the surface of the external acoustic barrier.

[0063] In addition, create post-processing graphics such as stress nephograms, streamlines, and vectors according to requirements.

[0064] After step 11 is completed, save the model file in the corresponding folder in the format of "Case&Data" for subsequent parametric expansion analysis.

[0065] Set the calculation parameters. In this step, according to the actual movement time of the train, set the number of time steps, time step size, and maximum number of iterations; finally, click to start the calculation.

[0066] After the calculation is completed, view the results. The monitoring and spatial distribution of the pulsating wind load on the external acoustic barrier are shown in Figure 8 、 Figure 9 。

[0067] Embodiment 2 This embodiment provides a system for constructing a calculation model of the vehicle-induced pulsating wind load on an external acoustic barrier based on variable-speed conditions, which is characterized by including: A simulation model construction unit for respectively constructing a train model, an external acoustic barrier model, and a flow field domain; respectively performing mesh division on the train model, the external acoustic barrier model, and the flow field domain to obtain a train model mesh, an external acoustic barrier model mesh, and a flow field domain mesh; constructing a transient flow field simulation model using the train model mesh, the external acoustic barrier model mesh, and the flow field domain mesh; A boundary condition setting unit for setting the boundary conditions of the simulation model; A simulation environment construction unit for respectively defining the deceleration, acceleration, motion function, and velocity vector of a single train or multiple trains, and constructing a simulation environment with variable-speed conditions for the simulation model; A wind load calculation model construction unit for setting the parameters required for the simulation model during simulation; constructing monitoring points for monitoring the pulsating wind load; and completing the construction of the calculation model of the vehicle-induced pulsating wind load on the external acoustic barrier.

[0068] Embodiment 3 This embodiment also provides a computing device. The computing device includes: a bus, a processor, a memory, and a communication interface. The processor, the memory, and the communication interface communicate through the bus. The computing device can be a server or a terminal device. It should be understood that the present application does not limit the number of processors and memories in the computing device.

[0069] The bus can be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For the sake of convenience of representation, the bus can include a path for transmitting information between various components of the computing device (for example, the memory, the processor, the communication interface).

[0070] The processor may include any one or more of processors such as a central processing unit (CPU), a graphics processing unit (GPU), a Tensor Processing Unit (TPU), an Application Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA), a microprocessor (MP), or a digital signal processor (DSP).

[0071] The memory may include a volatile memory, such as a random access memory (RAM). The processor may also include a non-volatile memory, such as a read-only memory (ROM), a flash memory, a hard disk drive (HDD), or a solid state drive (SSD).

[0072] The memory stores executable program codes, and the processor executes the executable program codes to respectively implement the functions of the foregoing first generation module, second generation module, and adjustment module, so as to implement, for example methods and the like. That is, the memory may store instructions for the methods and functions related to the computing device in any of the foregoing embodiments.

[0073] The communication interface uses a transceiver module such as, but not limited to, a network interface card or a transceiver to implement communication between the computing device and other devices or a communication network.

[0074] Embodiment 4 This embodiment further provides a computing device cluster. The computing device cluster includes at least one computing device. The computing device may be a server, such as a central server, an edge server, or a local server in a local data center. In some embodiments, the computing device may also be a terminal device such as a desktop computer, a laptop computer, or a smart phone.

[0075] The computing device cluster includes at least one computing device. Instructions for executing the methods and functions related to the computing device in any of the foregoing embodiments may be stored in the memories of one or more computing devices in the computing device cluster.

[0076] In some possible implementations, parts of the instructions for executing the methods and functions of the computing device involved in any of the above embodiments may also be stored separately in the memories of one or more computing devices in the computing device cluster. In other words, a combination of one or more computing devices may jointly execute the instructions for executing the methods and functions of the computing device.

[0077] It should be noted that the memories in different computing devices in the computing device cluster may store different instructions for respectively executing partial functions of the device.

[0078] In some possible implementations, one or more computing devices in the computing device cluster may be connected via a network. Among them, the network may be a wide area network or a local area network, etc. Two computing devices are connected via the network. Specifically, they are connected to the network through the communication interfaces in each computing device.

[0079] The embodiments of the present disclosure also provide a computer program product containing instructions, which, when running on a computer, cause the computer to execute the methods and functions of the computing device involved in any of the above embodiments.

[0080] Embodiment 5 This embodiment also provides a computer-readable storage medium, on which computer instructions are stored. When the processor runs the instructions, the processor is caused to execute the methods and functions of the computing device involved in any of the above embodiments.

[0081] Generally, the various embodiments of the present disclosure may be implemented in hardware or special circuits, software, logic, or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software, which may be executed by a controller, a microprocessor, or other computing devices. Although the various aspects of the embodiments of the present disclosure are shown and described as block diagrams, flowcharts, or using some other graphical representation, it should be understood that the blocks, devices, systems, technologies, or methods described herein may be implemented as, by way of non-limiting example, hardware, software, firmware, special circuits or logic, general hardware or a controller or other computing devices, or some combination thereof.

[0082] Embodiment 6 This embodiment provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product includes computer-executable instructions, such as instructions included in program modules, which are executed in a device on a target real or virtual processor to perform the processes / methods as referenced above with respect to the accompanying drawings. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, etc. that perform specific tasks or implement specific abstract data types. In various embodiments, the functions of program modules can be combined or divided as needed among the program modules. The machine-executable instructions for the program modules can be executed within a local or distributed device. In a distributed device, the program modules can be located in local and remote storage media.

[0083] The computer program code for implementing the methods of the present disclosure can be written in one or more programming languages. This computer program code can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus, such that when the program code is executed by the computer or other programmable data processing apparatus, the functions / operations specified in the flowcharts and / or block diagrams are implemented. The program code can be executed entirely on the computer, partially on the computer, as a stand-alone software package, partially on the computer and partially on a remote computer, or entirely on a remote computer or server.

[0084] In the context of the present disclosure, the computer program code or related data can be carried by any suitable carrier so that a device, apparatus, or processor can perform the various processes and operations described above. Examples of carriers include signals, computer-readable media, and the like. Examples of signals can include electrical, optical, radio, acoustic, or other forms of propagated signals, such as carrier waves, infrared signals, etc.

[0085] A computer-readable medium can be any tangible medium that contains or stores a program for or related to an instruction execution system, apparatus, or device, or a data storage device such as a data center that contains one or more available media. A computer-readable medium can be a computer-readable signal medium or a computer-readable storage medium. A computer-readable medium can include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatuses, or devices, or any suitable combination thereof. More detailed examples of computer-readable storage media include electrical connections with one or more wires, portable computer disks, hard disks, random access memories (RAMs), read-only memories (ROMs), erasable programmable read-only memories (EPROMs or flash memories), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0086] The above-described embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included within the protection scope of the present application.

Claims

1. A method for constructing a calculation model of vehicle-induced pulsating wind load for an outer-covered noise barrier based on variable speed conditions, characterized in that, It includes the following steps: Step 1: Build a train model, an external acoustic barrier model, and a flow field domain respectively; Step 2: Mesh the train model, the external acoustic barrier model, and the flow field domain respectively to obtain a train model mesh, an external acoustic barrier model mesh, and a flow field domain mesh; Step 3: Use the train model mesh, the external acoustic barrier model mesh, and the flow field domain mesh to build a transient flow field simulation model; Step 4: Set the boundary conditions of the simulation model; Step 5: Define the deceleration and acceleration, motion function, and velocity vector of a single train or multiple trains respectively to build a simulation environment for the variable speed condition of the simulation model; Step 6: Set the parameters required for the simulation model during simulation; Step 7: Build monitoring points for monitoring pulsating wind loads; Step 8: Complete the construction of the calculation model for the vehicle-induced pulsating wind load of the external acoustic barrier.

2. The method for constructing a calculation model of vehicle-induced pulsating wind load for an external acoustic barrier based on variable speed conditions according to claim 1, wherein In Step 1, the train model includes a car body model and a mesh interface generated outside the car body model; The external acoustic barrier model includes a box girder bridge deck, on which a track slab is arranged, and on the track slab, a steel frame is arranged, and a sound-absorbing board is arranged at the free end of the steel frame. The flow field domain is generated outside the external acoustic barrier model.

3. The method for constructing a calculation model of the pulsating wind load induced by an external acoustic barrier vehicle based on variable speed conditions according to claim 1, wherein In Step 2, when meshing the train model to obtain the meshed train model, the specific method is: Generate a surface mesh for the train model, and the minimum and maximum mesh sizes of the surface mesh are both 1 m; Describe the geometric structure of the train model and define that the geometric structure of the train model consists of a fluid region without voids; Update the boundary of the train model; Add a boundary layer at the mesh interface of the train model; Generate a train body mesh, and the maximum element length of the train body mesh is 1 m.

4. The method for constructing a calculation model of vehicle-induced pulsating wind load for an external acoustic barrier based on variable speed conditions according to claim 1, characterized in that In Step 5, when defining the deceleration and acceleration, motion function, and velocity vector of a single or multiple trains to build a simulation environment for the simulation model, the specific method is: Set the acceleration and deceleration; Set a function for calculating the deceleration time, which is used to calculate the time required to decelerate from the initial velocity to the target velocity; Set a motion function for simulating the deceleration process; Set the input of the motion function for simulating the deceleration process, and the input includes the initial velocity and the target velocity; Set the constraints of the motion function for simulating the deceleration process, and the constraints include that the velocity of an object at any moment under the variable speed condition cannot be less than the target velocity, the velocity vector, and the angular velocity remains zero.

5. The method for constructing a calculation model of vehicle-induced pulsating wind load for an external acoustic barrier based on variable speed conditions according to claim 1, characterized in that, In Step 4, when setting the boundary conditions of the simulation model, the specific method is: Set the surfaces of the external acoustic barrier and the train in the simulation model as wall surfaces; Set the left and right boundaries of the flow field domain as outlets; Set the interface between the train mesh and the flow field domain mesh as an overlapping mesh and create an overlapping mesh interface.

6. A system for constructing a calculation model of vehicle-induced pulsating wind load for an outer covering type sound barrier under variable speed conditions, characterized in that, It includes: A simulation model construction unit for building a train model, an external acoustic barrier model, and a flow field domain respectively; Mesh the train model, the external acoustic barrier model, and the flow field domain respectively to obtain a train model mesh, an external acoustic barrier model mesh, and a flow field domain mesh; use the train model mesh, the external acoustic barrier model mesh, and the flow field domain mesh to build a transient flow field simulation model; A boundary condition setting unit for setting the boundary conditions of the simulation model; A simulation environment construction unit is used to respectively define the deceleration, acceleration, motion function and velocity vector of a single train or multiple trains, and construct a simulation environment for the variable speed working conditions of the simulation model; A wind load calculation model construction unit is used to set the parameters required for the simulation model during simulation; construct monitoring points for monitoring pulsating wind loads; and complete the construction of the calculation model for the vehicle-induced pulsating wind load of the external acoustic barrier.

7. An electronic device, characterized in that, It includes a processor and a memory, and computer instructions are stored on the memory. When the computer instructions are executed by the processor, the electronic device executes the method according to any one of claims 1 to 5.

8. A cluster of computing devices, characterized in that, It includes at least one computing device, and each computing device includes a processor and a memory; The processor of the at least one computing device is used to execute the instructions stored in the memory of the at least one computing device, so that the computing device cluster executes the method according to any one of claims 1 to 5.

9. A computer program product, characterized in that, The computer program product contains computer-executable instructions, and the computer-executable instructions, when executed, implement the method according to any one of claims 1 to 5.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions, when executed by the processor, implement the method according to any one of claims 1 to 5.

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