A magnetic levitation propulsion dynamics calculation method, device, equipment and medium

Abstract

The application discloses a kind of magnetic suspension propulsion dynamics calculation method, device, equipment and medium, establish electromagnetic propulsion booster dynamics model and electromagnetic propulsion booster aerodynamic model, based on Fluent UDF establish real-time exchange database, so that electromagnetic propulsion booster dynamics model and electromagnetic propulsion booster aerodynamic model carry out data exchange, using electromagnetic propulsion booster dynamics model carries out dynamics calculation and obtains the displacement data of booster, displacement data is converted into the aerodynamic load of booster, based on the aerodynamic load of booster and preset electromagnetic force, boot rail acting force and structure parameter solve dynamics equation and obtain the displacement of next time step, in the case of all time steps are completed, generate the dynamic response curve of entire operation process, based on Fluent UDF database dynamic interaction and step-by-step start-stop control strategy, solved the defect that traditional interpolation method cannot reflect dynamic reaction, realized the synchronous accurate solution of aerodynamic load and structure response.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of load calculation, in particular to a maglev propulsion dynamics calculation method, device, equipment and medium. BACKGROUND

[0002] The speed of the booster continuously changes during operation and is accompanied by strong vibration, resulting in dynamic changes in the attitude of the booster. The changes in speed and attitude directly affect the aerodynamic load and electromagnetic load acting on the booster; conversely, these loads significantly affect the dynamic response characteristics of the booster. Especially under high-speed operation conditions, the mutual coupling effect between the dynamic response and the aerodynamic / electromagnetic load is more intense. Accurate calculation of the system dynamic response throughout the operation process is not only a key basis for guiding the design of each subsystem, but also a core prerequisite for ensuring the operation safety of the entire system.

[0003] At present, in the dynamics calculation of simulating the whole process dynamic response of the booster, the combined action of the aerodynamic load and the electromagnetic load is mainly considered. A commonly used implementation method in the industry is as follows: first, the aerodynamic load of the booster under different running speeds and different attitude angle combinations, and the electromagnetic load under different running speeds and different magnetic track spacing combinations are calculated in advance through theoretical calculation, wind tunnel test or numerical simulation. Then, the calculated aerodynamic load and electromagnetic load data are sorted into a multi-dimensional interpolation table. Finally, during the dynamics calculation, the aerodynamic load and electromagnetic load at the current time are obtained in real time through table lookup interpolation according to the current speed, attitude angle and magnetic track spacing and other state parameters, and are input as external excitation into the dynamics model.

[0004] Although the above load input method based on the preset interpolation table can simulate the dynamic response process to some extent, it has the following significant shortcomings: first, the coverage and adaptability of the interpolation points are limited, and the speed, attitude and other key state parameter points required for interpolation calculation are pre-selected discrete points. This selection method cannot comprehensively cover all possible operating conditions, especially when the speed changes sharply or the transient process in a specific speed interval is experienced, the interpolation points may not accurately capture the complex dynamic response characteristics in the interval. Second, the dynamic reaction of the load is ignored, the aerodynamic load is usually calculated by adopting the "steady" assumption in the existing method. This method completely ignores the dynamic reaction of the actual motion state of the booster on the surrounding flow field, that is, it cannot reflect the reaction of the dynamic response on the aerodynamic load. Therefore, there is an essential gap between the aerodynamic load input provided by the interpolation method and the real, non-steady aerodynamic load affected by the feedback of the dynamic response of the booster, resulting in a decrease in the accuracy of the dynamics calculation. This directly affects the evaluation accuracy of the reliability and operation safety of the system design. SUMMARY

[0005] The purpose of the present application is to overcome the existing technical defects, and provide a magnetic levitation propulsion dynamics calculation method, device, equipment and medium. Through the way of aerodynamic and dynamic coupling solution, the aerodynamic load changing in the running process is calculated in real time, so that the consideration of the aerodynamic load of the magnetic levitation electromagnetic propulsion booster in the running process is closer to the real situation, and the calculated aerodynamic load and dynamic response are more accurate.

[0006] The purpose of the present application is achieved by the following technical solutions:

[0007] In a first aspect, the present application provides a magnetic levitation propulsion dynamics calculation method, which comprises:

[0008] The electromagnetic propulsion booster dynamics model and the electromagnetic propulsion booster aerodynamic model are established respectively;

[0009] Based on the Fluent UDF, a real-time exchange database is established to enable the electromagnetic propulsion booster dynamics model and the electromagnetic propulsion booster aerodynamic model to exchange data;

[0010] The displacement data of the booster is obtained by using the electromagnetic propulsion booster dynamics model for dynamics calculation;

[0011] The displacement data is converted into the aerodynamic load of the booster by using the electromagnetic propulsion booster aerodynamic model;

[0012] The dynamics equation is solved based on the aerodynamic load of the booster, the preset electromagnetic force, the shoe rail acting force and the structure parameters by using the electromagnetic propulsion booster dynamics model to obtain the displacement of the next time step;

[0013] In the case where all time steps are completed, the dynamic response curve of the entire running process is generated.

[0014] In a possible implementation, the electromagnetic propulsion booster dynamics model is established by using multi-body dynamics software Simpack, and the establishment steps of the electromagnetic propulsion booster dynamics model comprise:

[0015] Based on the mass, the center of gravity coordinates and the rotational inertia around the main shaft of the booster, the reference points of all electromagnetic loads, aerodynamic loads and shoe rail loads are established in the space of the booster, and the spatial three-dimensional coordinate parameters of all reference points are given;

[0016] Force elements are created at each reference point, including aerodynamic force, electromagnetic force and shoe rail acting force. The electromagnetic force is applied by interpolation table, and the aerodynamic load is read by the displacement variable function to read the aerodynamic calculation result file.

[0017] In a possible implementation, the establishment steps of the electromagnetic propulsion booster aerodynamic model comprise:

[0018] The three-dimensional geometry model of the booster is imported into the fluid simulation software Fluent;

[0019] The external flow field calculation grid is established for the three-dimensional geometry model by using a grid pre-processing software;

[0020] A three-dimensional unsteady calculation method is adopted, and the turbulent flow model is set to be an SST k-omega model;

[0021] The calculation domain boundary is set to be a pressure outlet boundary, the track surface is set to be a non-slip wall surface, and the booster surface is set to be a moving wall surface,

[0022] The initial condition is set to be that the initial speed of the booster is equal to zero, and the motion of the booster in the flow field is simulated by using a coupling strategy of overlapping grids and dynamic grids.

[0023] In a possible implementation, the six-degree-of-freedom motion speed of the moving wall surface is determined by reading the displacement data output by the dynamic calculation in real time through a user-defined function.

[0024] In a possible implementation, the step of converting the displacement data into the aerodynamic load of the booster by using the electromagnetic propulsion booster aerodynamic model comprises:

[0025] In each time step, the displacement data is read from the real-time exchange database, and the displacement data comprises three-dimensional position coordinates of each reference point on the surface of the booster at the current time step and the previous time step;

[0026] The displacement difference of each reference point is calculated, and the moving speed of the surface of the booster is calculated;

[0027] The moving speed of the surface of the booster is set as a wall boundary condition of the booster by using the DEFINE_CG_MOTION module of the Fluent UDF;

[0028] The three-dimensional unsteady flow field iterative calculation is performed, the surface grid element is traversed by using the f_loop(f_all, thread) function, and the pressure center coordinates are extracted by combining the F_CENTROID(x, f_all, thread) function;

[0029] Based on the pressure distribution and the pressure center coordinates, the six-degree-of-freedom aerodynamic load vector is calculated by integration.

[0030] In a possible implementation, after the step of calculating the six-degree-of-freedom aerodynamic load vector, the step further comprises:

[0031] The aerodynamic load vector is written into a text file of the real-time exchange database, and the file content is updated in an overwrite manner.

[0032] In a possible implementation, the dynamic equation is: wherein , , are the mass, damping and stiffness of the booster system respectively, is the displacement of the system, is the velocity, is the acceleration, is the external force on the system.

[0033] In a second aspect, the application provides a magnetic levitation propulsion dynamics calculation device, which comprises:

[0034] A configuration module is configured to establish an electromagnetic propulsion booster dynamics model and an electromagnetic propulsion booster aerodynamic model respectively;

[0035] A data exchange module is configured to establish a real-time exchange database based on Fluent UDF, so that the electromagnetic propulsion booster dynamics model and the electromagnetic propulsion booster aerodynamic model exchange data;

[0036] A calculation module is configured to perform dynamics calculation using the electromagnetic propulsion booster dynamics model to obtain displacement data of the booster;

[0037] A conversion module is configured to convert the displacement data into aerodynamic load of the booster using the electromagnetic propulsion booster aerodynamic model;

[0038] A solving module is configured to solve a dynamics equation based on the aerodynamic load of the booster, a preset electromagnetic force, a shoe rail acting force and a structure parameter using the electromagnetic propulsion booster dynamics model to obtain displacement of the next time step;

[0039] A generation module is configured to generate a dynamic response curve of the entire running process when all time steps are completed.

[0040] In a third aspect, the application further provides a computer device, which comprises a processor and a memory, and the memory stores a computer program, which is loaded and executed by the processor to implement the magnetic levitation propulsion dynamics calculation method according to any one of the first aspect.

[0041] In a fourth aspect, the application further provides a computer readable storage medium, which stores a computer program, which is loaded and executed by a processor to implement the magnetic levitation propulsion dynamics calculation method according to any one of the first aspect.

[0042] The above main scheme and each further selected scheme of the application can be freely combined to form multiple schemes, which are all the schemes that can be used and claimed by the application; and the application can also be freely combined between each non-conflicting selection and between other selections. Those skilled in the art can understand that there are many combinations according to the prior art and common knowledge after understanding the schemes of the application, which are all the technical schemes claimed by the application, and are not listed here.

[0043] The application discloses a kind of magnetic levitation propulsion dynamics calculation method, device, equipment and medium, establish electromagnetic propulsion booster dynamics model and electromagnetic propulsion booster aerodynamic model, based on Fluent UDF Real-time exchange database is established, so that electromagnetic propulsion booster dynamics model and electromagnetic propulsion booster aerodynamic model carry out data exchange, using electromagnetic propulsion booster dynamics model carries out dynamics calculation and obtains the displacement data of booster, displacement data is converted into the aerodynamic load of booster, based on the aerodynamic load of booster and preset electromagnetic force, boot rail action force and structure parameter solving dynamics equation obtains the displacement of next time step, in the case where all time steps are completed, the dynamic response curve of entire running process is generated, based on Fluent UDF database dynamic interaction and step-by-step start-stop control strategy, the defect that traditional interpolation method cannot reflect dynamic reaction is solved, and the synchronous accurate solution of aerodynamic load and structure response is realized. BRIEF DESCRIPTION OF DRAWINGS

[0044] In order to more clearly illustrate the technical solutions of the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0045] Figure 1 A flowchart of a magnetic levitation propulsion dynamics calculation method proposed by an embodiment of the application is shown.

[0046] Figure 2 A coupling calculation flowchart proposed by an embodiment of the application is shown.

[0047] Figure 3 An interaction diagram of Fluent and Simpack software based on start-stop control law in coupling calculation proposed by an embodiment of the application is shown.

[0048] Figure 4 A curve diagram of aerodynamic drag variation of booster running throughout obtained by coupling calculation is shown.

[0049] Figure 5 A curve diagram of aerodynamic lift variation of booster running throughout obtained by coupling calculation is shown.

[0050] Figure 6 The aerodynamic pitching moment variation curve of the booster during the whole running is coupled and calculated.

[0051] Figure 7 The running speed of the booster over time is coupled and calculated, and a curve diagram is shown.

[0052] Figure 8 The vertical displacement of the center of the levitation magnet during the running of the booster is coupled and calculated, and a curve diagram of the variation over time is shown. DETAILED DESCRIPTION

[0053] The embodiments of the present application are described below through specific specific examples. The present application can also be implemented or applied through other different specific embodiments, and various modifications or changes can be made to the details in the specification without departing from the spirit of the present application. It should be noted that the following examples and features in the examples can be combined with each other without conflict.

[0054] Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the present application.

[0055] In the prior art, the interpolation calculation method can reflect the effect of the aerodynamic load on the dynamic response to some extent during the running process, but the selection of the interpolation speed point may ignore some dynamic response characteristics in the speed interval. In addition, the aerodynamic load in the interpolation calculation method is calculated by steady calculation, which cannot reflect the reaction of the dynamic response on the aerodynamic load. In summary, the existing interpolation calculation method has a gap between the consideration of the aerodynamic load and the actual situation.

[0056] In order to solve the problems in the prior art, the embodiments of the present application propose a magnetic suspension propulsion dynamics calculation method, device, equipment and medium, which can overcome the limitations of aerodynamic interpolation calculation method of aerodynamic load data, introduce the fluid-solid coupling idea into the magnetic suspension electromagnetic propulsion dynamics calculation, and calculate the changing aerodynamic load in the running process in real time through the aerodynamic and dynamic coupling solution method. The consideration of the aerodynamic load during the running of the magnetic suspension electromagnetic propulsion booster is closer to the actual situation, and the calculated aerodynamic load and dynamic response are more accurate. Next, it will be described in detail.

[0057] Please refer to Figure 1 , Figure 1 A flowchart of a magnetic suspension propulsion dynamics calculation method according to an embodiment of the present application is shown. The method comprises:

[0058] Step S1, respectively, establish electromagnetic propulsion booster dynamics model and electromagnetic propulsion booster aerodynamic model.

[0059] The establishment of aerodynamic model is completed by means of fluid simulation software Fluent, through importing the three-dimensional geometric model of booster, using grid pre-processing software to establish the outer flow field grid, and adopting the strategy of combining overlapping grid with dynamic grid, combining three-dimensional unsteady calculation method and SST k-ω turbulence model for aerodynamic calculation, while setting the corresponding boundary conditions and initial conditions to simulate the movement of booster in flow field.

[0060] The dynamics model of electromagnetic propulsion booster is established by using multi-body dynamics software Simpack, and the establishment steps of the dynamics model of electromagnetic propulsion booster include:

[0061] Based on the mass, center of gravity coordinates and moment of inertia around the main shaft of the booster, the reference points of all electromagnetic loads, aerodynamic loads and shoe rail loads are established on the space of the booster, and the spatial three-dimensional coordinate parameters of all reference points are given;

[0062] Force elements are created at each reference point, including aerodynamic force, electromagnetic force and shoe rail force. The electromagnetic force is applied by interpolation table, and the aerodynamic load is read by the displacement variable function to read the aerodynamic calculation result file.

[0063] Firstly, according to the basic parameters such as mass, center of gravity coordinates and moment of inertia around the main shaft of the booster, the initial dynamics model framework of the booster is constructed. Then, the action points of all electromagnetic loads, aerodynamic loads and shoe rail loads are determined on the spatial model of the booster, and the spatial three-dimensional coordinate parameters of these load reference points are given to ensure the accuracy of the load action position. Further, corresponding force elements are created at each load reference point, including aerodynamic force elements, electromagnetic force elements and shoe rail force elements.

[0064] Among them, the electromagnetic force is applied by interpolation table, and the size of the electromagnetic force is quickly and accurately obtained according to different working conditions and parameter conditions; while the aerodynamic load is dynamically read by the displacement variable function of Simpack, which generates the aerodynamic load result file by aerodynamic calculation software Fluent, realizes the real-time update and application of aerodynamic load in the dynamics model, and thus completes the establishment of the dynamics model of electromagnetic propulsion booster.

[0065] The establishment steps of electromagnetic propulsion booster aerodynamic model include:

[0066] Import the three-dimensional geometric model of booster by fluid simulation software Fluent;

[0067] Use grid pre-processing software to establish the outer flow field calculation grid for the three-dimensional geometric model;

[0068] The three-dimensional unsteady calculation method is adopted, and the turbulent flow model is set to SST k-omega model;

[0069] The pressure outlet boundary is set for the calculation domain boundary, the track surface is set as a non-slip wall, and the booster surface is set as a moving wall.

[0070] The initial condition is set as the initial speed of the booster equal to zero, and the coupling strategy of overlapping grid and dynamic grid is used to simulate the movement of the booster in the flow field.

[0071] Firstly, the three-dimensional geometric model of the booster is imported through the fluid simulation software Fluent, and the professional grid pre-processing software is used to generate high-quality grid required for external flow field calculation for the imported three-dimensional model. The quality of grid division directly affects the accuracy and efficiency of aerodynamic calculation. When setting the relevant parameters for aerodynamic calculation in Fluent, the three-dimensional unsteady calculation method is adopted to capture the time-varying characteristics of the flow field, so as to ensure that the calculation results can reflect the complex aerodynamic behavior of the booster in actual movement. At the same time, the SST k-omega model is selected as the turbulent flow model, which has high precision in dealing with near-wall flow and separation flow, and can effectively simulate the turbulent flow characteristics of the complex flow field around the booster.

[0072] For the setting of boundary conditions, the outlet boundary of the calculation domain is defined as a pressure outlet boundary to reasonably simulate the pressure environment when the fluid flows out of the calculation domain. The track surface is set as a non-slip wall, which meets the physical condition that the velocity of fluid on the solid surface is zero in actual flow. The booster surface is set as a moving wall, and its six-degree-of-freedom movement velocity is read by user-defined function (UDF) from the automatic mechanics calculation results, so as to realize the data interaction between the aerodynamic model and the dynamic model, and make the aerodynamic calculation dynamically adjust according to the actual movement state of the booster.

[0073] The initial condition is set as the speed of the dolly equal to zero, that is, the booster is initially in a static state. In order to effectively simulate the complex movement of the booster in the flow field, the coupling strategy of overlapping grid and dynamic grid is adopted. The overlapping grid technology can handle complex geometry and large-scale movement, while the dynamic grid technology is used to adapt to the shape change and position movement of the booster during movement, and the combination of the two ensures that the calculation grid can accurately follow the movement of the booster.

[0074] The six-degree-of-freedom movement velocity of the moving wall is determined by reading the displacement data output by the dynamic calculation in real time through the user-defined function.

[0075] The structural displacement data Δx is obtained by the data storage module, and then the speeds of each degree of freedom are calculated according to the formula v=Δx / Δt (the ratio of structural displacement and time step), and the speed data is applied to the boundary conditions of the booster wall surface. This real-time data exchange mode enables the aerodynamic model to dynamically adjust according to the dynamic calculation results, so as to more accurately simulate the complex motion state of the booster in actual operation.

[0076] Step S2, based on the Fluent UDF, a real-time exchange database is established to enable the electromagnetic propulsion booster dynamics model and the electromagnetic propulsion booster aerodynamic model to exchange data;

[0077] Based on the Fluent UDF, a real-time exchange database is established to ensure data exchange between the electromagnetic propulsion booster dynamics model and the aerodynamic model. This database stores the six-degree-of-freedom aerodynamic load and structural displacement of each component in the form of read-write text files, and is updated continuously during the calculation process.

[0078] Step S3, using the electromagnetic propulsion booster dynamics model to perform dynamics calculation to obtain the displacement data of the booster.

[0079] The displacement data of the booster is obtained by using the dynamics model for calculation, and then the data is stored in the real-time exchange database.

[0080] Step S4, using the electromagnetic propulsion booster aerodynamic model to convert the displacement data into the aerodynamic load of the booster.

[0081] The displacement data in the database is read by the aerodynamic model, and is converted into aerodynamic load. Specifically, the aerodynamic model reads the displacement data through the Fluent UDF, and converts the displacement into the speed boundary condition of the booster wall surface using the DEFINE_CG_MOTION module. Then, through the unsteady flow field iterative calculation, combined with the f_loop and F_CENTROID functions, the pressure center coordinates are extracted, and finally the six-degree-of-freedom aerodynamic load vector is obtained based on the pressure distribution integration, and the results are output to the database.

[0082] The step of using the electromagnetic propulsion booster aerodynamic model to convert the displacement data into the aerodynamic load of the booster includes:

[0083] In each time step, the displacement data is read from the real-time exchange database, and the displacement data includes the three-dimensional position coordinates of each reference point on the surface of the booster at the current time step and the previous time step;

[0084] The displacement difference of each reference point is calculated, and the moving speed of the booster surface is calculated;

[0085] The surface moving velocity of the booster is set as the wall boundary condition of the booster by the DEFINE_CG_MOTION module of Fluent UDF;

[0086] A three-dimensional unsteady flow field iterative calculation is performed, the f_loop(f_all, thread) function is used to traverse the surface grid element, and the F_CENTROID(x, f_all, thread) function is used to extract the pressure center coordinates;

[0087] Based on the pressure distribution and the pressure center coordinates, the six-degree-of-freedom aerodynamic load vector is calculated by integration.

[0088] In each time step, the displacement data is read from the real-time exchange database, the displacement data includes the three-dimensional position coordinates of each reference point on the surface of the booster at the current time step and the last time step. The displacement difference of each reference point is calculated, and the surface moving velocity of the booster is calculated according to the formula v=Δx / Δt, wherein Δx is the structure displacement data, and Δt is the time step. The calculated surface moving velocity of the booster is set as the wall boundary condition of the booster by the DEFINE_CG_MOTION module of Fluent UDF, so as to ensure that the aerodynamic calculation can accurately reflect the motion state of the booster.

[0089] Then, a three-dimensional unsteady flow field iterative calculation is performed. In this process, the f_loop(f_all, thread) function is used to traverse the grid elements on the surface of the booster, and the F_CENTROID(x, f_all, thread) function is used to extract the pressure center coordinates of each grid element. Based on the pressure distribution of the flow field and the extracted pressure center coordinates, the six-degree-of-freedom aerodynamic load vector is calculated by integration, including the aerodynamic drag, lift, side force, and moment around each axis. Finally, the calculated aerodynamic load results are output to the data storage module for reading and use by the Simpack dynamics calculation.

[0090] Step S5, using the electromagnetic propulsion booster dynamics model, based on the aerodynamic load of the booster and the preset electromagnetic force, the shoe rail acting force and the structure parameters, the dynamics equation is solved to obtain the displacement of the next time step.

[0091] The electromagnetic propulsion booster dynamics model is used for calculation to predict displacement at the next time step. Specifically, the Simpack software is started according to the control law to solve the system dynamics equation. The dynamics calculation is performed by reading the aerodynamic load vector in the real-time exchange database, combining the preset electromagnetic load interpolation table, the shoe rail acting force and the structure parameters (such as mass, damping, stiffness, etc.), and solving the dynamics equation by a numerical integration method, so as to calculate the six-degree-of-freedom displacement of the booster at the next time step. The calculated displacement data is then output to the real-time exchange database, and after the calculation of the time step is completed, the Simpack pauses the calculation and enters the waiting state until a start signal is received to start the calculation of the next time step.

[0092] The dynamics equation is: wherein , , are the mass, damping and stiffness of the booster system, is the displacement of the system, is the velocity, is the acceleration, is the external force acting on the system.

[0093] The dynamics calculation method of the high-speed magnetic suspension electromagnetic propulsion system based on aerodynamic-dynamics coupling simulation is established, the real-time coupling calculation of the aerodynamic load and the structure dynamic response is realized, and the accuracy and reliability of the high-speed magnetic suspension electromagnetic propulsion system dynamics simulation are significantly improved.

[0094] Step S6, in the case where all time steps are completed, the dynamic response curve of the entire operation process is generated.

[0095] Finally, through the post-processing function of the dynamics software, the displacement and other dynamic response parameters of each component are arranged into complete dynamic response curves, providing comprehensive data support for analyzing the dynamic performance of the booster.

[0096] In a possible implementation, in order to ensure the accuracy and reliability of the coupling calculation, the application adopts a multi-software coupling calculation method, and designs a step-by-step calculation start-stop control technology based on parameter identification:

[0097] Since the Simpack calculation will update the file constantly, only the calculation results of the last step are finally retained. Therefore, through the post-processing Scripting function of the Simpack, the six-degree-of-freedom displacement and other key dynamic response parameters of each component are output to the data storage module at the end of each time step. After the calculation is completed, these data are arranged to form complete dynamic response curves varying with time.

[0098] The whole calculation process is discretized into multiple smaller time steps, and a "first dynamics and then aerodynamics" calculation sequence is adopted. For the dynamics calculation module, there are active and inactive digital signal parameters. When the computer recognizes the active parameters, the Simpack solver starts and performs dynamic response solving; after the solving is completed, the parameter state is changed from active to inactive, and the dynamics calculation stops and enters the inactive state. The aerodynamic calculation module sets the sleep time between each time step through the Fluent user-defined function function. After the aerodynamic module completes the aerodynamic load solving, it enters the stop state, and the dynamics module performs dynamic load solving; when the aerodynamic calculation stop time reaches the sleep time, the aerodynamic module restarts and enters the calculation of the next time step.

[0099] In each time step, the aerodynamic calculation reads the six-degree-of-freedom displacement output by the dynamics calculation in the database, and takes the ratio of the time step length as the speed condition. After a certain number of internal iterations to reach the convergence criterion, the six-degree-of-freedom aerodynamic load of the booster is calculated, and the results are output to the database. Subsequently, the control law is set to suspend the aerodynamic calculation and wait for the start signal to enter the calculation of the next time step.

[0100] The steps after calculating the six-degree-of-freedom aerodynamic load vector also include:

[0101] The aerodynamic load vector is written into the text file of the real-time exchange database and the file content is updated in an overwrite manner.

[0102] After calculating the six-degree-of-freedom aerodynamic load vector, the result is written into the text file in the real-time exchange database, and the file content is updated in an overwrite manner. This operation ensures that the latest aerodynamic load vector obtained each time can be read by Simpack and used for subsequent dynamics calculation. Reading the aerodynamic load vector into the text file of the real-time exchange database requires outputting the aerodynamic load vector to the text file through the Fluent user-defined function. Then, the file content is updated in an overwrite manner, which involves the writing method of the file, and needs to ensure that the original file content is overwritten each time, rather than appended. At the same time, the format and content structure of the file also need to be considered to ensure that Simpack can correctly read it.

[0103] Figure 2 The coupling calculation flowchart proposed by the embodiment of the application is shown, which mainly realizes coupling calculation through real-time output and reading of the aerodynamic load solved by the aerodynamic simulation subsystem and the dynamic response solved by the structural dynamics simulation subsystem. The whole process is:

[0104] In the aerodynamics simulation subsystem, the background grid and component grid are first divided, and the overlapping interface and custom grid motion are set. Then, the unsteady N-S equation is solved, and the inner iteration is judged whether to meet the convergence criterion. If not, the iteration is continued; if yes, the aerodynamic load is output to the database. In the structural dynamics simulation subsystem, the system dynamics model receives the load input through the database, solves the multibody dynamics equation, and writes the output dynamics results into the database. The database serves as an intermediate medium to store and transfer the aerodynamic load and dynamics results, and realizes the data interaction between the two subsystems. Through this real-time output and reading mode, the aerodynamics simulation subsystem and the structural dynamics simulation subsystem cooperate with each other to form a closed-loop coupled simulation process.

[0105] Figure 3 An interaction schematic diagram of Fluent and Simpack software based on start-stop control law in coupling calculation proposed by the embodiments of the application is shown. Since the entire calculation process is discretized into multiple time steps, after the end of each time step, both software need to pause the calculation to perform data interaction.

[0106] Fluent is responsible for solving the N-S equation and outputting the aerodynamic force. After the end of each step calculation, Fluent enters a dormant state, waits for Simpack to complete the dynamics calculation, and the start-stop of Fluent is controlled by the set dormant time. During the dormant period, Fluent pauses the calculation so that Simpack reads the aerodynamic force data output by Fluent and performs dynamics calculation.

[0107] Simpack is responsible for solving the dynamics equation and outputting the dynamic response. After the end of each step calculation, Simpack pauses the calculation and waits for Fluent to update the aerodynamic force data. The start-stop of Simpack is controlled by parameter identification. When a specific parameter change (such as the start-stop control parameter changing from 0 to 1) is identified, Simpack starts or pauses the calculation.

[0108] In the coupling calculation process, the two software are synchronized through the start-stop control parameter. When Fluent completes the aerodynamic force calculation and outputs the results, the start-stop control parameter is set to 0→1, triggering Simpack to start dynamics calculation. After Simpack completes the dynamics calculation and outputs the dynamic response, the start-stop control parameter is set to 1→0, indicating Fluent to restart and perform the next step of aerodynamic force calculation.

[0109] The interaction mode based on the start-stop control law ensures that the calculations of the two softwares in each time step can be carried out in an orderly manner, and the necessary data interaction is carried out after the calculation is completed, so as to realize the efficient coupling between Fluent and Simpack.

[0110] Figure 4 A plot of the aerodynamic drag variation curve of the booster throughout the entire running process obtained by coupling calculation is shown, in which the horizontal axis represents time (in seconds) and the vertical axis represents aerodynamic drag (in Newtons). As can be seen from the figure, the aerodynamic drag gradually increases during the period from 0 to 4 seconds, and the overall trend presents a smooth curve.

[0111] Figure 5 A plot of the aerodynamic lift variation curve of the booster throughout the entire running process obtained by coupling calculation is shown, in which the upward vertical direction is defined as the positive direction. The horizontal axis represents time (in seconds) and the vertical axis represents aerodynamic lift (in Newtons). As can be seen from the figure, the aerodynamic lift presents a gradually increasing trend during the period from 0 to 4 seconds. The initial stage of the curve is relatively flat, and as time goes on, the aerodynamic lift gradually increases and reaches a high value near 4 seconds.

[0112] Figure 6 A plot of the aerodynamic pitch moment variation curve of the booster throughout the entire running process obtained by coupling calculation is shown, in which the direction that makes the booster lift its head is defined as the positive direction. The horizontal axis represents time (in seconds) and the vertical axis represents aerodynamic pitch moment (in Newton-meters). As can be seen from the figure, the aerodynamic pitch moment presents a gradually increasing trend during the period from 0 to 4 seconds. The initial stage of the curve is relatively flat, and as time goes on, the growth rate gradually increases, especially near 4 seconds, when the moment reaches a high value.

[0113] Figure 7 A plot of the variation curve of the running speed of the booster with time obtained by coupling calculation is shown. The horizontal axis represents time (in seconds) and the vertical axis represents the running speed of the booster (in meters per second). As can be seen from the figure, the speed of the booster presents a smooth and continuous rising trend during the period from 0 to 4 seconds. In the initial stage, the speed growth is relatively slow, and then the speed gradually increases, and finally a high running speed is reached near 4 seconds.

[0114] Figure 8A curve graph showing the vertical displacement of the center of the levitation magnet during the operation of the booster is coupled to calculate the time variation. The horizontal axis represents time (in seconds), and the vertical axis represents the vertical displacement (in meters). As can be seen from the graph, the vertical displacement of the levitation magnet shows obvious fluctuation within 0 to 4 seconds. In the initial stage, the displacement fluctuation amplitude is large, and then gradually decreases and tends to be stable. This shows that the levitation magnet is subjected to a larger vertical disturbance in the initial stage of the booster operation, but as time goes on, the system gradually reaches a balanced state, and the amplitude of the vertical displacement fluctuation decreases.

[0115] In summary, the present application takes into account the variation characteristics of the aerodynamic load in the dynamic calculation, can real-time solve the aerodynamic load and dynamic response of the booster in the whole operation process, and can analyze the complex dynamic response of the booster, and judge the suspension stability and operation safety.

[0116] Compared with the prior art, the embodiments of the present application have the following beneficial effects:

[0117] First, the accuracy of the input aerodynamic load in the dynamic simulation calculation of the electromagnetic propulsion system is effectively improved. By overcoming the limitations of the aerodynamic load data in the aerodynamic interpolation calculation method, the constantly changing aerodynamic load in the operation process is calculated in real time, so that the consideration of the aerodynamic load in the operation process of the magnetic levitation electromagnetic propulsion booster is closer to the actual situation.

[0118] Second, a real-time coupled calculation method for solving aerodynamics and dynamics is established, and the fluid-solid coupling idea is introduced into the magnetic levitation electromagnetic propulsion dynamics calculation. This innovative method breaks through the limitations of the traditional interpolation calculation method, and can more accurately simulate the actual operation of the electromagnetic propulsion booster.

[0119] A possible implementation of a magnetic levitation propulsion dynamics calculation device for performing each execution step and corresponding technical effect of the magnetic levitation propulsion dynamics calculation method shown in the above embodiments and possible implementations is given below. The device comprises:

[0120] A construction module is configured to establish a magnetic levitation electromagnetic propulsion dynamics model and a magnetic levitation electromagnetic propulsion aerodynamic model, respectively;

[0121] A data exchange module is configured to establish a real-time exchange database based on Fluent UDF, so that the magnetic levitation electromagnetic propulsion dynamics model and the magnetic levitation electromagnetic propulsion aerodynamic model exchange data;

[0122] A calculation module is configured to perform dynamics calculation using the magnetic levitation electromagnetic propulsion dynamics model to obtain displacement data of the booster;

[0123] A conversion module is configured to convert the displacement data into aerodynamic load of the booster using the magnetic levitation electromagnetic propulsion aerodynamic model.

[0124] a solving module configured to solve the dynamic equation based on the aerodynamic load of the booster, the preset electromagnetic force, the shoe rail acting force and the structure parameters to obtain the displacement of the next time step using an electromagnetic propulsion booster dynamic model;

[0125] a generating module configured to generate the dynamic response curve of the whole running process when all the time steps are completed.

[0126] The preferred embodiment provides a computer device which can implement the steps in any of the embodiments of the magnetic levitation propulsion dynamics calculation method provided in the embodiments of the application, and thus can implement the beneficial effects of the magnetic levitation propulsion dynamics calculation method provided in the embodiments of the application. Details are described in the foregoing embodiments, which will not be described here again.

[0127] Those skilled in the art can understand that all or part of the steps in the various methods of the above embodiments can be completed by instructions, or by relevant hardware controlled by the instructions. The instructions can be stored in a computer readable storage medium and loaded and executed by a processor. Therefore, the embodiments of the application provide a storage medium in which a plurality of instructions are stored. The instructions can be loaded by a processor to execute the steps in any of the embodiments of the magnetic levitation propulsion dynamics calculation method provided in the embodiments of the application.

[0128] The storage medium can include a read only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, etc.

[0129] Since the instructions stored in the storage medium can execute the steps in any of the magnetic levitation propulsion dynamics calculation method embodiments provided in the embodiments of the application, the beneficial effects that can be achieved by any of the magnetic levitation propulsion dynamics calculation methods provided in the embodiments of the application can be achieved. Details are described in the foregoing embodiments, which will not be described here again.

[0130] The above only describes the preferred embodiments of the application and is not used to limit the application. Any modification, equivalent replacement and improvement made within the spirit and principle of the application should be included in the protection scope of the application.

Claims

1. A method of calculating the dynamics of a magnetic levitation propulsion, characterized in that, The method comprises: Respectively establishing an electromagnetic propulsion booster dynamics model and an electromagnetic propulsion booster aerodynamic model; Based on the Fluent UDF, a real-time exchange database is established to enable data exchange between the electromagnetic propulsion booster dynamics model and the electromagnetic propulsion booster aerodynamic model; The electromagnetic propulsion booster dynamics model is used for dynamics calculation to obtain displacement data of the booster; The electromagnetic propulsion booster aerodynamic model is used to convert the displacement data into aerodynamic loads of the booster; the step of converting the displacement data into the aerodynamic loads of the booster using the electromagnetic propulsion booster aerodynamic model comprises: In each time step, the displacement data is read from the real-time exchange database, and the displacement data includes three-dimensional position coordinates of each reference point on the surface of the booster at the current time step and the previous time step; The displacement difference of each reference point is calculated, and the moving speed of the surface of the booster is calculated; The moving speed of the surface of the booster is set as a wall boundary condition of the booster through the DEFINE_CG_MOTION module of the Fluent UDF; A three-dimensional unsteady flow field iterative calculation is performed, the f_loop(f_all, thread) function is used to traverse the surface grid elements, and the F_CENTROID(x, f_all, thread) function is used to extract the pressure center coordinates; Based on the pressure distribution and the pressure center coordinates, a six-degree-of-freedom aerodynamic load vector is calculated by integration; The electromagnetic propulsion booster dynamics model is used to solve the dynamics equation based on the aerodynamic loads of the booster, preset electromagnetic forces, shoe rail acting forces and structure parameters to obtain the displacement of the next time step; When all the time steps are completed, a dynamic response curve of the entire running process is generated.

2. The magnetic levitation propulsion dynamics calculation method of claim 1, wherein, The electromagnetic propulsion booster dynamics model is established by using the multi-body dynamics software Simpack, and the establishment steps of the electromagnetic propulsion booster dynamics model comprise: Based on the mass, center of gravity coordinates and rotational inertia around the main shaft of the booster, reference points of all electromagnetic loads, aerodynamic loads and shoe rail loads are established on the space of the booster, and three-dimensional spatial coordinate parameters of all reference points are given; Force elements are created at each reference point, the force elements include aerodynamic forces, electromagnetic forces and shoe rail acting forces, the electromagnetic forces are applied through an interpolation table, and the aerodynamic loads are read from an aerodynamic calculation result file through a substitution variable function.

3. The magnetic levitation propulsion dynamics calculation method of claim 1, wherein, The establishment steps of the electromagnetic propulsion booster aerodynamic model comprise: The three-dimensional geometric model of the booster is imported through the fluid simulation software Fluent; The external flow field calculation grid is established for the three-dimensional geometric model by using a grid preprocessing software; A three-dimensional unsteady calculation method is adopted, and the turbulent flow model is set as the SST k-ω model; The calculation domain boundary is set as a pressure outlet boundary, the rail surface is set as a non-slip wall surface, and the surface of the booster is set as a moving wall surface, The initial condition is set as that the initial speed of the booster is equal to zero, and the motion of the booster in the flow field is simulated by using an overlapping grid and a dynamic grid coupling strategy.

4. The magnetic levitation propulsion dynamics calculation method of claim 3, wherein, The six-degree-of-freedom motion speed of the moving wall surface is determined by reading the displacement data output by the dynamics calculation in real time through a user-defined function.

5. The maglev propulsion dynamics calculation method of claim 1, wherein, After the step of calculating the six-degree-of-freedom aerodynamic load vector, the steps further comprise: The aerodynamic load vector is written into a text file of the real-time exchange database and the file content is updated in an overwrite manner.

6. The magnetic levitation propulsion dynamics calculation method of claim 1, wherein, The dynamic equation is: where , , m, c, k are the mass, damping and stiffness of the booster system, respectively, is the displacement of the system, is the velocity, is the acceleration, is the external force applied to the system.

7. A magnetic levitation propulsion dynamics calculation device characterized by comprising: The device comprises: A configuration module is configured to establish an electromagnetic propulsion booster dynamics model and an electromagnetic propulsion booster aerodynamic model respectively; A data exchange module is configured to establish a real-time exchange database based on a Fluent UDF, so that the electromagnetic propulsion booster dynamics model and the electromagnetic propulsion booster aerodynamic model exchange data; A calculation module is configured to perform dynamics calculation using the electromagnetic propulsion booster dynamics model to obtain displacement data of the booster; A conversion module is configured to read the displacement data from the real-time exchange database at each time step, the displacement data including three-dimensional position coordinates of each reference point on the surface of the booster at the current time step and the previous time step; The displacement difference of each reference point is calculated, and the moving speed of the surface of the booster is calculated; The moving speed of the surface of the booster is set as a booster wall boundary condition through a DEFINE_CG_MOTION module of the Fluent UDF; A three-dimensional unsteady flow field iterative calculation is performed, a f_loop(f_all, thread) function is used to traverse the surface grid element, and a F_CENTROID(x, f_all, thread) function is used to extract the pressure center coordinates; Based on the pressure distribution and the pressure center coordinates, a six-degree-of-freedom aerodynamic load vector is calculated by integration; A solving module is configured to use the electromagnetic propulsion booster dynamics model to solve the dynamics equation based on the aerodynamic load of the booster, a preset electromagnetic force, a shoe rail acting force and a structure parameter to obtain the displacement of the next time step; A generation module is configured to generate a dynamic response curve of the entire running process when all the time steps are completed.

8. A computer device, comprising: The computer device comprises a processor and a memory, and the memory stores a computer program, which is loaded and executed by the processor to implement the magnetic levitation propulsion dynamics calculation method according to any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, The storage medium stores a computer program, which is loaded and executed by the processor to implement the magnetic levitation propulsion dynamics calculation method according to any one of claims 1-6.

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