Liquid rocket shaker parameter acquisition and anti-shake design method based on simulation data

Abstract

The application relates to a liquid rocket swing parameter acquisition and anti-swing design method based on simulation data, which comprises the following steps: anti-swing plate design, initial swing parameter calculation according to initial trajectory parameters, determination of an anti-swing design scheme meeting design requirements; swing simulation, batch simulation calculation of swing parameters, and arrangement to form data one by one; swing parameter processing, curve acquisition according to simulation calculation, and data fitting identification of key parameters in combination with a model; database establishment, swing parameter database establishment according to the acquired data; database use, extraction of coefficients and information as required, finding of corresponding swing parameter data in the database, and acquisition. The liquid rocket swing parameter acquisition and anti-swing design method based on simulation data can not only absorb the adaptability of simulation to various anti-swing design data acquisition corresponding to different states, but also can quickly realize swing parameter acquisition in the later iteration, so that the iteration efficiency is improved, and the time cost is saved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of liquid rocket anti-slosh design, and particularly relates to a liquid rocket sloshing parameter acquisition and anti-slosh design method based on simulation data. BACKGROUND

[0002] Liquid propellant in the liquid rocket tank will slosh during flight, affecting the rocket flight. In order to consider the influence of liquid sloshing in the rocket control system, the rules of sloshing are summarized into several key parameters, which are provided to the control professional for control system design and analysis. Then, in order to suppress the additional effects of sloshing and reduce the impact on rocket flight, an anti-slosh plate is generally provided in the tank structure, which increases the difficulty of acquiring sloshing parameters. With different requirements for sloshing suppression, anti-slosh designs are also diverse, which further increases the difficulty of acquiring sloshing parameters.

[0003] There are three ways to acquire sloshing parameters, namely test, empirical formula and simulation, each with advantages and disadvantages. Empirical formula and simulation are the main technical approaches to acquire sloshing parameters in the early stage of design, and test is the main approach to verify the design parameters after the preliminary design is completed. Empirical formula can only be used to calculate parameters under several common anti-slosh designs. Simulation is an effective method that can accurately acquire sloshing parameters at present. CN113553661B "Method for acquiring rocket propellant sloshing parameters and computer readable storage medium" discloses a method for acquiring rocket propellant sloshing parameters by simulation. The method simulates and calculates the liquid sloshing of propellant in the rocket tank to obtain time-domain data of sloshing force and time-domain data of sloshing torque. The n-order Fourier transform is performed on the time-domain data of sloshing force to obtain n-order sloshing frequency. The time-domain data of sloshing force, the time-domain data of sloshing torque and the n-order sloshing frequency are matched by establishing and fitting the corresponding sloshing equation to obtain the centroid position of the n-order sloshing mass of the propellant. The method can effectively solve the technical problems of low accuracy of sloshing parameter acquisition and further affect the precise control of the rocket in the prior art. However, in the preliminary optimization design, the calculation of sloshing parameters depends on the overall and trajectory parameters, which need to be recalculated after adjusting the trajectory, consuming a large amount of computing resources and time cost. SUMMARY

[0004] The present application proposes a liquid sloshing parameter acquisition and anti-slosh design method based on simulation data. After completing the preliminary anti-slosh design, the sloshing simulation is carried out to acquire a large amount of data to form a database. The professional who needs the sloshing parameters uses the database to search and interpolate the required sloshing parameters, thereby solving the problem that the sloshing parameters cannot be quickly and accurately matched in the case of changes in overall and trajectory parameters, realizing rapid automatic calculation and avoiding repeated simulation analysis.

[0005] To solve the problem, the liquid rocket shaking parameter acquisition and anti-shaking design method based on simulation data is proposed, which includes the following steps:

[0006] Anti-shaking plate design, according to the initial trajectory parameters to calculate the initial shaking parameters, determine the anti-shaking design scheme to meet the design requirements, the initial shaking parameters as the basis of the database data for subsequent calculation;

[0007] Shaking simulation, according to the envelope trajectory data, the overall data for batch simulation calculation of shaking parameters, form the basis data for database establishment, and then according to the output of the shaking parameters and the main influencing factors of the shaking parameters to organize the data, form each data;

[0008] Shaking parameter processing, according to the time-force curve obtained by simulation calculation, combined with the abstract shaking parameter theoretical model, data fitting is carried out to identify the key parameters;

[0009] Database establishment, according to the data obtained, the shaking parameter database is established, the database includes propellant, tank diameter, anti-shaking plate position, anti-shaking plate size, overload coefficient, liquid level, shaking frequency, shaking mass, shaking damping, shaking centroid;

[0010] Database use, according to the need, extract the overload coefficient and liquid level information in the overall parameters, and input the propellant, tank diameter, anti-shaking plate position, anti-shaking plate size, find the corresponding data in the database, and then take the liquid level and overload coefficient as variables to interpolate, obtain the shaking parameters including frequency, mass, damping, centroid.

[0011] Further, it also includes

[0012] Database maintenance and update, during the use of the database, the design parameters of the anti-shaking plate including size and position may be modified, the data of the database is supplemented by redeveloping simulation calculation; or, on the basis of test, the shaking parameters or simulation calculation model is corrected, and the data in the database is updated. (Improve the accuracy of the data in the database)

[0013] Further, it also includes

[0014] Database function expansion (upgrade), after the establishment and gradual improvement of the database, the data in the database is used to realize the rapid anti-shaking design and anti-shaking parameter calculation.

[0015] Further, the shaking simulation

[0016] Specifically includes

[0017] In the process of simulating the sloshing parameters, for a certain liquid propellant, the overload coefficient and the liquid level height are the main variables to be considered, so a two-dimensional matrix of overload and liquid level height needs to be constructed first, and the sloshing parameter calculation of the model with anti-sloshing design for the same tank is carried out in an automated batch processing manner. The time-force and time-moment curves are extracted by applying a standard initial excitation. See the related content in the applicant's granted invention patent CN 113553661 B "Method for obtaining rocket propellant sloshing parameters and computer readable storage medium".

[0018] When forming the two-dimensional matrix of overload and liquid level height, the liquid level height should be taken first. In order to be able to take the liquid level height with the smallest damping as much as possible, the interval should be no more than 0.05R, R being the tank radius; and the interval of the overload coefficient is generally 0.3-0.6 according to the liquid level height and the overload coefficient envelope at that height.

[0019] Further, the sloshing simulation

[0020] Specifically, it further includes

[0021] On the basis of the foregoing liquid level height selection, a plurality of liquid level height points should also be calculated between the two liquid level heights with the lowest damping according to the calculation results, so that the results contain data with the lowest damping; if the anti-sloshing plates are arranged periodically, then the position of the lowest damping relative to the position of the previous anti-sloshing plate remains unchanged, and through the sloshing parameters within a period, the relationship of the liquid level with the smallest damping is found and directly reflected in the liquid level height matrix.

[0022] Further, the abstract sloshing parameter theoretical model in the sloshing parameter processing

[0023] Specifically, it includes

[0024] In order to facilitate the control system to analyze the sloshing parameters, the sloshing system is equivalent to a "spring-damping-mass" model, and the mathematical model is as follows:

[0025] The sloshing force generated by the sloshing part of the liquid can be represented as:

[0026]

[0027] In the formula:

[0028] A n - the sloshing amplitude of the n-th order sloshing;

[0029] w n - the n-th order sloshing frequency;

[0030] ζ n - the n-th order sloshing damping;

[0031] m nn order sway mass

[0032] t - time

[0033]

[0034] wherein:

[0035] xn0 - n order sway initial lateral displacement

[0036] v n0 n order sway initial velocity

[0037] The sway moment can be expressed as:

[0038]

[0039] wherein:

[0040] h n n order sway mass center position

[0041] Using the above sway force and moment formulas to fit the sway force and sway moment, the corresponding sway parameters can be identified; from the sway amplitude formula, it can be seen that the size of the sway amplitude is determined by the size of the initial excitation applied;

[0042] Since the first order sway occupies the main component in the sway of the storage tank, the above formula can be replaced by the first order sway, and the above formula can be modified as:

[0043]

[0044]

[0045]

[0046] Therefore, in the simulation, by obtaining the sway force and sway moment, and combining data fitting, the sway frequency, sway damping, sway mass, and sway mass center can be obtained.

[0047] Further, the sway parameters are obtained by interpolation with liquid level height and overload coefficient as variables, and the specific interpolation method includes

[0048] Linear interpolation is performed by a two-dimensional matrix.

[0049] Further, the database is maintained and updated to reduce data calculation

[0050] Specifically, it includes

[0051] Data updating and supplementing exist in the following two forms:

[0052] If the anti-sloshing plate only partially changes, only the affected liquid level needs to be calculated, and the partial data needs to be supplemented, and the affected range is determined according to the anti-sloshing plate information recorded in the database;

[0053] If the anti-sloshing plate is translated up and down as a whole, and the relative position does not change, then according to the liquid level and the relative position of the anti-sloshing plate, the column segment part data in the storage tank is processed to obtain the calculation of the affected part, and the data is supplemented.

[0054] Further, it also includes

[0055] The specific steps of the anti-sloshing optimization design using the database are as follows:

[0056] Through the design index of the demand end, the existing database is used to realize the anti-sloshing preliminary design under the condition of rapid parameter matching.

[0057] Then, according to the actual situation, the simulation calculation is adjusted and supplemented, and the database is perfected.

[0058] On the basis of the accumulation of the database data, the time-varying parameterized demand is matched for the anti-sloshing design, so as to realize the optimization design.

[0059] The embodiment of the application also provides a computer readable storage medium, which comprises a stored program, wherein the program executes the liquid rocket sloshing parameter acquisition and anti-sloshing design method based on simulation data.

[0060] Compared with the prior art, the above technical scheme conceived by the application can achieve the following beneficial effects:

[0061] A liquid sloshing parameter acquisition and anti-sloshing design method based on simulation data, after completing the preliminary anti-sloshing design, carries out sloshing simulation, acquires a large amount of data, forms a database, and uses the database to search and interpolate the required sloshing parameters, so as to solve the problem that the sloshing parameters cannot be quickly and accurately matched in the case of changes in the overall and trajectory parameters, realize rapid automatic calculation, and avoid repeated simulation analysis.

[0062] In summary, the method proposed in the present application can absorb the adaptability of simulation corresponding to various anti-slosh design data acquisition, and quickly realize the acquisition of sloshing parameters in the later iteration, thereby improving the iteration efficiency, saving time cost, and having certain engineering application value. Especially combined with the advantages of simulation calculation of calculating sloshing parameters under different anti-slosh plates, and on the basis of data, the fast sloshing parameter calculation under different overall and trajectory parameters is realized, the demand of fast iteration of trajectory is met, and the anti-slosh plate can be quickly designed and optimized based on the existing data according to the demand of anti-slosh parameters. BRIEF DESCRIPTION OF DRAWINGS

[0063] Figure 1 The method steps of the present application are shown in the figure;

[0064] Figure 2 The simulation calculation model is shown in the figure;

[0065] Figure 3 The liquid level under initial excitation is shown in the figure;

[0066] Figure 4 The equivalent spring oscillator model of the sloshing parameter is shown in the figure;

[0067] Figure 5 The sloshing force curve is shown in the figure;

[0068] Figure 6 The sloshing moment curve is shown in the figure;

[0069] Figure 7 The anti-slosh plate position is shown in the figure;

[0070] Figure 8 The anti-slosh parameter data use flow logic diagram is shown in the figure;

[0071] Figure 9 The anti-slosh plate design based on simulation data is shown in the figure;

[0072] Figure 10 In the example, for a certain liquid propellant, the two-dimensional liquid level height and overload matrix formed in the process of the missile body flight are assumed;

[0073] Figure 11 In the example, the two-dimensional liquid level height and overload matrix are supplemented and improved. DETAILED DESCRIPTION

[0074] With reference to the accompanying drawings, the technical solutions in the embodiments of the present application will be clearly and completely described in the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by a person of ordinary skill in the art without creative effort belong to the scope of protection of the present application.

[0075] The embodiments of the present application provide a liquid rocket sloshing parameter acquisition and anti-sloshing design method based on simulation data, including the following steps

[0076] Step S1:

[0077] Anti-sloshing plate design: initial sloshing parameters are calculated according to initial trajectory parameters, and an anti-sloshing design scheme meeting design requirements is determined, and the initial sloshing parameters are used as the basis of the database basic data for subsequent calculation; the anti-sloshing design is generally the design of the anti-sloshing plate in the tank, which is equivalent to setting a plate in the tank to prevent the liquid from sloshing up and down, and generally includes the axial position, circumferential position, size of the anti-sloshing plate, etc.

[0078] Step S2:

[0079] Sloshing simulation: batch simulation calculation of sloshing parameters is performed according to the envelope trajectory data and overall data to form the basic data for establishing the database, and the data is arranged according to the output sloshing parameters and the main influencing factors of the sloshing parameters to form a piece of data; each piece of data includes a certain time, and the liquid level height, overload (overload refers to the overload of the entire rocket body, that is, the large overload environment of the tank and the liquid), sloshing frequency, sloshing damping, sloshing mass and sloshing centroid corresponding to the certain time;

[0080] The sloshing simulation specifically includes

[0081] In the process of simulating and calculating the sloshing parameters, for a certain determined liquid propellant, the overload coefficient and the liquid level height are the main variables to be considered, so it is necessary to first construct a two-dimensional matrix of the overload and the liquid level height, and to calculate the sloshing parameters of the model with anti-sloshing design for the same tank by using automatic batch processing. The time-force and time-moment curves are extracted by applying standard initial excitation.

[0082] When the two-dimensional matrix of the overload and the liquid level height is formed, the liquid level height should be taken first, and in order to take the liquid level height with the smallest damping as much as possible, the interval should be no greater than 0.05R, R being the radius of the tank; and the interval of the overload coefficient is generally 0.3-0.6 according to the liquid level height and the overload coefficient envelope at the height.

[0083] Sloshing simulation

[0084] Specifically, it also includes

[0085] On the basis of the above-mentioned liquid level height selection, a plurality of liquid level points should be calculated between the two liquid level heights with the lowest damping according to the calculation result, so that the result contains data with the lowest damping; if the anti-sloshing plates are arranged periodically, then the position of the lowest damping relative to the position of the previous anti-sloshing plate remains unchanged, and through the sloshing parameters in a period, the relationship of the liquid level with the minimum damping is found and directly reflected in the liquid level height matrix.

[0086] Step S3:

[0087] Sloshing parameter processing: according to the time-force curve obtained by simulation calculation, combined with the abstract sloshing parameter theoretical model, the key parameters including the sloshing parameters and some others are identified through data fitting. It is equivalent to knowing the expression of the curve and identifying all the parameters; see the method in the applicant's granted invention patent CN 113553661 B “Method for obtaining sloshing parameters of rocket propellant and computer readable storage medium”;

[0088] Abstract sloshing parameter theoretical model in sloshing parameter processing

[0089] Specifically includes

[0090] In order to facilitate the control system to analyze the sloshing parameters, the sloshing system is equivalent to a “spring-damping-mass” model, and the mathematical model is as follows:

[0091] The sloshing force generated by the sloshing part of the liquid can be expressed as:

[0092]

[0093] In the formula:

[0094] A n — Sloshing amplitude of n-order sloshing;

[0095] w n — n-order sloshing frequency;

[0096] ζ n — n-order sloshing damping;

[0097] m n — n-order sloshing mass;

[0098] t— time;

[0099]

[0100] In the formula:

[0101] xn0— n-order initial lateral displacement;

[0102] v n0 — n-order initial velocity.

[0103] The swaying torque can be expressed as:

[0104]

[0105] In the formula:

[0106] h n —Position of the center of mass of the nth-order wobbling motion;

[0107] By fitting the swaying force and torque using the above formulas, the corresponding swaying parameters can be identified. From the formula for swaying amplitude, it can be seen that the magnitude of the swaying amplitude is determined by the magnitude of the applied initial excitation.

[0108] Since the first-order swaying constitutes the majority of the tank's swaying, the above formula can be replaced by the first-order swaying motion, and thus the formula can be modified as follows:

[0109]

[0110]

[0111]

[0112] Therefore, by obtaining the swaying force and swaying torque in the simulation, and then combining the data fitting, the swaying frequency, swaying damping, swaying mass, and swaying center of mass can be obtained.

[0113] In summary, the shaking simulation calculation process is as follows:

[0114] First, a simulation model is established based on the anti-sway plate design and the storage tank, such as... Figure 2 As shown;

[0115] Set the liquid level and overload parameters, the liquid is... Figure 2 The 101 mark in the text:

[0116] Set the initial incentive as follows: Figure 3 The initial wave height is typically set to Φ = 5°.

[0117] Simulation calculations were performed, showing the liquid surface swaying left and right over time. The curves of the swaying force and torque exerted by the liquid on the tank over time were extracted, as shown in the figure. Figure 5 , Figure 6 As shown. After obtaining the curve described above, use formula F 晃 M 晃 The least squares method is used to fit and obtain the undetermined coefficients in the equation, thereby obtaining the sway parameters.

[0118] Step S4:

[0119] Database establishment, a database of sloshing parameters is established according to the data obtained, and the database includes propellant, tank diameter, slosh plate position, slosh plate size, overload coefficient, liquid level height, sloshing frequency, sloshing mass, sloshing damping, and sloshing centroid.

[0120] Step S5:

[0121] Database use, the overload coefficient and liquid level height information are extracted in the overall parameters as needed, and the propellant, tank diameter, slosh plate position, and slosh plate size are input, and the liquid level height and overload coefficient are used as variables to find the corresponding sloshing parameter data in the database or to obtain the corresponding sloshing parameter data by interpolation, and the sloshing parameters include sloshing frequency, sloshing damping, sloshing mass, and sloshing centroid;

[0122] The liquid level height and overload coefficient are used as variables to interpolate the sloshing parameters, and the specific interpolation method includes linear interpolation through a two-dimensional matrix.

[0123] For a certain liquid propellant, the overload coefficient and liquid level height are the main variables to be considered, so it is necessary to first construct a two-dimensional matrix of the overload and liquid level height, and to calculate the sloshing parameters of the model designed with sloshing prevention for the same tank by using an automated batch processing method. The time-force and time-moment curves are extracted by applying a standard initial excitation, and the specific method is described in the patent CN 113553661 B "Method for obtaining rocket propellant sloshing parameters and computer readable storage medium".

[0124] For example, for a certain liquid propellant, assuming that during the flight of the rocket body, the tank radius is 1 m, the slosh plate is a semicircular type with a radius of 0.3 m, the position is at 8 m, 7 m, 6 m, 5 m, and 4 m, the liquid level height decreases from 8 m to 6 m, and the overload is from 2 g to 4 g, the two-dimensional liquid level height and overload matrix is formed as shown below. Figure 10 As shown in the figure, the gray part is the two-dimensional matrix intersection point that needs to be calculated, and the engine thrust and the corresponding liquid level rocket body mass affect the range of the overload that can be changed at the corresponding liquid level height.

[0125] For each two-dimensional matrix intersection point, a set of sloshing parameters can be obtained, and the data format is as follows:

[0126]

[0127] At 7.45 m and 7.40 m, the damping is found to be 0.88% and 0.89%, respectively, in order to confirm the minimum damping, the data at liquid level heights of 0.74 m and 0.72 m need to be supplemented and calculated again, and supplemented to the database as follows:

[0128]

[0129] So it can be basically confirmed that the minimum damping is 0.87%, at a distance of 0.56m from the last anti-sloshing plate. Since the anti-sloshing plates are arranged periodically, it can be inferred that the minimum damping occurs at liquid level heights of 7.44m, 6.44m, 5.44m, and 4.44m, thereby supplementing and perfecting the two-dimensional liquid level height and overload matrix, as shown in the matrix; after finding the relationship between the minimum damping liquid level, it is directly reflected in the liquid level height matrix. Figure 11

[0130] Further, specific interpolation methods are as follows:

[0131] For example, the search data is as follows, which is not directly included in the database, but is within the envelope range of the database:

[0132]

[0133] Then, according to the characteristics of the sloshing parameters, they are processed respectively:

[0134] 1. The sloshing frequency is most affected by the overload, so the influence of the liquid level height is ignored, and linear interpolation is performed according to the overload ω, and the calculation process is as follows

[0135] ω(2.2g) = 0.2*(ω(2.3g)-ω(2.0g)) / (2.3-2);

[0136] 2. The sloshing damping is most affected by the liquid level height, and the influence of the overload is ignored, and linear interpolation is performed according to the liquid level height;

[0137] 3. The sloshing mass is most affected by the liquid level height, and the influence of the overload is ignored, and linear interpolation is performed according to the liquid level height;

[0138] 4. The sloshing mass center is most affected by the liquid level height, and the influence of the overload is ignored, and linear interpolation is performed according to the liquid level height;

[0139] After combining the above four processing processes, the corresponding sloshing parameters can be obtained by linear interpolation after inputting the liquid level height of 7.98m and the overload of 2.2g.

[0140] Step S6:

[0141] It also includes

[0142] Database maintenance and update: during the use of the database, as the iteration of the parameter professional needs, the design parameters of the anti-sloshing plate including the size and position may be modified, and the data of the database is supplemented by redeveloping simulation calculation; or, on the basis of the test, the sloshing parameters or the simulation calculation model are corrected, the data in the database is updated, and the accuracy of the data in the database is improved, so as to reduce the calculation of the data;

[0143] Specifically, it includes​

[0144] Data update and supplement exist in the following two forms:

[0145] If the anti-sloshing plate only changes partially, only the affected liquid level needs to be calculated, and partial data needs to be supplemented. The affected range is determined according to the anti-sloshing plate information recorded in the database;

[0146] If the anti-sloshing plate is translated up and down as a whole, and the relative position does not change, the column segment data in the tank is processed according to the liquid level and the relative position of the anti-sloshing plate to obtain the data that needs to be recalculated and supplemented.

[0147] Step S7:

[0148] It also includes

[0149] Database function expansion: after the database is established and gradually improved, the data in the database is used to realize rapid anti-sloshing design and anti-sloshing parameter calculation. The database is used for anti-sloshing optimization design, and the specific steps are as follows:

[0150] Through the design index of the demand end, the existing database is used to realize the preliminary design of anti-sloshing under rapid parameter matching. If the corresponding data cannot be matched, a new set of data is designed, that is, the database can also be adjusted according to the actual situation to supplement the simulation calculation and improve the database. After multiple rounds of design and technology, a large amount of data is accumulated. According to the overall professional requirements, the database is searched to guide the anti-sloshing plate design, and the matching sloshing parameters and anti-sloshing plate design parameters are directly output;

[0151] For example, at the 20th moment in the flight process, the liquid level height is 7m, and the liquid oxygen damping is greater than 1.1%. At the 30th moment, the liquid level height is 6.5m, and the damping required is greater than 0.9%. The following data is obtained by searching:

[0152]

[0153] By comparing, it is found that the above two data meet the overall demand. The anti-sloshing plate position and size are read from the data, so that the anti-sloshing plate from this part of the tank needs to be designed to have a position of 8m, 7m, 6m and 5m, and a size of a semicircular radius of 0.3m. Moreover, the sloshing data corresponding to the anti-sloshing plate and the overall parameters in the database can be directly output to realize rapid design and sloshing parameter calculation.

[0154] On the basis of the accumulation of database data, the time-varying parameterized requirements are matched for anti-sloshing design, so as to realize optimization design.

[0155] In another aspect, the embodiment also provides a computer readable storage medium, which comprises a stored program. When the program runs, the above-mentioned liquid rocket sway parameter acquisition and anti-sway design method based on simulation data is executed.

Claims

1. A method for obtaining swaying parameters and designing anti-swaying mechanisms for liquid rockets based on simulation data, characterized in that... Includes the following steps: The anti-sway plate design calculates the initial sway parameters based on the initial ballistic parameters, and determines the anti-sway design scheme that meets the design requirements. The initial sway parameters serve as the basis for the subsequent calculation database. Sway simulation involves batch simulation calculation of sway parameters based on the overall envelope and ballistic data to form the basic data for establishing the database. Then, the data is organized according to the output sway parameters and the main influencing factors affecting the sway parameters to form individual data. The swaying parameter processing involves using the time-force curve obtained from simulation calculations, combined with an abstract theoretical model of swaying parameters, to perform data fitting and identify key parameters. Establish a database based on the acquired data. The database contains data such as propellant, tank diameter, anti-sway plate position, anti-sway plate size, overload factor, liquid level, sway frequency, sway mass, sway damping, and sway center of mass at a certain moment. The database is used to extract the overload factor and liquid level information from the overall parameters as needed, and input the propellant, tank diameter, anti-sway plate position and anti-sway plate size. The corresponding swaying parameter data is found in the database, and then the liquid level and overload factor are used as variables for interpolation to obtain the swaying parameters, including swaying frequency, swaying mass, swaying damping and swaying center of mass. The abstract theoretical model of sway parameters in the sway parameter processing specifically includes: To facilitate the analysis of sway parameters in the control system, the sway system is equivalent to a "spring-damping-mass" model, and the mathematical model is as follows: The sloshing force generated by shaking a portion of the liquid can be expressed as: ， In the formula: —The amplitude of the nth-order oscillation; —nth order oscillation frequency; — nth-order sway damping; — nth-order swaying mass; t --time; ， In the formula: —Initial lateral displacement of the nth-order swaying motion; —Initial velocity of the nth-order oscillation; The swaying torque can be expressed as: ， In the formula: —Position of the center of mass of the nth-order wobbling motion.

2. The method for obtaining liquid rocket swaying parameters and designing anti-swaying techniques based on simulation data according to claim 1, characterized in that... Also includes: Database maintenance and updates involve modifying the design parameters of the anti-sway plate, including its size and location, during database use, and supplementing the database data by re-conducting simulation calculations; or, based on experiments, correcting the swaying parameters or simulation calculation models and updating the data in the database.

3. The method for obtaining liquid rocket swaying parameters and designing anti-swaying techniques based on simulation data according to claim 2, characterized in that... Also includes: Database functionality is expanded so that, after the database is established and gradually improved, the data in the database can be used to achieve rapid anti-sway design and anti-sway parameter calculation.

4. The method for obtaining liquid rocket swaying parameters and designing anti-swaying techniques based on simulation data according to any one of claims 1-3, characterized in that... The shaking simulation specifically includes: In the simulation calculation of sloshing parameters, for a certain liquid propellant, the overload coefficient and liquid level height are the main variables to be considered. Therefore, it is necessary to first construct a two-dimensional matrix of overload and liquid level height, and use an automated batch processing method to calculate the sloshing parameters of the same tank with anti-sloshing design; and extract the time-force and time-torque curves by applying a standard initial excitation. When forming the two-dimensional matrix of overload and liquid level height, the liquid level height should be taken first. In order to obtain the liquid level height with the minimum damping as much as possible, the interval should generally not be greater than 0.05R. Then, the interval of the overload coefficient should be taken according to the liquid level height and the envelope of the overload coefficient at that height, which is generally 0.3 to 0.

6.

5. The method for obtaining liquid rocket swaying parameters and designing anti-swaying techniques based on simulation data according to claim 4, characterized in that... The shaking simulation specifically also includes: Based on the above liquid level selection, multiple liquid level height points should be calculated between the two liquid level heights with the lowest damping, according to the calculation results, so that the results contain the data of the lowest damping. If the anti-sway plates are arranged periodically, the position of the lowest damping plate remains relatively unchanged relative to the position of the previous anti-sway plate. After finding the relationship of the minimum damping liquid level through the sway parameters within one cycle, it is directly reflected in the liquid level height matrix.

6. The method for obtaining liquid rocket swaying parameters and designing anti-swaying techniques based on simulation data according to claim 1, characterized in that... The specific parameters for data fitting and identification include: The swaying force and torque are fitted using the formulas for swaying force and torque to identify the corresponding swaying parameters. From the formula for swaying amplitude, it can be seen that the magnitude of the swaying amplitude is determined by the magnitude of the applied initial excitation. The formula for the swaying force and torque is replaced by a first-order sway, and the formula is modified as follows: ， ， ， Therefore, in the simulation, the swaying force and swaying torque are obtained, and then combined with data fitting, that is, the swaying frequency, swaying damping, swaying mass, and swaying center of mass are obtained.

7. The method for obtaining liquid rocket swaying parameters and designing anti-swaying techniques based on simulation data according to claim 1, characterized in that... The method for obtaining sway parameters by interpolation using liquid level height and overload coefficient as variables includes: Linear interpolation is performed using a two-dimensional matrix.

8. The method for obtaining liquid rocket swaying parameters and designing anti-swaying techniques based on simulation data according to claim 1, characterized in that... The database maintenance and updates, to reduce data computation, specifically include: Data updates and supplements take the following two forms: If only part of the anti-sway plate changes, then only the affected liquid level needs to be calculated and some data needs to be added. The affected range is determined based on the anti-sway plate information recorded in the database. If the anti-sway plate is moved vertically as a whole while its relative position remains unchanged, then the data of the column section in the tank is processed based on the liquid level and the relative position of the anti-sway plate. For areas with a significant impact, calculations need to be performed and supplementary data obtained.

9. The method for obtaining liquid rocket swaying parameters and designing anti-swaying techniques based on simulation data according to claim 1, characterized in that... This also includes using databases for anti-sway optimization design, with the following specific steps: By leveraging design metrics from the demand side and utilizing existing databases, we can achieve a preliminary anti-sway design with rapid parameter matching. Further adjustments will be made based on the actual situation, supplementary simulation calculations will be performed, and the database will be improved. Based on the accumulation of comprehensive database data, anti-sway design is matched to time-varying parameterized requirements to achieve optimized design.

10. A computer-readable storage medium, characterized in that... The computer-readable storage medium includes a stored program, wherein the program, when executed, performs the liquid rocket sway parameter acquisition and anti-sway design method based on simulation data as described in any one of claims 1 to 9.

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