Method for optimizing structural parameters of honeycomb bottom plate of pump unit under multiple excitation

Abstract

The invention belongs to the field of underwater pump set vibration reduction design, and discloses a method and system for optimizing structural parameters of a honeycomb bottom plate of a pump set under multiple excitation, and the method comprises the steps: obtaining time domain data of periodic forces on a plurality of contact surfaces of each part of the pump set and the honeycomb bottom plate, and taking the time domain data as excitation loads on the surface of the honeycomb bottom plate of the pump set; establishing a honeycomb bottom plate finite element model; setting a plurality of groups of simulation test schemes, substituting parameter combinations into the honeycomb bottom plate finite element model, and calculating corresponding performance evaluation index data; constructing a mathematical mapping response surface model between the structure parameter optimization design variable and the optimization target performance evaluation index; the significance of the constructed response surface model is checked, if the requirement is met, the optimal structure parameter combination is solved, and honeycomb bottom plate structure parameter optimization design is achieved; and if not, increasing the number of the test sample points for design, and repeating the related steps until the requirements are met. The method better meets the requirements of practical engineering problems, and the optimization design result of the structural parameters of the metal honeycomb bottom plate is more accurate and reliable.

Description

Technical Field

[0001] The present invention belongs to, but is not limited to, the technical field of vibration reduction design of underwater pump sets, and particularly relates to a method and system for optimizing the structural parameters of a honeycomb bottom plate of a pump set under multiple excitations. Background Art

[0002] As a naval warfare equipment, an underwater vehicle has become the main combat force of modern navies due to its characteristics such as concealment, strong maneuverability, long endurance, and strong surprise attack ability. For an underwater vehicle, acoustic stealth performance is its greatest feature and advantage, and it is also the source of its deterrence in naval warfare strategy. Optimizing or redesigning pump set equipment with a large contribution to vibration and noise in a submarine into low-vibration and low-noise equipment has become the most important work in the development of naval warfare equipment.

[0003] Metal honeycomb sandwich panels have been widely used in high-tech fields such as aerospace and submarine vehicles due to their characteristics of light weight and high strength, and research has shown that honeycomb sandwich panels have special effects in terms of structural vibration and sound transmission characteristics. There have been many studies on the influence of the honeycomb layer structural parameters of metal honeycomb sandwich panels on their vibration characteristics, but they basically focus on the influence of each parameter of the honeycomb layer on the vibration response and sound transmission of the honeycomb panel, or the vibration test of a metal honeycomb panel under a single excitation. However, when actually applying the metal honeycomb sandwich panel structure to pump set equipment as a bottom plate for vibration reduction optimization, there is currently a lack of specific structural parameter optimization or design methods. Especially when the equipment has a complex structure and generates multiple excitations acting on multiple positions with different dynamic characteristics, it is impossible to guide the design and selection of honeycomb sandwich panels through the current vibration model theories of various honeycomb sandwich panel structural parameters to obtain excellent vibration reduction effects. Inventing a method for optimizing the design of the honeycomb structure parameters of a honeycomb panel is of great significance for the vibration reduction optimization of important equipment and the application in the field of honeycomb sandwich panel vibration.

[0004] In view of the above analysis, the technical problems that urgently need to be solved in the prior art are as follows:

[0005] Considering the structural parameter optimization design of a metal honeycomb bottom plate under multiple excitations generated by a pump set. Summary of the Invention

[0006] Aiming at the problems existing in the prior art, the present invention provides a method and system for optimizing the structural parameters of a honeycomb bottom plate of a pump set under multiple excitations.

[0007] The present invention is implemented as follows. A method for optimizing the structural parameters of a honeycomb bottom plate of a pump set under multiple excitations is characterized in that the method for optimizing the structural parameters of a honeycomb bottom plate of a pump set under multiple excitations specifically includes:

[0008] S1: Define the pump unit type and working principle, conduct kinematic analysis and dynamic load calculation on the main moving parts of the pump unit under rated conditions, and then obtain the time-domain data of the forces on each contact surface between each part of the pump unit and the bottom plate through simulation, experimental measurement or calculation, which is used as the excitation load on the surface of the honeycomb bottom plate of the pump unit.

[0009] S2: Establish a finite element model of the honeycomb bottom plate under actual working conditions. The finite element model simplifies the detailed structure of the pump unit part on the honeycomb bottom plate and only includes parameter settings such as the assembly constraint relationship of the honeycomb bottom plate.

[0010] S3: Determine the structural parameter of the honeycomb layer to be designed as the experimental factor, select the optimization target performance evaluation index, and set several groups of simulation test schemes for the combination of structural parameters.

[0011] S4: With the help of the finite element model of the honeycomb bottom plate in S3, based on the excitation load on the surface of the honeycomb bottom plate calculated in S1, calculate the corresponding performance evaluation index data of different groups of simulation tests.

[0012] S5: Through the sample data in S4, construct a mathematical mapping response surface model between the structural parameter optimization design variables and the optimization target performance evaluation index.

[0013] S6: Conduct a significance test on the response surface model constructed in S5 to judge whether the significance degree meets the requirements. If it meets the requirements, proceed to S7; if it does not meet the requirements, increase the number of experimental sample points for design, and repeat S4 - S6 until the significance degree of the mathematical mapping model between the structural parameter optimization design variables and the optimization target performance evaluation index constructed meets the requirements.

[0014] S7: Based on the mathematical mapping model between the structural parameter optimization design variables and the optimization target performance evaluation index, according to the optimization constraint conditions and optimization target of the pump unit bottom plate, solve the best combination of structural parameters through an algorithm to achieve the optimized design of the honeycomb bottom plate structural parameters.

[0015] Furthermore, the S2 includes the following steps:

[0016] When conducting three-dimensional modeling of the honeycomb bottom plate of the pump unit, separate the honeycomb layer of the bottom plate for independent modeling, and quickly establish multiple groups of finite element models with changed honeycomb bottom plate structural parameters by replacing the three-dimensional models of honeycomb layers with different structural parameters.

[0017] Furthermore, the specific operation of setting the experimental scheme in S3 is to use the central composite design (CCD) method for simulation test design, take the linearly uniform coded level number, and use the Box - Behnken module in Design - Expert software to generate several groups of sample simulation schemes.

[0018] Further, the steps for establishing and calculating the transient response simulation model of the honeycomb bottom plate of the pump group in S4 are as follows:

[0019] Import honeycomb bottom plate models with different structural parameters into the simulation project, set the material distribution according to the design scheme, keep all simulation conditions and settings exactly the same, and directly replace the honeycomb bottom plate models with different structural parameters into the simulation project; calculate the mass of the pump group structure on the bottom plate and set the point mass on the center of gravity to the bottom plate; set the fixed constraint form and parameters of the honeycomb bottom plate according to the actual installation conditions of the pump group; set the force excitation and gravitational action based on the load time-domain data on the surface of the honeycomb bottom plate calculated in S1; set the solution results based on the optimization target performance evaluation index selected in S3; finally, solve and calculate the target performance evaluation index.

[0020] Further, for the mathematical mapping model constructed in S5, first analyze the correlation between the target performance evaluation index obtained in S4 and individual structural parameters, and select a suitable fitting model including linear model, 2FI model, second-order model, third-order model, etc. according to the actual situation to construct the mathematical mapping model.

[0021] Further, in S6, conduct a significance test on the fitting model, and the test methods include goodness-of-fit test (R 2 test) and F test.

[0022] Another object of the present invention is to provide a system for optimizing the structural parameters of the honeycomb bottom plate of the pump group under multiple excitations. The system specifically includes:

[0023] Excitation load calculation module, used to conduct kinematic analysis and dynamic load calculation on the main moving parts of the pump group under rated conditions, and obtain the time-domain data of the forces on each contact surface between each part of the pump group and the bottom plate, as the excitation load on the surface of the honeycomb bottom plate of the pump group;

[0024] Finite element model establishment module, used to establish the finite element model of the honeycomb bottom plate under actual working conditions and simplify the detailed structure of the pump group part on the honeycomb bottom plate;

[0025] Simulation test module, used to calculate the corresponding performance evaluation index data of different groups of simulation tests;

[0026] Mathematical mapping response surface model construction module, used to construct the mathematical mapping response surface model between the structural parameter optimization design variables and the optimization target performance evaluation index;

[0027] Significance test module, used to conduct a significance test on the response surface model to determine whether the significance degree meets the requirements;

[0028] Parameter optimization design module, used to solve the optimal structural parameter combination according to the optimization constraint conditions and optimization objectives of the pump group bottom plate, and realize the optimization design of the structural parameters of the honeycomb bottom plate.

[0029] Combined with the above technical solutions and the technical problems solved, the advantages and positive effects of the technical solutions to be protected by the present invention are as follows:

[0030] The present invention provides a specific implementation scheme for applying a metal honeycomb sandwich panel as the vibration reduction design of the honeycomb bottom plate of a pump unit, which considers the multiple excitation characteristics of the target pump unit and better meets the requirements of actual engineering problems; making the optimized design results of the metal honeycomb bottom plate structure parameters more accurate and reliable.

[0031] The expected benefits and commercial values after the transformation of the technical solutions of the present invention are: The present invention guides the development and design of low-vibration and low-noise pump units, which can be applied to the pump unit product solutions in high-precision and high-tech fields, improving the product strength and commercial value.

[0032] The technical solutions of the present invention fill the technical gaps in the domestic and international industries: The present invention fills the application method of the vibration reduction structure of the metal honeycomb sandwich panel, which can be used as a reference for the bottom plate design optimization in the design of various pump units.

[0033] The technical solutions of the present invention solve the technical problems that people have always been eager to solve but have never succeeded in obtaining:

[0034] The technical solutions of the present invention overcome the technical prejudice: The present invention optimizes the vibration reduction design from the structure part of the pump unit bottom plate, overcoming the technical prejudice in the conventional research that only focuses on the vibration of the rotating body of the pump unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a flowchart of the method for optimizing the structure parameters of the honeycomb bottom plate of the pump unit under multiple excitations provided by the embodiment of the present invention;

[0036] Figure 2 is a module diagram of the system for optimizing the structure parameters of the honeycomb bottom plate of the pump unit under multiple excitations provided by the embodiment of the present invention;

[0037] Figure 3 is a schematic structural diagram of a water hydraulic screw pump applying a metal honeycomb bottom plate provided by the embodiment of the present invention;

[0038] Figure 4 are the optimized design variables of the honeycomb layer structure parameters of the metal honeycomb bottom plate provided by the embodiment of the present invention, where θ is the honeycomb layer angle, h is the rib height, a is the size of the hexagonal unit, and t is the rib thickness;

[0039] Figure 5 is the finite element model of the honeycomb bottom plate of the pump unit provided by the embodiment of the present invention, including the excitation settings of each contact surface on the upper surface and the foot constraints;

[0040] Figure 6 is the comparison of the acceleration responses of the models before and after optimization of the present invention when brought into the pump unit vibration simulation.

[0041] In the figure: 1. Single-screw pump body; 2. Honeycomb bottom plate; 3. Reducer; 4. Motor. Specific embodiments

[0042] In order to make the objectives, technical solutions and advantages of the present invention more clear and understandable, the following further elaborates on the present invention in conjunction with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0043] As Figure 1 shown, the embodiment of the present invention provides a method for optimizing the structural parameters of the honeycomb bottom plate of a pump group under multiple excitations. The method specifically includes:

[0044] S1: Define the type and working principle of the pump group, conduct kinematic analysis and dynamic load calculation on the main moving parts of the pump group under rated conditions, and then obtain the time-domain data of the forces on each contact surface between each part of the pump group and the bottom plate through simulation, experimental measurement or calculation, as the excitation load on the surface of the honeycomb bottom plate of the pump group;

[0045] S2: Establish a finite element model of the honeycomb bottom plate under actual working conditions. The finite element model simplifies the detailed structure of the pump group part on the honeycomb bottom plate and only includes parameter settings such as the assembly constraint relationship of the honeycomb bottom plate;

[0046] S3: Determine the structural parameters of the honeycomb layer to be designed as experimental factors, select the optimization target performance evaluation index, and set several groups of simulation test schemes for the combination of structural parameters;

[0047] S4: With the help of the finite element model of the honeycomb bottom plate in S3, based on the excitation load on the surface of the honeycomb bottom plate calculated in S1, calculate the corresponding performance evaluation index data of different groups of simulation tests;

[0048] S5: Through the sample data in S4, construct a mathematical mapping response surface model between the structural parameter optimization design variables and the optimization target performance evaluation index;

[0049] S6: Conduct a significance test on the response surface model constructed in S5 to judge whether the significance degree meets the requirements. If it meets the requirements, then proceed to S7; if it does not meet the requirements, increase the number of design test sample points, and repeat S4 - S6 until the significance degree of the mathematical mapping model between the structural parameter optimization design variables and the optimization target performance evaluation index constructed meets the requirements;

[0050] S7: Based on the mathematical mapping model between the structural parameter optimization design variables and the optimization target performance evaluation index, according to the optimization constraint conditions and optimization objectives of the pump group bottom plate, solve the best combination of structural parameters through an algorithm to achieve the optimized design of the structural parameters of the honeycomb bottom plate.

[0051] Step S2 includes the following steps:

[0052] When performing 3D modeling on the honeycomb bottom plate of the pump group, the honeycomb layer of the bottom plate is separated and modeled separately. By replacing the 3D models of the honeycomb layer with different structural parameters, multiple groups of finite element models with changed structural parameters of the honeycomb bottom plate can be quickly established.

[0053] The specific operation of setting the experimental scheme in Step S3 is to use the central composite design (CCD) method for simulation test design, take linearly uniform coded levels, and use the Box - Behnken module in Design - Expert software to generate simulation schemes for several groups of samples.

[0054] The steps for establishing and calculating the transient response simulation model of the honeycomb bottom plate of the pump group in Step S4 include the following steps in sequence:

[0055] Import the honeycomb bottom plate models with different structural parameters into the simulation project, set the material distribution according to the design scheme, and all simulation conditions are exactly the same as the settings. Directly replace the honeycomb bottom plate models with different structural parameters into the simulation project; calculate the mass of the pump group structure on the bottom plate and set the point mass on the bottom plate; set the fixed constraint form and parameters of the honeycomb bottom plate according to the actual installation conditions of the pump group; set the force excitation and gravity based on the load time - domain data on the surface of the honeycomb bottom plate calculated in S1; set the solution results based on the optimization target performance evaluation index selected in S3; finally, solve and calculate the target performance evaluation index.

[0056] For the mathematical mapping model constructed in Step S5, first analyze the correlation between the target performance evaluation index obtained in S4 and individual structural parameters, and select a suitable fitting model including linear model, 2FI model, second - order model, third - order model, etc. according to the actual situation to construct the mathematical mapping model.

[0057] In Step S6, perform a significance test on the fitting model. The test methods include goodness - of - fit test (R 2 test) and F - test.

[0058] The present invention provides a specific implementation scheme for the vibration - reduction design of using a metal honeycomb sandwich plate as the honeycomb bottom plate of a pump group device, which considers the actual multiple excitation forms and characteristic influences of the design target pump group, and is more in line with the actual situation; generally taking the vibration response of the bottom plate feet as the design optimization evaluation index also very much conforms to the original intention of the vibration - reduction design, making the optimization design results of the structural parameters of the metal honeycomb bottom plate more accurate and reliable.

[0059] As Figure 2 shown, a system for optimizing the structural parameters of a pump group honeycomb bottom plate under multiple excitations provided by an embodiment of the present invention specifically includes:

[0060] An excitation load calculation module, which is used to perform kinematic analysis and dynamic load calculation on the main moving parts of the pump unit under rated conditions, and obtain the time-domain data of the forces on each contact surface between each part of the pump unit and the bottom plate, as the excitation load on the surface of the honeycomb bottom plate of the pump unit;

[0061] A finite element model establishment module, which is used to establish a finite element model of the honeycomb bottom plate under actual working conditions and simplify the detailed structure of the pump unit part on the honeycomb bottom plate;

[0062] A simulation test module, which is used to calculate the corresponding performance evaluation index data of different groups of simulation tests;

[0063] A mathematical mapping response surface model construction module, which is used to construct a mathematical mapping response surface model between the structural parameter optimization design variables and the optimization target performance evaluation indexes;

[0064] A significance test module, which is used to perform a significance test on the response surface model to judge whether the significance degree meets the requirements;

[0065] A parameter optimization design module, which is used to solve the optimal structural parameter combination according to the optimization constraint conditions and optimization objectives of the pump unit bottom plate, and realize the optimization design of the honeycomb bottom plate structural parameters.

[0066] As Figure 3 , Figure 4 shown, taking the optimization design of the structural parameters of the honeycomb bottom plate of a water hydraulic screw pump as an example, the present invention is further described in conjunction with the attached drawings and embodiments.

[0067] Step 1: Define the type and working principle of the pump unit, perform kinematic analysis and dynamic load calculation on the main moving parts of the pump unit under rated conditions, and then obtain the time-domain data of the forces on each contact surface between each part of the pump unit and the bottom plate through simulation, test measurement or calculation, as the excitation load on the surface of the honeycomb bottom plate of the pump unit;

[0068] In a water hydraulic screw pump, the sources of the exciting forces transmitted to the honeycomb bottom plate are mainly divided into three parts, namely the single screw pump pump body, the reducer and the motor. The reducer and the motor are connected to each other through an elastic coupling and input torque to the screw pump. Due to the high-frequency meshing contact between the large and small gears inside the reducer, it is the main source of part of the high-frequency vibration, and part of the high-frequency excitation is also generated inside the motor. The present invention mainly analyzes the single screw pump and the reducer parts. When performing mechanical analysis on the single screw pump part, it is necessary to analyze each part of the single screw pump shafting one by one, especially the two parts of the rotor and the input shaft. The analysis of the exciting force of the reducer part is obtained through the dynamic simulation calculation of a pair of helical gear meshing.

[0069] After the force analysis of the stator part of the single screw pump pump body, the following main component forces are calculated:

[0070] The radial support force F of the bushing d1The magnitude is 63.2 N;

[0071] The radial component force F of the universal joint w1 The magnitude is 13.6 N;

[0072] The axial component force F of the universal joint w2 The magnitude is 636 N.

[0073] The force on the input end part of the single-screw pump housing mainly has three parts. First, the first part is the additional unbalanced bending moment generated by the universal joint when transmitting torque. The pin-type universal joint has a yaw angle α, and the universal joint will generate a periodic additional bending moment on the input shaft. The stress amplitude is T1tanα. The calculation formula for the deflection angle α is The second part is the bending moment generated by the rotational eccentric force of the universal joint. The calculation formula is In the formula, e is the eccentricity, ω is the rotational speed of the input shaft, r is the eccentricity of the centroid of the universal joint, m is the total mass of the universal joint (including the pin), L is the length of the universal joint, d is the diameter of the universal joint, and ρ is the material density of the universal joint. The third part is the radial component force F of the force of the universal joint w1 The magnitude is 13.6 N. The combined moments of each part are converted into a radial reaction force of 10.2 N on the pump housing by the input shaft, and the direction rotates with the input shaft, opposite to the direction of the reaction force of the rotor on the stator.

[0074] The dynamic excitation on the reducer housing is the four bearing reaction forces M1 to M4 of the two gear shafts of different sizes, which are obtained by simulating and calculating the dynamic meshing forces of the large and small gears.

[0075] Finally, the above calculated dynamic excitations are added to the assembly model of the honeycomb bottom plate, the pump housing, and the reducer housing to calculate the excitation forces on each contact surface of the honeycomb bottom plate.

[0076] In this embodiment, there are many calculation methods in step one, and the calculation content is relatively detailed and accurate. The force analysis and calculation part in step one of the method of the present invention should be determined according to the actual situation.

[0077] Step two: Establish a finite element model of the honeycomb bottom plate under actual working conditions. The finite element model simplifies the detailed structure of the pump group part on the honeycomb bottom plate and only includes parameter settings such as the assembly constraint relationship of the honeycomb bottom plate;

[0078] Establish a finite element model of the honeycomb bottom plate as Figure 5 , separate the honeycomb layer of the bottom plate and replace it with a three-dimensional model of the honeycomb layer with different structural parameters for modeling. Specifically, set the corresponding constraints and contacts of the honeycomb bottom plate, such as the stiffness in three directions of the mounting feet.

[0079] Step three: Determine the structural parameters of the honeycomb layer to be designed as experimental factors, select the optimization target performance evaluation index, and set the simulation test schemes for several groups of experimental factor combinations;

[0080] Select the honeycomb layer of the honeycomb bottom plate as Figure 4 Four structural parameters are taken as experimental factors, namely the honeycomb layer angle (x1), rib thickness (x2), rib height (x3), and hexagonal unit size (x4); the vibration acceleration of the feet (total vibration level) and the total mass of the honeycomb bottom plate are selected as the optimization target performance evaluation indicators. The central composite design (CCD) method is used for the simulation experiment design. The linear and uniform coding levels are taken, and the Box-Behnken module in the Design-Expert software is used to generate several groups of sample simulation schemes, which include four groups of data with only a single parameter changed among some samples for the simple analysis of the single parameter mapping. The optimization constraint conditions for the experimental factors are shown in Table 1.

[0081] Table 1 Optimization constraint conditions

[0082] Design factor Initial value Lower limit of variable Upper limit of variable <![CDATA[x1 / degree]]> 30 0 60 <![CDATA[x2 / mm]]> 10 6 14 <![CDATA[x3 / mm]]> 80 70 90 <![CDATA[x4 / mm]]> 65 55 75

[0083] In this example, the number of experimental sample groups is selected as 20, and the experimental sample data of the simulation scheme are shown in Table 2.

[0084] Step 4: With the help of the finite element model of the honeycomb bottom plate in Step 3, based on the excitation load on the surface of the honeycomb bottom plate calculated in Step 1, calculate the data of the performance evaluation indicators corresponding to different groups of simulation experiments.

[0085] The establishment and calculation of the transient response simulation model of the honeycomb bottom plate of the pump set include the following steps in sequence:

[0086] Import the honeycomb bottom plate models with different structural parameters into the simulation project, and set the material distribution according to the scheme; set the masses of three points on the bottom plate according to the mass and center of gravity of the pump set structure; set the constraints of the honeycomb bottom plate as elastic constraints with stiffnesses of 0.22 N / m, 0.058 N / m, and 0.042 N / m in the x, y, and z directions respectively according to the actual installation conditions of the pump set; set the force excitation and gravity action based on the load time-domain data on the surface of the honeycomb bottom plate calculated in Step 1; set the solution results based on the selected optimization target performance evaluation indicators (vibration accelerations of 6 feet) in Step 3, and the mass of the honeycomb bottom plate is directly obtained from the mass evaluation in the 3D model; finally, solve and calculate the target performance evaluation indicators, and each indicator is shown in Table 2.

[0087] Table 2 Experimental design and results

[0088]

[0089] Step 5: Through the sample data in Step 4, construct a mathematical mapping response surface model between the structural parameter optimization design variables and the optimization target performance evaluation indicators.

[0090] Analyze the test results in Table 2. Among them, the mapping relationship between the honeycomb layer angle (x1) and the vibration acceleration of the bottom plate feet is close to a quadratic curve, and the mapping relationships between the rib thickness (x2), rib height (x3), and hexagonal unit size (x4) and the vibration acceleration of the bottom plate feet are all closer to a linear curve. Therefore, the second-order model fitting is adopted in the embodiment, and the functional expression of its approximate model is

[0091]

[0092] where Y is the response variable (vibration acceleration or mass), X is the independent variable (honeycomb layer angle, rib thickness, rib height, and hexagonal unit size), β0 is the constant offset term, β i 、β ii are the linear offset and second-order offset coefficients, and ε is the error term.

[0093] From this, the relationship between the total vibration level of the mounting feet of the honeycomb bottom plate and the honeycomb layer angle, rib thickness, rib height, and hexagonal unit size is obtained:

[0094] y1 = 0.0003 * x1^2 + 0.0123 * x2^2 + 0.0017 * x3^2 + 0.0020 * x4^2 + -0.0156 * x1 +

[0095] -0.1475 * x2 + -0.2605 * x3 + -0.2743 * x4 + 157.1340

[0096] From this, the relationship between the total mass of the honeycomb bottom plate and the honeycomb layer angle, rib thickness, rib height, and hexagonal unit size is obtained:

[0097] y2 = 0.0005 * x1^2 + -0.0332 * x2^2 + -0.0008 * x3^2 + 0.0051 * x4^2 + -0.0329 * x1 +

[0098] 3.1257 * x2 + 0.5059 * x3 + -1.0259 * x4 + 44.7354

[0099] Step 6: Conduct a significance test on the response surface model constructed in Step 5 to determine whether the significance level meets the requirements. If it meets the requirements, proceed to Step 7; if it does not meet the requirements, increase the number of design test sample points, and repeat Steps 4, 5, and 6 until the significance level of the mathematical mapping model between the optimized design variables of the structural parameters and the performance evaluation index of the optimization target is satisfied;

[0100] The embodiment adopts the goodness-of-fit test (R 2 test) and F test.

[0101] Goodness-of-fit (R2 ) It is used to measure the fitting degree of the regression model to the observed data, and its value ranges from 0 to 1. The closer it is to 1, the better the fitting effect.

[0102] The F-test is used to test the significance of the entire regression model, that is, to judge whether all independent variables have a significant impact on the dependent variable.

[0103] The calculation results of the significance tests of the two response surface model functions of the model are as follows:

[0104] R of the total vibration level response model of the mounting feet 2 value: 0.96059

[0105] F statistic of the total vibration level response model of the mounting feet: 8.488

[0106] p-value of the F-test of the total vibration level response model of the mounting feet: 0.000933

[0107] R of the total mass response model of the bottom plate 2 value: 0.99771

[0108] F statistic of the total mass response model of the bottom plate: 598.9666

[0109] p-value of the F-test of the total mass response model of the bottom plate: 2.0706e-13

[0110] It can be judged that the fitting degree of the honeycomb bottom plate response surface model is good.

[0111] Step 7: Based on the mathematical mapping model between the optimized design variables of the structural parameters and the performance evaluation indexes of the optimization objectives, according to the optimization constraints and optimization objectives of the pump group bottom plate, solve the optimal combination of structural parameters through an algorithm to realize the optimized design of the honeycomb bottom plate structural parameters.

[0112] Taking the four structural parameter intervals determined in Step 3 as the optimization constraint objectives, with the total vibration level of the bottom plate mounting feet and the total mass of the bottom plate as the optimization objectives, use the fmincon function in MATLAB to find the minimum value of the objective function within the given interval, and the results are as follows:

[0113] The combination of structural parameters when the total vibration level of the bottom plate mounting feet is the smallest within the given interval:

[0114] x1 = 30.1286

[0115] x2 = 6.0171

[0116] x3 = 75.8428

[0117] x4 = 68.8139

[0118] The minimum function value: 137.1396 dB.

[0119] The combination of structural parameters when the total mass of the bottom plate is the smallest within the given interval:

[0120] x1 = 30

[0121] x2 = 6

[0122] x3 = 70

[0123] x4 = 75

[0124] The minimum function value: 44.5541 kg.

[0125] Prioritizing the vibration damping effect, the structural parameters of the honeycomb bottom plate are selected as the honeycomb layer angle (x1) 30.1 degrees, the rib thickness (x2) 6 mm, the rib height (x3) 75.8 mm, and the hexagonal unit size (x4) 68.8 mm. A three-dimensional model of the honeycomb bottom plate is re-established, and the total vibration level of the engine mount vibration is obtained through simulation calculation as 137.1152 dB, which only differs from the predicted value of 137.1108 by 0.0032%, and the mass is 49.75 kg.

[0126] Bring the honeycomb bottom plate models before and after optimization into a dynamic model of a screw pump unit, and the vibration acceleration response of the pump unit engine mount is obtained through simulation. Figure 6 For the average acceleration frequency spectrum curve of the engine mount, it can be found that the vibration frequency spectrum characteristics of the pump unit engine mount before and after optimization are similar, and the vibration amplitude decreases slightly in multiple frequency bands after optimization.

[0127] It should be noted that the embodiments of the present invention can be implemented through hardware, software, or a combination of software and hardware. The hardware part can be implemented using dedicated logic; the software part can be stored in a memory and executed by an appropriate instruction execution system, such as a microprocessor or dedicated design hardware. Those of ordinary skill in the art can understand that the above-mentioned devices and methods can be implemented using computer-executable instructions and / or included in the processor control code, for example, such code is provided on a carrier medium such as a disk, CD, or DVD-ROM, a programmable memory such as a read-only memory (firmware), or a data carrier such as an optical or electronic signal carrier. The devices and their modules of the present invention can be implemented by hardware circuits of programmable hardware devices such as very large scale integrated circuits or gate arrays, semiconductors such as logic chips and transistors, or programmable logic devices such as field programmable gate arrays, and can also be implemented by software executed by various types of processors, or can be implemented by a combination of the above hardware circuits and software such as firmware.

[0128] As described above, it is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be covered within the protection scope of the present invention.

Claims

1. A method for optimizing the structural parameters of the honeycomb bottom plate of a pump group under multiple excitations, characterized in that, The method specifically includes the following: S1: Identify the type and working principle of the pump set, conduct kinematic analysis and dynamic load calculation on the main moving parts of the pump set under rated conditions, and then obtain the time-domain data of the forces on each contact surface between each part of the pump set and the bottom plate through simulation, experimental measurement or calculation, which is used as the excitation load on the surface of the honeycomb bottom plate of the pump set. S2: Establish a finite element model of the honeycomb bottom plate under actual working conditions. The finite element model simplifies the detailed structure of the pump set part on the honeycomb bottom plate and only includes parameter settings such as the assembly constraint relationship of the honeycomb bottom plate. S3: Determine the structural parameter of the honeycomb layer to be designed as the experimental factor, select the optimization target performance evaluation index, and set several groups of simulation test schemes for the combination of structural parameters. S4: With the help of the finite element model of the honeycomb bottom plate in S3, based on the excitation load on the surface of the honeycomb bottom plate calculated in S1, calculate the corresponding performance evaluation index data of different groups of simulation tests. S5: Through the sample data in S4, construct a mathematical mapping response surface model between the structural parameter optimization design variables and the optimization target performance evaluation index. S6: Conduct a significance test on the response surface model constructed in S5 to judge whether the significance degree meets the requirements. If it meets the requirements, proceed to S7; if it does not meet the requirements, increase the number of experimental sample points for design, and repeat S4 - S6 until the significance degree of the mathematical mapping model between the structural parameter optimization design variables and the optimization target performance evaluation index constructed meets the requirements. S7: Based on the mathematical mapping model between the structural parameter optimization design variables and the optimization target performance evaluation index, according to the optimization constraint conditions and optimization objectives of the pump set bottom plate, solve the optimal combination of structural parameters through an algorithm to achieve the optimized design of the honeycomb bottom plate structural parameters.

2. The method for optimizing the structural parameters of the honeycomb bottom plate of the pump unit under multiple excitations according to claim 1, characterized in that The following steps are included in S2: When performing 3D modeling of the honeycomb bottom plate of the pump set, separate the honeycomb layer of the bottom plate for independent modeling, and quickly establish finite element models with multiple groups of changed honeycomb bottom plate structural parameters by replacing the 3D models of honeycomb layers with different structural parameters.

3. The method for optimizing the structural parameters of the honeycomb bottom plate of the pump group under multiple excitations according to claim 1, wherein The specific operation of setting the experimental scheme in S3 is to use the central composite design (CCD) method for simulation test design, take linearly uniform coded levels, and use the Box - Behnken module in Design - Expert software to generate simulation schemes for several groups of samples.

4. The method for optimizing the structural parameters of the honeycomb bottom plate of the pump set under multiple excitations according to claim 1, wherein, The steps for establishing and calculating the transient response simulation model of the honeycomb bottom plate of the pump set in S4 are as follows: Import the honeycomb bottom plate models with different structural parameters into the simulation project, set the material distribution according to the design scheme, and all simulation conditions and settings are exactly the same. Directly replace the honeycomb bottom plate models with different structural parameters into the simulation project. Calculate the mass of the pump set structure on the bottom plate and set the point mass of the center of gravity on the bottom plate. Set the fixed constraint form and parameters of the honeycomb bottom plate according to the actual installation conditions of the pump set. Set the force excitation and gravity action based on the load time - domain data on the surface of the honeycomb bottom plate calculated in S1; set the solution result based on the optimization target performance evaluation index selected in S3; finally, solve and calculate the target performance evaluation index.

5. The method for optimizing the structural parameters of the honeycomb bottom plate of the pump set under multiple excitations according to claim 1, characterized in that, For the mathematical mapping model constructed in S5, first analyze the correlation between the target performance evaluation index obtained in S4 and a single structural parameter, and select a suitable fitting model including a linear model, 2FI model, second-order model, third-order model, etc. according to the actual situation to construct the mathematical mapping model.

6. The method for optimizing the structural parameters of the honeycomb bottom plate of the pump set under multiple excitations according to claim 1, wherein, In S6, a significance test is performed on the fitting model, and the test method uses the goodness-of-fit test (R 2 test) and the F test.

7. A system for optimizing the structural parameters of the honeycomb bottom plate of a pump unit under multiple excitations as described in claims 1-6, characterized in that This system specifically includes: An excitation load calculation module, which is used to perform kinematic analysis and dynamic load calculation on the main moving parts of the pump set under the rated working condition, and obtain the time-domain data of the forces on each contact surface between each part of the pump set and the bottom plate, as the excitation load on the surface of the honeycomb bottom plate of the pump set; A finite element model establishment module, which is used to establish a finite element model of the honeycomb bottom plate under the actual working condition and simplify the detailed structure of the pump set part on the honeycomb bottom plate; A simulation test module, which is used to calculate the corresponding performance evaluation index data of different groups of simulation tests; A mathematical mapping response surface model construction module, which is used to construct a mathematical mapping response surface model between the structural parameter optimization design variables and the optimization target performance evaluation index; A significance test module, which is used to perform a significance test on the response surface model to determine whether the significance level meets the requirements; A parameter optimization design module, which is used to solve the optimal structural parameter combination according to the optimization constraint conditions and optimization objectives of the pump set bottom plate, and realize the optimization design of the honeycomb bottom plate structural parameters.

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