Research On Structure Optimization And Fluid-thermal-structure Coupling Of The Boom Flow Channel In Multi-way Valve For Excavators

The multi-way valve is the core component of excavator hydraulic system,its quality and performance have a crucial impact on the operation performance and reliability of the whole machine.The flow channel structure of the multi-way valve of the excavator is complex and the working environment is random,and the multi-way valve often works in the high pressure and large flow environment,the flow field state parameters such as pressure and velocity change frequently in the valve the pressure,which is easy to cause large pressure loss of the hydraulic system,and increase the reactive power loss of the excavator.The boom is the main bearing part of the excavator,which is often subjected to alternating load and impact load in the process of excavation.Therefore,the structural design of the boom flow channel directly affects the performance and efficiency of the whole machine.This paper takes the boom channel of the multi-way valve of excavator as the research object,based on the analysis of the flow channel pressure loss,the optimization design of the structural parameters is completed by combining the neural network and genetic algorithm,and the fluid-thermal-structure coupling method is used to conduct a multi-physics coupling analysis on the optimal design scheme,and the correctness of the multi-way valve flow field simulation model is verified through the pressure loss bench test.The main research contents of this paper are as follows:Simulation analysis of flow field of the boom flow channel in multi-way valve.The geometric model and finite volume model of multi-way valve boom fluid domain were established,and the six key structural parameters of flow channel are drawn up,through the flow field simulation,the change law of pressure and velocity field of fluid in the multi-way valve boom flow channel and the distribution law of flow channel pressure loss were analyzed.Structure optimization design of boom flow channel in multi-way valve.Based on MATLAB,BP neural network was created and trained to fit the implicit mapping relationship between flow channel structural parameters and pressure loss,and the optimal combination of flow channel structural parameters was determined by using the global optimization property of genetic algorithm.Fluid-thermal-structure coupling simulation and analysis of boom flow channel in multi-way valve.According to the optimal combination of flow channel structural parameters determined based on pressure loss,a fluid-thermal-structure multi-physics coupling simulation model of the boom flow channel in multi-way valve was established by ANSYS Workbench platform to analyze the strength and stiffness of the boom valve body under the combined action of fluid load and heat load,and the rationality of the optimized design scheme was verified.Bench test of boom flow channel in multi-way valve.After the trial production and processing of the multi-way valve sample,the inlet and outlet pressure of the boom flow channel is tested by using the multi-way valve test bench,and the correctness of the simulation model was verified by comparing with the pressure loss of the simulation model.