Optimal Design Of Multi-way Valve Notches Based On Steady-state Flow Force Analysis

Multi-way valve,as a hydraulic control element,is widely used in the hydraulic transmission system of manufacturing,agricultural and other walking machinery.It is an important industrial basic element.It has the advantages of high space utilization,convenient operation,easy maintenance,etc.At the same time,the control performance of the multi-way valve also has an important impact on the stability and reliability of the hydraulic system.The steady-state flow force is the most critical factor affecting the control performance one.In this paper,the flow field simulation,experimental test and structural optimization are carried out for the U-shaped notches of the multi-way valve spool.The optimal U-shaped notches size combination is solved by the optimization algorithm to meet the flow characteristic curve of the multi-way valve.At the same time,it reduces the steady-state flow force,so that the multiway valve spool has better control performance.Establish a simulation model for preliminary simulation analysis.A three-dimensional model is established based on the physical model of the multi-way valve.The flow field analysis software Fluent is used to simulate the steady-state flow force under different turbulence models,and the simulation results are compared.Comparing the pressure and velocity clouds at different valve openings,a qualitative analysis of the pressure and velocity fields in the valve is performed.The steady-state flow force of the multi-way valve was tested through experiments and compared with the simulation results.Build test stands to test the force of the valve core,the pressure loss of the valve port and the change of the flow rate in the valve under different flow rates.Combined with the simulation data,it is found that the simulation can well simulate the stress of the valve core in the test,and the simulation results are in good agreement with the test results.Among the selected turbulence models,the Realizable k-? model has the highest agreement with the test results.The flow area and steady-state flow force of U-shaped notches with different structures are analyzed.The overflow area of U-shaped notches with different structure sizes was calculated by Matlab and compared.Simultaneously,the steady-state flow force of U-shaped notches with different structural sizes was simulated and analyzed,and the variation rules of the overflow area and steady-state flow force under different notches widths and depths were discussed.The optimization characteristic of the U-shaped notches is optimized with the flow characteristic curve of the multi-way valve and the steady-state flow force.The response surface method was used to fit the objective functions of steady-state flow force and flow.Multi-island genetic algorithm and sequence quadratic programming method are used to determine the optimal solution.While the results obtained satisfy the flow characteristic curve of the original multi-way valve,the steady-state flow force is significantly reduced.The optimization method and optimization process used in this paper have certain guiding significance for the structural design of similar products,as well as the development and research of optimization algorithms.