Study On Opening Process Characteristic And Sealing Performance Of Check Valve

As a basic component with simple structure,good sealing and no dead zone,oneway valve is widely used in pneumatic transmission and control system,mainly controlling the pressure,flow and flow direction of the system.However,in practical engineering,the unreasonable internal structure design of the check valve may cause vortex or high-frequency vibration of the valve core when the fluid passes through at high speed,resulting in noise and other problems.With the wide use of one-way valve in automobile pneumatic braking system,the performance requirements of one-way valve are higher and higher.Therefore,it is of great significance to study the flow field characteristics,valve core vibration characteristics and sealing performance of one-way valve during opening.The main research of this paper are as follows:(1)The steady-state simulation of the internal flow field of the check valve under different opening is carried out by Fluent software,and the distribution of pressure field,velocity field and turbulent kinetic energy in the internal flow field are analyzed.Through the study,find out the fluid vortex region and the reason,then improve the internal structure.(2)Based on the dynamic grid technology,the opening process of the check valve is dynamically simulated in fluent.It is found that the valve core produces high-frequency vibration in the opening process,and the convergence speed of the displacement curve is slow.Aiming at the problem of spool vibration,the dynamic model of spool is established,and the simulation model is established in Simulink.The influence of various parameters of one-way valve on spool vibration characteristics is studied.(3)Based on the application scenario of check valve,an energy supply system model was established in Amsim,and the influence of key parameters of check valve on charging speed was studied.The Co-simulation platform of Amesim and Isight is built to optimize the matching of key parameters.(4)The O-shaped rubber sealing ring of check valve is simulated in workbench,and the influence of compression,medium pressure and material hardness on sealing property of rubber ring was studied.Through the research and analysis,the beneficial conclusion for the design of check valve is obtained:(1)By analyzing the flow field data of the improved check valve,it can be found that the energy loss of the fluid flowing through the improved check valve is reduced.(2)By studying the influence factors of the vibration characteristics of the valve core,the influence rules of various parameters on the displacement of the valve core are obtained.It is found that the damping length determined by the valve structure is an important factor to reduce the vibration of the valve core quickly,which has guiding significance for the design of the one-way valve structure in the future.(3)Through the optimal matching of the parameters of the check valve,the system improves the charging speed of the air cylinder.(4)After the study of the sealing ring,it is found that the compression of the sealing ring should be controlled within 0.5mm,the medium pressure should be controlled below 1MPa,and the surface hardness of the material should be selected between 60 HA and 65 HA.