Simulation And Experimental Study On Cavitation And Noise Of Hydraulic Cone Valve

The hydraulic cone valve is a kind of hydraulic valve with common structure,it has the advantages of line sealing,no dead time,sensitive action,high flow capacity performance.But because the flow state of internal fluid of cone valve is very complicated,so serious cavitation and noise will occur,therefore,the cone valve stability is affected,and a long time of cavitation accumulation will form corrosion on the spool surface,lead to affect precision,cause cone valve failure.So it is very meaningful to study the cavitation and noise of hydraulic cone valve.Aiming at the mechanism of cavitation and noise,the types and mathematical models of the cavitation and noise of the hydraulic cone valve are introduced.According to the fluid mechanics theory and the internal flow field structure of cone valve,the turbulence model,the two phase flow model,the near wall function,the cavitation model and the acoustic model in the numerical simulation are given.It is the theoretical basis of simulation research on cavitation and noise.According to the flow passage shape,the flow area formula and the flow formula are established,and the axial hydraulic force formula and radial force formula are deduced.Then the solid model of the internal flow field of cone valve is established by using UG software,and the simulation of the hydrodynamic force of the cone valve is carried out based on the CFD technology,and the simulation results are verified by AMESim software.Finally,the radial offset value of the spool is estimated by the radial force equation.The radial force of the fluid on the valve core can not completely offset each other,so the displacement of the valve core in the radial direction is considered.The internal flow field models under different conditions are modeled respectively,and the mesh models are divided by using ICEM-CFD software.Based on the FLUENT simulation software,the turbulent model,the RNG turbulence model,the cavitation model and the noise model are selected to study the numerical simulation of the two-phase flow.The variation of cavitation and noise under four factors,such as radial offset,half cone angle,opening degree and back pressure,is obtained.Finally,the results are analyzed by combining with the cavitation volume fraction,the noise decibel variation curve and the distribution of pressure,velocity,cavitation and noise in the inner flow field.An experimental platform for cavitation and noise of the hydraulic cone valve was built.In order to observe the cavitation phenomenon in cone valve experiment intuitively,the transparent organic glass material was used to process the cone valve block.According to the photographs of cavitation and the measured decibel value of the noise in the experiment,it is shown that the change rule of the cavitation intensity and the change trend of the noise coincide with the simulation results,the correctness of the simulation results is verified.