The Research Of High Adjustable Ratio Ball Valve And Its Resistance To Cavitation-Erosion

Ball valve is one of the many common valve types which widely used in many industries.Adjustable ratio is a core parameter which represents the adjustment accuracy.V-shaped ball valve due to such as machining process limitations,the highest adjustable ratio is only approximately 30-50,this subject designs a special structure ball valve with an extremely high adjustable ratio,and analyzes its characteristic of cavitation and erosion.Based on the transformation of spherical projection and regular polyhedron spherical meshing method,the optimal adjustable ratio valve core structure is designed and calculated,and a transparent high adjustable ratio ball valve based on the bionic seat structure is designed and assembled.The incision of the ball valve core is designed,which basis to the transformation of the triangle projection onto the spherical surface,and the regular polyhedron spherical meshing method is used to solve the equivalent cross-sectional area₂A,the number of micro elementsn,and the area of micro elementsΔs.Using Matlab to develop the ball spool modeling and calculation software,it takes the radius of the valve pipeline r and the deflection angle of the valveθstem as design variables and the adjustable ratio value as the objective function.It can achieve the purpose of automatically completing the ball valve core calculation and modeling work given any input independent variable（r,θ）.The maximum adjustable ratio spool structure is designed which flow characteristic curve is drawed,.The valve core in physical form is designed with the constraint of driving torque,keyway wall thickness,required compensation surface,strength support.An engineering mapping with its similarity analysis between shellfish and ball valve seat is established,a new valve seat structure based on special material is designed,and the valve is designed as a whole.The adjustable ratio is simulated with different openings and pressure differences.The characteristics of cavitation and erosion of different bionic structures is analyzed,which shows the improvement of the bionic valve seat structure on wear.Using ISIGHT software to integrate Solidworks,ICEM,and FLUENT to optimize the seat structure.A DOE experiment is performed to analyze the weight of each variable on the objective function,and MIGA is used to optimize the structure.The hydraulic experimental system was used to set up different test platforms,and the ball valve’s flow characteristics,cavitation characteristics and erosion wear characteristics were experimentally studied.The adjustable ratio and flow characteristics are tested.A cavitation image acquisition system with high-speed camera and a erosion test system were built.According to the experimental results,the improvement of erosion resistance of the bionic valve seat structure was analyzed.