Dynamic Analysis And Flow Field Simulation Of High Speed Valve In Radial Piston Emulsion Pump

The flow demand of the hydraulic support often changes dynamically with the process of the support moving,lifting and falling,with large amplitude,high frequency and strong randomness.The emulsion pump widely adopts valve distribution method.The fast response and precise control of the valve are the key to the efficient operation of emulsion pump.The response frequency of the existing valve is low,and the lag is obviously due to the structural constraints.At the same time,the high frequency action of distribution valve has more prominent influence on the service life of valve core and valve seat,and cavitation on the volumetric efficiency.This research analyzes the problems of the existing hydraulic pump distribution valve.Combining the characteristics of characteristics of working conditions in the coal mine industry.On the basis of the kinematic analysis of the plunger emulsion pump,it adopts three high-speed valve structure of ball valve,cone valve and flat valve..The main parts of the valve,the valve core and the spring are designed,and the comparative analysis of the valve core quality,impact,contact surface,processing difficulty,etc.is provided.It provides a basis for the selection of the valve structure.Based on the dynamic model of the valve,,the static and dynamic characteristics of the distribution system are analyzed.Meanwhile,the dynamic equilibrium equation is established to analyze and calculate the spring force,viscous resistance,hydraulic pressure,etc.Based on the classical control theory,the differential equation of the system motion is established.And the time response of the valve spool opening and closing process is theoretically analyzed,which lays a theoretical foundation for studying the response characteristics of the flow distribution system.The AMESim software was used to model and simulate the emulsion pump system with three distribution valve structures,and the effects of the pump speed and the three valve core structures on the system response characteristics were compared and analyzed.And The simulation results show that: the higher the speed of the emulsion pump,the higher the structure and life requirements of the distribution valve,and the cone valve is more suitablefor the high-speed valve distribution system.The simulation results show that:the higher the speed of the emulsion pump,the higher the structure and life requirements of the distribution valve,and the cone valve are more suitable for the high-speed valve distribution system.The simulation results show that: the higher the speed of the emulsion pump,the higher the structure and life requirements of the distribution valve,and the cone valve is more suitable for the high-speed valve distribution system.Based on CFD technology,the flow field in the valve is simulated using fluent software,and the flow field characteristics of the existing cone valve structure and streamline cone valve structure designed in this resserch are compared and analyzed,that is,velocity vector distribution,pressure gradient and gas phase distribution.With the goal of the best flow characteristics and the weakest cavitation,the structure of the streamlined valve core is optimized.Further simulation results show that: compared with the existing cone valve structure,the streamline cone valve structure has a smaller fluid pressure drop,gas distribution area and gas volume fraction in the flow channel.The cavitation phenomenon is weakened,which can effectively reduce or prevent the occurrence of cavitation.In order to solve the problem of restricting high-water-based high-speed radial piston pumps by flow control valves,through theoretical calculation and simulation,the key components of the valve are designed and the structure is optimized.The research results lay a foundation for accelerating the development of high-water-based high-speed radial piston pumps.