Performance Research Of Digital Large-Flow Emulsion Relief Valve

Emulsion pump station is the power device of the supporting equipment in fully mechanized coal mining face,and the key equipment to realize the safety,high efficiency and high yield of coal mining face.The rapid development of fully mechanized mining technology makes high requests to the supporting quality of emulsion pump station.While at present,the research on the high-pressure and large-flow relief valve used in emulsion pump in imperfect,because of the difference of transmission medium,general relief valve is difficult to meet the requirements of pump station on sensitivity,stability and reliability.As the important control and overload protection element of emulsion pump station,the performance of relief valve is related to the normal operation of emulsion pump station.Focused on the insufficient of the research on emulsion relief valve and considered the special characteristics of emulsion,the structure design and performance analysis of high-pressure and large-flow emulsion relief valve were carried out,and the digital control method was adopted to improve the control precision and working performance of the valve.This study is funded by the science and technology development project of "Research on Testing Technology and Equipment of High-Performance Hydraulic Components of Construction Machinery" of Shandong Province.This paper firstly analyzed the research status of digital relief at home and abroad and proposed the control scheme of digital larger-flow emulsion relief.The size calculation and static characteristic check of the relief valve were carried out according to the design scheme.The mathematical model of the relief valve was established and used to analyze the response and influence factors with Matlab/Simulink software.The hydraulic simulation model of the physical structure of relief valve was established in AMESim platform,and the static and dynamic working characteristics of the relief valve as well as the influence of various structural parameters on the dynamic response were simulated and analyzed,which were used to analyze the influencing factors affecting the working characteristics of the relief valve from the perspective of physical structure.The numerical dynamic simulation of whole internal 3D flow field of the relief valve was carried out based on Pumplinx software.The distribution maps of pressure,speed and turbulence kinetic energy of the internal flow fields of pilot valve,main valve and the whole relief valve were analyzed to study the damage areas by eddy and cavitation under transient and steady state.The comparative simulation and analysis of the influence of key structures on the flow field and dynamic performance were carried out to verify the feasibility of the structure design.Finally,this paper established the simulation work environment of the relief valve based on AMESim and digital control system on Simulink,and carried out the electro-hydraulic joint simulation though the interface between AMESim and Simulink.The simulation result showed that the digital control system can improve the working performance of relief valve,and the developed relief valve can adjust the working pressure according to actual working condition,which can satisfy the design requirement.This paper makes a comprehensive analysis of the digital large-flow emulsion relief valve from the structural design,mathematical model,dynamic characteristics,overall flow field and electro-hydraulic joint control,which provides theoretical support and reference basis for the research on the emulsion relief valve used in the emulsion pump state.