Flow Field Characteristics and Structure Improvement of Double-stage Safety Valve

The paper proposes a new double-stage large flow protection relief valve based on the double-stage linkage structure, to solve the problem that when it is impacted by the top plate, the traditional hydraulic support protective relief valve has smaller overflow and lower sensitivity, which causes the column circuit to be damaged. The flow field characteristics of double-stage protective relief valve are numerically simulated by the computational fluid dynamics method and semi-implicit connection pressure equation calculation model. Then the dynamic characteristics of the flow field distribution of the double-stage protective relief valve are obtained. According to the law of fluid flow, the structure of main valve core is optimized for the negative pressure, cavitation and vortex area. The flow field characteristics of the optimized double-stage protection valve are simulated and analyzed. In the end, the flow field characteristics of optimized double-stage protective relief valve are compared with the original. The results show that the negative pressure value of double-stage protective relief valve is reduced by 15%, and the outlet velocity of double-stage protective relief valve is reduced by 21% compared to the unoptimized when the main core is fully opened. The research results provide reference for the evolution design of high-flow, impact-resistant hydraulic support safety valve structure.