Computational fluid dynamics and experimental analysis on flow rate and torques of a servo direct drive rotary control valve

Abstract

This paper aims to analyze the flow characteristics and fluid torques in a direct drive rotary control valve with a novel structure, and based on the computational fluid dynamics method, the advantages of improved structure are verified. With the establishment of the valve structure and the simulation model, the sliding mesh model and moving region grid are applied to simulate the complete opening and closing process of the valve at dynamic conditions. The results present that the fluid torques generate resistance torques during the increasing process of flow area while providing driving torques in the decreasing period of flow area, which is consistent with the theoretical analysis. In addition, the flow regulation of the fluid chamber is conducted with the computational fluid dynamics method and experimental test, which exhibited disagreement due to the oil leakage phenomenon. The simulation results and experimental results both convince the pressure and flow characteristics, and the improved valve model shows decreased fluid torques of around 17% compared with the original one under the system pressure of 6 MPa.