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Dynamic analysis of three-dimensional flow in the opening process of a single-disc butterfly valve

Abstract A numerical dynamic analysis is carried out to simulate a three-dimensional flow and to study the performance of a single-disc butterfly valve with a diameter of 1.35 m in the opening process. The unsteady fluid flow during the opening process is studied by using the moving grid technique. The turbulent separated flow is also studied to understand the unsteady flow better through velocity distributions and pressure distributions on the mid-symmetric plane. The formation of vortexes is also discussed. Then the characteristics of butterfly valves such as the flow coefficient, the dynamic torque coefficient, and the drag coefficient are studied. The curves of these characteristics corresponding with the variational valve opening angle are obtained to investigate the performance of the single-disc butterfly valve.