An Investigation of the Water Flow Past the Butterfly Valve

This paper presents a numerical simulation of flow past the butterfly valve using Commercial Fluid Dynamics software FLUENT. In static analysis, the positions of the disk were set to be 0 degrees (completely opened), 30 degrees, 45 degrees, 60 degrees and 75 degrees under 1, 2 and 3 m/s water speed. The angular velocities were set to be 0.039 and 1.57 rad/s under 1 m/s water speed in dynamic analysis. The study focuses on the investigation of the characteristic of loss coefficient and torque behavior of the 150 mm and 300 mm in diameter butterfly valves. From the results obtained, it was found that the loss coefficient and torque increased when the disk angle was increased. By increasing the water speed, the loss coefficient remained constant while the torque increased. In dynamic analysis of both angular speeds, the maximum torque occurred at 70 degrees -80 degrees in closing turn and 100 degrees -110 degrees in opening turn. The experiment was also carried out to verify the numerical results. By comparing between the experimental and numerical results, it was found that the loss coefficients and torques obtained from these methods were similar.