Flow control for vortex shedding of a circular cylinder based on a steady suction method

Abstract

In this study, a suction flow control method was employed to suppress the vortex shedding of a circular cylinder based on a multi-point suction type. A digital particle image velocimetry (PIV) system was used to conduct detailed flow field measurements under different suction flow control conditions with simultaneously measuring the pressure distribution on the test models. Five steady suction flow rates of 20, 40, 60, 80, and 95 L/min were employed in the testing. The suction control effects were investigated under an angle of 90.0° of the suction holes; the effects of the suction flow control along the axial direction of the test model were investigated. The mean and fluctuating pressure coefficients, the lift and drag coefficients, the mean velocity fields of the circular cylinder, and the mean velocity profiles in the wake under the suction flow control were then analyzed. The results indicated that the steady suctions exhibited excellent control effects and could dramatically reduce the fluctuations of lift coefficients and the averages of the drag coefficients and distinctly suppress the alternating vortex shedding (changing into symmetric mode). The control effects of the suction along the axial direction of the model are not uniform and the control effects are improved from the section without suction to the suction section.