Numerical Study on the Suppression of the Oscillating Wake of a Square Cylinder by a Traveling Wave Wall

作者：Xu, Wei; Zhang, Li-Qi; Xu, Feng^*

来源：International Journal of Computational Methods in Engineering Science and Mechanics, 2019, 20(1): 48-63.

DOI：10.1080/15502287.2018.1538269

• Flow around a square cylinder
• Lift and drag coefficients
• Low Reynolds number
• Square cylinders
• Traveling wave
• Unsteady numerical analysis
• Vortex shedding frequency
• Vortex-shedding modes

Traveling waves generated on the side surfaces of a square cylinder are employed to suppress the oscillating wake for improving the flow behavior around a square cylinder;this method is termed the traveling wave wall (TWW) method. This study aimed to evaluate the influence of the key parameters of TWW on the control of aerodynamic forces and the oscillating wake of the flow around a square cylinder. Unsteady numerical analyses at a low Reynolds number (Re) of 100 were performed using a two-dimensional CFD simulation. First, the grid independence and time step independence tests of the simulation were conducted to verify the rationality of the solving parameter settings, and the validation of flow around the fixed square cylinder at Re =100 was carried out. Subsequently, the lift and drag coefficients and the vortex shedding modes under different combinations of three TWW control parameters, including wave velocity, wave amplitude, and wavenumber, were analyzed in detail. The results show that TWW can remarkably reduce the mean value of drag coefficient and the RMS value of the lift coefficient by more than 12% compared to the method involving a standard square cylinder. Two peaks occur in the lift coefficient spectrum, with the low frequency corresponding to the vortex shedding frequency in the wake of the flow around the square cylinder and the high frequency corresponding to the traveling wave frequency. The vorticity contours show that the alternating vortices in the wake of the square cylinder are not completely suppressed under the selected control parameters.

• 出版日期2019-1-2
• 单位华南理工大学