Particle Image Velocimetry measurement of flow around an inclined square cylinder

Abstract This study investigated flow around an inclined square cylinder by using Particle Image Velocimetry technique in a wind tunnel. Two types of inclinations, i.e. forward inclination and backward inclination, were tested. Two inclination angles, i.e. α  = 15° and 30° were tested for each type of inclinations. It was found that the forward inclination enhances the downwash that originally appears behind the upper part of the vertical cylinder, whereas weakens the upwash that is exhibited behind the base part of the vertical cylinder. When the forward inclination angle is large enough, the downwash is enhanced to a downward axial flow, whereas the upwash is completely suppressed. On the contrary, the backward inclination depresses the downwash, while enlarges the upwash. As the backward inclination angle increases, the upwash evolves into an upward axial flow.