Experimental Study on Wake Flow of an Inclined Square Cylinder

This study aims to examine the validity of the independence principle (IP) and the vortex characteristics for a square cylinder with different inclination angles (á) encountering wind flow at Reynolds number (Re) of about 3600. A 1D vorticity probe was used to measure the spanwise vorticity component in a wind tunnel, together with a reference Xprobe located at the edge of the wake to provide a reference signal. By examining the contours of velocity and vorticity components using the phase-averaged method, the dependence of the flow properties on inclination angles was analyzed. The present results show that the three-dimensionality of the wake is enhanced and the vortex shedding strength is weakened with the increase of the cylinder inclination angle. When á is larger than 40°, the IP is no longer valid. The Strouhal number (St_N), obtained using the velocity component normal to the cylinder axis, remains approximately a constant within the experimental uncertainty when á is smaller than about 30°, indicating the validity of the IP over this angle range.