Effect of attack angle on the flow around adjacent circular and rectangular prisms


Niğde Ömer Halisdemir Üniversitesi Mühendislik Bilimleri Dergisi, vol.10, no.2, pp.833-839, 2021 (Peer-Reviewed Journal) identifier


An experimental investigation has been carried out to clarify the flow structure around adjacent circular and rectangular prisms. The measurements of hot-wire for Re= 4.1 x 103, 9.0 x 103 and 1.5 x 104, lift and drag force for Re = 1.0 x 104, and in addition the flow visualization experiments for Re = 2.3 x 103 have been performed in the range of 0°    180°. The adjacent bodies consist of a circular cylinder having 9.5 mm diameter and a rectangular prism having 6 mm x 10 mm cross-section attached to the circular cylinder from its short side in all the cases. The hot wire measurement results showed that the Strouhal number has Reynolds number independence for Re = 4.1x103, 9.0x103, and 1.5x104. Sudden peaks in St and lift coefficients are obtained for a similar reason that is reattachment of the separated shear layer in the vicinity of  = 60 and 174. For the adjacent bodies compared with the bare circular cylinder, 40%, and 25% drag reduction is obtained at  = 0 and 174, respectively. The obtained results show that the variations of lift coefficient, drag coefficient, and Strouhal number are strictly subjected to the attack angle.