The effects of perforated cylinders on the vortex shedding on the suppression of a circular cylinder Engin Pinar, Tahir Durhasan, Göktürk M. Ozkan, Muhammed M. Aksoy, Huseyin Akilli and Besir Sahin EPJ Web Conf., 143 (2017) 02094 Published online: 12 May 2017 DOI: 10.1051/epjconf/201714302094