Numerical and expermental investigation of flow downstream of perforated cylinder at low reynolds number

The aim of present study is to investigate the effects of deployment of perforated cylinder on vortex street suppression and flow structure on downstream of a circular cylinder in deep water and at low Reynolds numbers by using numerical simulations along with the technique of high-image-density Particle Image Velocimetry (PIV), in this purpose, during the sudies, porosity of perforated cylinder and diameters of cylinders were kept constant. This study carried out with the related to six diffrent of Reynolds numbers between750 to 2000 for PIV study and ten various value of Reynolds number is considered from range of 150 to 2000 for CFD analysis.For validation purposes, numerical investigations were run for solid cylinder cases to achieve agreement between the simulations and the experimental results as a case study. Furthermore, numerical simulations were performed to see the effect of placing the perforated cylinder around the solid cylinder, concentrically. In this regards, Velocity and vorticity contours, turbulent kinetic energy, and streamline topologies were investigated in the wake region in order to reveal the differences in flow structuers of circular cylinder among various distance rates at different Reynolds numbers. As a conclusion, According to the results, suppression of Karman vortex street is receivable with utilize of perforated cylinder around single cylinder. At all Re numbers according to the both numerical and expermental results, after perforated cylinder was concentrically placed with respect to the circular cylinder was obvioused a reduction approximately 20% to 45% in Drag coefficient.