Numerical Simulation of Vortex Shedding on Cylinders of Different Configuration at Moderate to High Reynolds Number

This research work, presents the results of numerical investigation of vortex formation and vortex shedding phenomenon on differently shaped cylinders, i.e. triangular, square and elliptical are presented for Reynolds number in the turbulent range. An analysis from the obtained pressure, velocity vector and turbulent kinetic energy contours and the values of CD, CL and St number shows a significant influence of the geometrical configuration of the body and Reynolds number when fluid flows over it. The pressure and velocity vector contours give a very clear presentation of the effect of differently shaped bodies by highlighting the region of high and low pressures and high and low velocity regions in the fluid, respectively. Also, the turbulent kinetic energy contours show the areas with high and low TKE. It has also been observed that for a triangular object the overall increment in the drag coefficient as Reynolds number increases from 103 to 106, while the overall decrement for elliptical cylinder is 23.40% and 76.81%, respectively. As for the CL versus Reynolds number it can be seen that it decreases with the rise in Reynolds number for all the three cases. It has also been observed that for the triangular and square cylinder the value of St number remains almost same as the Reynolds number grows from 103 to 106. However, for elliptical cylinder the St number slightly increases as the Reynolds number transitions from 103 to 104 and then further decreases as the Reynolds number reaches 106.