This study presents the two-dimensional numerical simulations of a flow around a rotating cylinder at Re = 3900 using standard k-e turbulence model. The two-dimensional incompressible Navier-stokes equations are solved using OpenFoam. Hydrodynamic coefficients and vortex shedding patterns for flow around cylinder are studied. The predicted responses are in good agreement with the published literature. The transverse, streamwise, grid size and time steps have significant effect on the wake formation and hydrodynamic coefficients. These investigations are helpful for better understanding the flow around the circular cylinders and improve the structural designs. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2021.