Numerical Simulation of Two-Dimensional Laminar Flow around Circular Cylinder with Splitter Plate

In order to study the effect of splitter plate on flows past through a circular cylinder, the finite volume method, unstructured grids, and the laminar flow model were used to solve the two-dimensional incompressible N-S equation. A thin plate was placed along the horizontal centerline downstream of the circular cylinder, and the flow past this circular cylinder was simulated with a two-dimensional model at Reynolds number 200. The change in the contour of instantaneous velocity, Strouhal number, and the average drag coefficient with the plate length were then obtained. Numerical results indicate that the splitter plate can effectively suppress the vortex shedding of the cylinder, weaken the energy dissipation in the wake region, and reduce the Strouhal number. The vortices are confined to the sides of the plate stably and symmetrically, and the vortex shedding behind the circular cylinder disappear completely when the length of the splitter plate is seven times more than the diameter of the circular cylinder (i.e., L/D≥7), then the flow field behind the circular cylinder changes into streamlines. Meanwhile, the drag coefficient continuously decreases along with the plate length. When the plate length is seven times the cylinder diameter, the drag coefficient decreases from 1.43 to 0.87, by about 40%.