Simulation of laminar vortex shedding flow past cylinders using a coupled BEM and FEM model Original Research Article

This paper describes a novel computational model developed to simulate laminar vortex-shedding flows past circular cylinders in 2D incompressible viscous flows in external flow fields. The model based on unsteady 2D Navier–Stokes equations in primitive variables is able to solve the infinite boundary value problems by extracting the boundary effects on a specified finite computational domain, using the projection method. The external flow field is simulated using the boundary element method (BEM) by solving a pressure Poisson equation that assumes the pressure as zero at the infinite boundary. The momentum equation of the flow motion is solved using the three-step finite element method (FEM). The present model is applied to simulate vortex-shedding flow past a single circular cylinder and flow past two cylinders in which one act as a control cylinder, for low Reynolds number flows. For both the cases, the time development of the flow towards periodic vortex shedding, are illustrated by streamline pictures. The simulation results are compared with experimental data and other numerical models and found to be very reasonable and satisfactory.