APPLICATION OF LARGE-EDDY SIMULATION TO AN OSCILLATING FLOW PAST A CIRCULAR-CYLINDER

Three-dimensional sinusoidally oscillating flows around a circular cyl inder are investigated by using a viscous flow method (VFM) and a larg e eddy simulation (LES). A second-order accurate in time fractional st ep method and a combined finite-difference/spectral approximation are employed to solve the filtered incompressible Navier-Stokes equations. To demonstrate the viability and accuracy of the method, we calculate two cases of steady approach flows at Reynolds numbers Re = 100 using VFM and Re = 10(4) using LES. For sinusoidally oscillating flows at b eta = 1035, the flow is 2D for KC < 0.5, 3D for 0.5 < KC < 2, and turb ulent for KC > 2. For KC = 0.5, 0.8 and 1, the flow is calculated usin g VFM. For KC = 2, 3, 4, 5, 8 and 10, we have simulated the flow using LES with the Smagorinsky subgrid scale model. The drag and inertia co efficients are calculated from the in-line force acting on the cylinde r and are in very good agreement with experimental data.