| Numerical Simulation of Vortex
Shedding from an Oscillating Circular Cylinder
Universidade de São Paulo
Abstract The interaction between cylinder oscillation and the shedding of vortices is investigated numerically in this talk. The near wake structure is presented for different values of reduced velocity of a cylinder free to oscillate transversally. One of the objectives of this work is to compare the numerical results with experimental data obtained in the water tank facility of IPT, University of Sao Paulo. The attraction of applying numerical methods to this problem is that the way the flow is modified can be studied in closer detail. In the computer it is possible to investigate many different flow conditions more easily. The method used for the simulation is based on the vortex-in-cell formulation incorporating viscous diffusion. The Navier-Stokes equations are solved using the operator-splitting technique, where convection and diffusion of vorticity are treated serparately. The convection part is modelled assuming that the vorticity field is carried on a large number of discrete vortices. Force coefficients are calculated by considering the normal gradient of vorticity at the wall to evaluate the pressure contribution and the vorticity at the wall to obtain the skin friction. |