Spanwise length effects on three-dimensional modelling of flow over a circular cylinder

Abstract

In this study, both the two-dimensional (2-D) and three-dimensional (3-D) vortex shedding flows around a circular cylinder are solved using a finite difference method. Numerical experiments are carried out to investigate the spanwise length effects on the prediction of global parameters and the near-wake flow field. The calculated Reynolds number is 1000. The results indicate clearly that the 2-D simulation gives inaccurate predictions at the present Reynolds number. The predictions are significantly improved in 3-D simulations, but inaccuracies may also occur if the spanwise length is set too small. Good agreement with experimental data can be achieved with spanwise lengths above twice the cylinder diameters.