NUMERICAL SIMULATION OF VORTEX SHEDDING FROM A CIRCULAR CYLINDER IN THE PRESENCE OF A FREE SURFACE

摘要

CFD simulations of crossflows around a 2-D circular cylinder and the resulting vortex shedding from the cylinder are conducted in the present study. The capability of the CFD solver for vortex shedding simulation from a circular cylinder is validated hi terms of the induced drag and lifting forces and associated Strouhal numbers computations. The validations are done for uniform horizontal fluid flows at various Reynolds numbers in the range 10~3 to 5 x 10~5. Crossflows around the circular cylinder beneath a free surface are also simulated in order to investigate the characteristics of the interaction between vortex shedding and a free surface at Reynolds number 5x10~5. The influence of the presence of the free surface on the vortex shedding due to the cylinder is discussed.