Abstract
The non-linear k-ε model is applied to 3-D computation of unsteady flows around a square cylinder in open channels. Applicability of the non-linear k-ε model to the Karman vortices in the 2-D flow field is firstly investigated through the comparison of calculated results with experimental ones conducted in the closed water section by Lyn and the model constants are adjusted. Then, the 3-D computations of unsteady flows around a square cylinder in open channels are carried out focusing on the Karman vortices and the horseshoe vortices generated in the upstream region of a cylinder. The effects of the depth to the 3-D flow structures are also investigated through the comparison of the numerical results under the conditions of the different depths.
