Abstract: By use of the large-eddy simulation, numerical solutions of two-dimensional backward-step separation flows in open channels are obtained. The behavior in different regions for step-induced separation flow and statistical characteristics for fluctuation pressure on the wall within the reattachment zone is investigated. The results obtained are compared with the experimental values. A weakly compressible flow model and a non-uniform grid are used in this paper. The calculated results show that the method of t...