Numerical simulation of secondary flow around the open and close groins in channel with movable bed

In this research, scouring pattern around open groins with different percentages of opening and close groins is simulated by FLOW3D numerical model using different models of turbulence, and then obtained results from numerical simulation are compared with experimental results. This comparison shows that numerical model is effective for predicting scouring pattern around open groins with different percentages of opening and close groins. Also, among the various turbulence models, the LES turbulence model has the closest results to the experimental results and is selected as the preferred turbulence model. In the following, the power of vortices created around the open groins is checked. Therefore, some criteria were calculated that represent power of cross-flows and were studied the manner of their changes before and after groin in comparison to the extent of opening of groins. The results of this work show that in all cases, cross-flow vortexes that occur because of the groins, continue for a distance equal to the length of groin downstream, and that, the value and power of vortices (Sxy) and vorticity are decreased by moving away from groin, and vortexes and cross-flows are decreased in width of channel with increasing distance from groin. In addition, the value of Sxy and vorticity criteria is decreased by increasing of opening percentage of groin.