Bed Topography in a 180° Converging or Diverging Bend Using SSIIM Numerical Model

The effect of convergence and divergence ratios of cross sections along a river in a bend of 180° on the changes to bed topography was investigated using an SSIIM model. The results indicated that the changes in convergence and divergence ratios in the channel bend significantly affected the scour depth and sedimentation height. With the increase in the convergence ratio, the deepest scour and highest sedimentation values increased by 4.7 and 2.25 times, respectively, compared to those in the uniform bend. Also, by increasing the divergence ratio, the deepest scour depth and highest sedimentation values decreased by 1.9 and 8 times, respectively, compared to those in the uniform bend.