A STUDY ON LENGTH AND THE MAXIMUM WIDTH OF THE CIRCULATING REGION CAUSED BY A DIKE

摘要

Based on 2-D depth averaged water flow differential equations and using some assumptions different from those made by other researchers on turbulent viscous shear stress, the lateral distribution of main flow velocity, and turbulent viscous coefficient, the formulas used to compute circulating flow length and the maximum circulating width are derived in this paper. The results are in reasonable agreement with experimental data. The research results indicate that the circulating flow length varies with the dike length, depth, roughness, area contraction ratio and river width contraction ratio, and the maximum circulating width varies with the river width, area contraction ratio and river width contraction ratio. The width contraction ratio equals to the area contraction ratio only for rectangular channel, and they are different from each other for natural river.