Application of a high-resolution scheme in simulation of flow in curved channel using boundary-fitted curvilinear coordinates

This paper demonstrates the effectiveness of a high-resolution numerical scheme in boundary- fitted curvilinear coordinates for simulation of flow at channel bends. Two-dimensional shallow water equations, which are transformed from physical domain to computational domain, are solved by a robust high-resolution scheme particularly developed for boundary-fitted curvilinear coordinates. Finite-volume method is adopted for discretization of governing equations in computational domain. Turbulence shear stresses are included in the model by eddy-viscosity approach. Moreover, the effect of secondary flow, which is significant in channel bends, has been included in the model and the results have been compared with the results achieved by neglecting this phenomenon. Secondary flow intensity is evaluated by an analytical approach; the deviation of bed shear stress from main flow is related to secondary flow intensity and is considered in the model as well. All numerical results are compared with experimental data and they show satisfactory agreement.