Physical and Numerical Modeling of Flow in Heterogeneous Roughness Non-Prismatic Compound Open Channel

Differences in the flow properties in the main channel and flood plains causes, mass and momentum tensions between the both sections. The non-prismatic compound open channel cross section intensifies the mass and momentum transferring between the main channel and floodplains and has significant effect on the flow properties through the compound open channel. In this study the flow properties in the heterogeneous Roughness Non-Prismatic Compound Open Channel was assessed using the numerical and physical modeling. The physical modeling was conducted in the hydraulic laboratory center of Tehran University and numerical modeling was carried out using the Flow-3D as famous computation fluid dynamic tool (CFD).The results indicates that the Flow-3D is an effective tool for modeling the flow in the heterogeneous roughness non-prismatic compound open channel. During the CFD modeling it was found that the RNG turbulence model is more precise for simulation and modeling the flow properties. The results show that the heterogeneous roughness has significant effect on the flow characteristics such as velocity distribution and share stress gradient.