Abstract

Treatments of irregular boundary, bed deformation and free surface are main problems in 3-D flow and sediment model. Based on control equations of turbulent flow considering irregular boundary from liquid-solid two phase flow theory, the model and the Wall Function are adopted to develop a new model. In the model, apart from model and the Wall Function, VOF method and the porosity concept are adopted to simulate water surface, irregular boundary and bed deformation. In sediment transport simulation, non-equilibrium bed load transport equation is adopted in this model. Using the new model, flow field, changing of water level, and local scour-deposition around spur dike are simulated. At the same time, PIV instrument was adopted to measure the flow field around spur-dike. Computed result is compared with experimental data. The model developed can successfully simulate the separating structure of flow and circumfluence around the spur dike, secondary flow in the circumfluence area, scour hole profile and bed contours and agree well with the experimental data.

Keywords: 3-D turbulent model, spur dike, sediment transport, VOF method, the porosity, wall function