Author(s): Benjamin Abban; Neil Armitage

Linked Author(s): Neil Armitage

Keywords: Local Scour; Rivers; Movability Number; CFD; FLUENT 6. 2

Abstract: Local scour around bridge piers in rivers is a major cause of failure. Unfortunately, it is hard to accurately predict. The Movability Number approach offers an alternative numerical solution – at least for clear water scour. An “equilibrium model”, in which the bed was successively modified in response to computed “scour potentials” until an equilibrium scour hole resulted, was developed within the commercial CFD code FLUENT 6. 2. Bed deformation and mesh adaptation functions were written to perform the bed modifications and ensure the integrity of the domain mesh as the bed geometry changed. The performance of the standard k-model was compared with the RSM model, and standard wall functions with non-equilibrium wall functions. The results of the numerical simulations were then compared to physical model data. Preliminary investigations indicate that the Movability Number approach may serve as a good alternative to other numerical models for the prediction of local scour holes in the case of clear water scour.

DOI:

Year: 2007