Modeling of Flow Pattern over Sacrificial Groin.

Seyed Amir Dastgheib, Alireza Nowroozpour, Mohammad Hossein Niksokhan, M.R.M. Tabatabai

Thursday 2 july 2015

12:15 - 12:30h at Amazon (level 1)

Themes: (T) Water engineering, (ST) River and coastal engineering

Parallel session: 11B. Engineering - River

Groin is a structure constructed at an angle to the flow in order to deflect the flowing water away from unstable banks and limit the erosion. Thus, main functions of groins are protecting bank erosion and maintaining water level by deflecting flow direction. Since the groins may be destroyed by floods and high flows, it can be useful to locate a vertical groin in frontier of main groins for protecting. In addition, the sacrificial groin could be designed for reducing pressure to main Groins. In this paper, flow pattern over sacrificial groin, has been investigated by a numerical model. A numerical modeling of the flow over different length and shapes of sacrificial and main groins has been developed and the results were compared. In this study, by using a numerical model, the capability of sacrificial groin for protecting river banks is indicated. The computational fluid dynamics model which solves the RANS equations coupled to a surface-capturing algorithm to predict the main features of the water flow. The model was developed using the volume of fluid (VOF) method. In this investigation, the RNG model of turbulence with wall functions was used to compute the eddy viscosity. Also, structured hybrid grids were used to accommodate the geometry of the groins. The results of numerical model showed that RNG turbulent model and VOF method for predicting the flow pattern beside groins were suitable. Keywords: River training; Sacrificial Groins; Numerical modeling; Flow Pattern