Application of volume of fluid (VOF) method in conjunction with shear stress transport (SST) k-ω turbulence closure model to investigate spillway flow

Bayrakdar, Fatih
Hydraulic engineers often require to assess the reasons and consequences of interaction of flow with structures. Computational Fluid Dynamics (CFD) became a useful tool in this regard in recent years as it provides ample amount of information both on flow and its interaction with its surrounding. To this end, flows over a spillway are investigated. The computational domain for the flow over a spillway is based on the study by Dargahi (2006). Numerical results are compared to previous experimental ones. In the study, SST k-ω Model is considered for turbulence closure. The free surface of these flows is simulated using Volume of Fluid (VOF) approach. The effect of spillway roughness, scale of the model, and the downstream conditions are discussed for a single spillway structure. The scale effects have shown that cavitation related studies should be carried using prototype scales in numerical simulation of spillway flows. If the roughness is accounted only as a constant in governing equations in Reynolds-Averaged-Navier-Stokes (RANS) simulations, current study shows that its effect may not be captured pronouncedly. Downstream conditions imposed in the model could produce simple hydraulic jump conditions. In these cases, air-entrainment due to jump is calculated based on aerated fluid volume. 


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Citation Formats
F. Bayrakdar, “Application of volume of fluid (VOF) method in conjunction with shear stress transport (SST) k-ω turbulence closure model to investigate spillway flow,” M.S. - Master of Science, Middle East Technical University, 2017.