Assessment of Turbulent Models in Computation of Strongly Curved Open Channel Flows
Subject Areas : Journal of Water Sciences ResearchOmid Seyedashraf 1 , Ali Akbar Akhtari 2
1 - M.Sc. Hydraulics Engineering., Faculty Member, Department of Civil Engineering, Kermanshah University of Technology, Kermanshah, Iran
2 - Assistant Professor, Hydraulics Engineering Faculty Member, Department of Civil Engineering, Razi University, Kermanshah, Iran
Keywords: Open Channel Bend, Strongly Curved Flow, Turbulent Models, Two-phase flow, Volume Of Fluid,
Abstract :
Several rigorous turbulent models have been developed in the past years and it can be seen that more research is needed to reach a better understanding of their generality and precision by verifying their applications for distinct hydraulic phenomena; under certain assumptions. This survey evaluates the performance of Standard k-ε, Realizable k-ε, RNG k-ε, k-ω and RSM models in predicting flow behavior in a strongly curved open channel bend. Accordingly, three-dimensional numerical simulations were carried out using a state-of-the-art computational fluid dynamics code, ANSYS-Fluent14, which employs finite volume method to solve the respective governing equations. The models’ accuracy were analyzed and compared with observed data from experimental studies on a 90° open channel bend. The results indicate that although the RSM model can precisely capture all the flow characteristics in a strongly curved open channel flow, the Standard k-ε model may be considered as slightly less accurate yet much faster model.