Two-dimensional Numerical Analysis on the Flow and Turbulence Structures in Artificial Dunes

Optimal Strategy to Tackle a 2D Numerical Analysis of Non-Uniform Flow over Artificial Dune Regions: A Comparison with Bibliography Experimental Results

“…However, the velocity profiles of the k-ω SST modeling results are in better agreement than those of k-ε modeling results near the bottom and the separation zone from x = 0 m to x = 0.3 m. The TKE values are defined by the mean value of kinetic energy related to the turbulence, and results of both models showed remarkable trends of turbulent intensity along the dune crest line. Numerical results of the k-ω SST model were slightly better than those of k-ε modeling overall, as analyzed by previous researches [23]. Thus, the k-ε model had a limit of not being suitable for simulating the flow in the vicinity of the channel bottom, because the model was developed for models with large Reynolds numbers to solve the flow with relatively higher turbulent regions.…”

“…The flow properties in the experiments were measured in single parts of the dunes. The results of the experiments were used to validate numerous numerical researches [22,23,36,47]. One of the experimental cases [6] was selected to evaluate the numerical calculation in this study.…”

“…A considerable disadvantage is the scale effect. Therefore, numerical simulation is widely applied because it minimizes the scaling effects and facilities [18][19][20][21][22][23][24][25]. Although adequate results can be obtained with this approach, there are many limitations owing to the combination of complex properties of the turbulent flow.…”

“…In this study, we used the turbulence model based on the RANS equations to simulate the numerical modeling for turbulence flow over a fixed dune, and to reduce the computational time by solving the mean velocity and effects of the temporal fluctuation. Numerous numerical studies have provided reasonable results for turbulent flow on sandy dunes using various RANS models [2,23,[30][31][32][33][34][35][36]. Considering the previous studies, we selected k-ε and k-ω shear-stress transport (SST) turbulence models from the RANS models.…”

“…The physical experimental data of dune profiles and conditions were obtained from the previous research [6]; these data have been widely used and proven to be accurate in previous studies [2,23,32,35,36,47,48]. We employed the OpenFOAM (The OpenFOAM Foundation Ltd. London, United Kingdom) toolbox, an open-source CFD platform based on a cell-centered finite volume method.…”