Abstract
On the basis of laboratory experiments, this chapter presents the effect of different dune dimensions on flow separation. The present research assesses the quality of Reynolds-averaged Navier–Stokes turbulence model for predicting the flow over two-dimensional dunes. Three different dunes were developed with two lee-slope angles of 8° (Δ = 4&6 cm) and 38° (Δ = 4&8 cm). The length of the simulated separation zone was compared with experimental data. It is found that the numerical model provides a good overall consistency with the ADV measurements. Also the separation zone has a strong relation with the lee angle. At lee angles less than 10°, the shape of the crest or dune height has no effective impact on flow separation.
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Acknowledgments
The first author is grateful to Prof. Gerald Zenz for his kind support of this research in the Institute of Hydraulic Engineering and Water Resource Management, Graz university of Technology, Austria.
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Motamedi, A., Afzalimehr, H., Zenz, G., Galoie, M., Motamedi, A. (2014). Rans Simulations of Flow Over Dunes with Low Lee and Sharp Lee Angles. In: Gourbesville, P., Cunge, J., Caignaert, G. (eds) Advances in Hydroinformatics. Springer Hydrogeology. Springer, Singapore. https://doi.org/10.1007/978-981-4451-42-0_42
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DOI: https://doi.org/10.1007/978-981-4451-42-0_42
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