Numerical investigation of coherent structures forming around bridge piers sitting on an inclined surface

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2021-11

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Hesap, Emre

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Coherent structures forming around the piers play an important role in the formation of scour hole. Detached Eddy Simulation is used in this study to investigate the three-dimensional coherent structures forming around bridge piers which sit on an inclined surface. Initiation of the scour process at flat bed conditions is investigated within the current study. Two cases are investigated one with the lower Reynolds number case which is typical for flume experiments whereas the larger Reynolds number case represents the physical conditions found in nature. Also, comparison was done with a study in the literature with uninclined bed conditions. It was observed that a horseshoe vortex forms around the pier in both cases studied. Shear stress values over the bed is evaluated. As result, it was observed that high bed shear stress values occur in the acceleration regions on both sides of the pier and along the detached shear layers. In both simulations, these stresses are observed to be effective across a wider band on the shallow channel side rather than on the deep channel side. Comparing the results of this study with the literature it was concluded that inclined channels are more critical in terms of the scour formation.

Subject Keywords

Detached Eddy Simulation, Coherent Structures, Bridge Pier

URI

https://hdl.handle.net/11511/94638

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

E. Hesap, “Numerical investigation of coherent structures forming around bridge piers sitting on an inclined surface,” M.S. - Master of Science, Middle East Technical University, 2021.