Hydrodynamic and morphodynamic sensitivity of a river’s main channel to groyne geometry

ABSTRACT

As is widely known, the groyne layout affects the three-dimensional flow situation and sediment budget in groyne fields. Lack of knowledge exists concerning the evolution of hydrodynamics and morphodynamics in the main channel of rivers due to distinct groyne layouts. Accordingly, the sensitivity of the stream flow and the river bed in the fairway to groyne geometry were investigated with the help of a three-dimensional hydrodynamic model and a sediment transport model by considering eight variants and seven discharges in a straight reach of the River Danube. The variation of crest elevation and length indicated highest sensitivity, especially at modelled discharges for which the largest geometrical changes due to the modification of the groyne layout were implemented. Within a curved reach larger effects for length variation and smaller ones for the variation of crest elevation were found. These findings can be incorporated into future research and planning of groyne layouts.

Keywords:

• Field studies
• RANS models
• river training structures
• sediment transport
• streams and rivers
• three-dimensional models

Acknowledgements

The authors thank the river authority Viadonau for their logistic support contributing to the study and A. McWilliams for improving the English.

ORCID

Martin Glas http://orcid.org/0000-0003-4564-2907

Kurt Glock http://orcid.org/0000-0003-4143-7893

Michael Tritthart http://orcid.org/0000-0002-7821-3300