Validation of a 1D simplified model of Gironde Estuary based on a database of TELEMACsimulations
Laborie, V.; Hissel, F.; Sergent, P. (2013). Validation of a 1D simplified model of Gironde Estuary based on a database of TELEMACsimulations, in: Kopmann, R. et al. (Ed.) Proceedings of the XXth TELEMAC-MASCARET User Conference, Karlsruhe, Germany, October 16–18, 2013. pp. 77-83
In: Kopmann, R.; Goll, A. (Ed.) (2013). Proceedings of the XXth TELEMAC-MASCARET User Conference, Karlsruhe, Germany, October 16–18, 2013. Bundesanstalt für Wasserbau: Karlsruhe. ISBN 978-3-939230-07-6. VIII, 155 pp., more
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| Authors | | Top |
- Laborie, V.
- Hissel, F., more
- Sergent, P.
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| Abstract |
Within THESEUS European project, on the one hand, an overflowing model of Gironde Estuary, based on TELEMAC software, has been used to create a database of water lines along the estuary depending on a large range of hydrometeorological situations. In this study, no breaching and no modification in the elevation of the dikes were considered in TELEMAC model. This database was then used to validate the construction of a 1D numerical model whose aim is to provide in less than one minute both water heightsand propagation of tide along the Estuary.The model based on TELEMAC-2D was fed by several data sources, a tide signal at Le Verdon and a large range of discharges of the Garonne (at La Réole), the Dordogne (at Pessac), the Dronne (at Coutras) and the Isle (at Libourne). Simulations were led without considering any wind in the Estuary. The tide signal imposed at the mouth of the Estuary, near Le Verdon, was divided into two parts: a sinusoidal signal characterized by its amplitude added to a hydrometeorological surge level. Both amplitudes and surge levels belonged to a large physical range of values. Water levels along the axis of Gironde Estuary were then analyzed with a FFTdecomposition to extract the tide amplitude and phase at eachpoint along the axis and also to obtain the value of mean waterlevels.On the second hand, a permanent 1D shallow water numerical model and a 1D numerical model of tide propagation were obtained developing shallow water equations with the assumption of Gironde Estuary having an exponential increasing width. Its results are mean water depths and tide amplitude along Gironde Estuary from Le Verdon to Ambes. Overflows are supposed to have an influence only on tide amplitudes.Results were compared with TELEMAC database both for mean water levels along Gironde Estuary and tide amplitude. Results for mean water levels along Gironde Estuary show the necessity to complete the equations taken into account. For several hydrometeorological scenarios, the simplified tide amplitude model well represent tide amplitudes along the estuary as overflows occur. |
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