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Impacts of climate change on future flood damage on the river Meuse, with a distributed uncertainty analysis ; Stilmant, Frédéric ; Dewals, Benjamin et al in Natural Hazards (2015), 77(3), 1533-1549 Flood-risk assessments are an objective and quantitative basis for implementing harmonized flood mitigation policies at the basin scale. However, the generated results are subject to different sources of ... [more ▼] Flood-risk assessments are an objective and quantitative basis for implementing harmonized flood mitigation policies at the basin scale. However, the generated results are subject to different sources of uncertainty arising from underlying assumptions, data availability and the random nature of the phenomenon. These sources of uncertainty are likely to bias conclusions because they are irregularly distributed in space. Therefore, this paper addresses the question of the influence of local features on the expected annual damage in different municipalities. Based on results generated in the frame of a transnational flood-risk-assessment project for the river Meuse (Western Europe) taking climate change into account, the paper presents an analysis of the relative contributions of different sources of uncertainty within one single administrative region (the Walloon region in Belgium, i.e. a river reach of approximately 150 km). The main sources of uncertainty are not only found to vary both from one municipality to the other and in time, but also to induce opposite effects on the computed damage. Nevertheless, practical conclusions for policy-makers can still be drawn. [less ▲] Detailed reference viewed: 244 (51 ULg)Conduite optimisée de la Romanche : Détermination du lâcher d'alerte au barrage de Livet (phase 2) Stilmant, Frédéric ; Erpicum, Sébastien ; Archambeau, Pierre et al Report (2015) Detailed reference viewed: 22 (1 ULg)Contribution to real-time inundation mapping in the Walloon region Stilmant, Frédéric ; Pirotton, Michel ; Goffin, Louis et al Conference (2015, April 02) Detailed reference viewed: 30 (7 ULg)Can the collapse of a fly ash heap develop into an air-fluidized flow? - Reanalysis of the Jupille accident (1961) Stilmant, Frédéric ; Pirotton, Michel ; Archambeau, Pierre et al in Geomorphology (2015), 228 A fly ash heap collapse occurred in Jupille (Liege, Belgium) in 1961. The subsequent flow of fly ash reached a surprisingly long runout and had catastrophic consequences. Its unprecedented degree of ... [more ▼] A fly ash heap collapse occurred in Jupille (Liege, Belgium) in 1961. The subsequent flow of fly ash reached a surprisingly long runout and had catastrophic consequences. Its unprecedented degree of fluidization attracted scientific attention. As drillings and direct observations revealed no water-saturated zone at the base of the deposits, scientists assumed an air-fluidization mechanism, which appeared consistent with the properties of the material. In this paper, the air-fluidization assumption is tested based on two-dimensional numerical simulations. The numerical model has been developed so as to focus on the most prominent processes governing the flow, with parameters constrained by their physical interpretation. Results are compared to accurate field observations and are presented for different stages in the model enhancement, so as to provide a base for a discussion of the relative influence of pore pressure dissipation and pore pressure generation. These results show that the apparently high diffusion coefficient that characterizes the dissipation of air pore pressures is in fact sufficiently low for an important degree of fluidization to be maintained during a flow of hundreds of meters. [less ▲] Detailed reference viewed: 83 (33 ULg)A modular approach dedicated to dam-break and dam-breaching modelling Stilmant, Frédéric ; Dewals, Benjamin ; Erpicum, Sébastien et al in Advances in Hydroinformatics (2015) The paper presents an integrated tool for dam-break hazard modelling. It is based on a two-dimensional, depth-averaged hydraulic model that uses a conservative and shock-capturing finite volume scheme on ... [more ▼] The paper presents an integrated tool for dam-break hazard modelling. It is based on a two-dimensional, depth-averaged hydraulic model that uses a conservative and shock-capturing finite volume scheme on a Cartesian grid. The hydraulic model is designed so that different zones within the computation domain can be modelled with different spatial resolutions and/or different model enhancements (e.g. pressurised flows, sediment transport, etc.). The two-dimensional model can be coupled with lumped models that compute the water stage in reservoirs and the outflow discharge through hydraulic structures, in case of normal operating, failure of a valve or breaching processes. These features make hydraulic modelling versatile and computationally efficient. They enable the definition of different failure scenarios, which is of prominent importance given the uncertainty of such a phenomenon. If several hydraulic structures are involved, the procedure takes the behaviour of each structure into account. The sensitivity of the results with respect to the interactions between the flow and the terrain (roughness coefficient, collapse of buildings, breaching process) can be analysed. The results of the hydraulic model are handled thanks to a graphical user interface that provides one-, two- and three-dimensional views and animations of the unsteady flow-field and enables the understanding and verification of the results. Danger maps are generated based on the results of one or more ‘worst-case’ scenarios. In case of a complete risk analysis, the danger maps are combined with data on the exposure and vulnerability of elements at risk for the computation of the corresponding damage. [less ▲] Detailed reference viewed: 29 (6 ULg)Conduite optimisée de la Romanche : Modèle cinématique Stilmant, Frédéric ; Pirotton, Michel ; Dewals, Benjamin Report (2014) Detailed reference viewed: 12 (3 ULg)Etude d'impact sur les inondations en cas de non retrait d'une centrale hydroélectrique amovible sur la Basse-Sambre Stilmant, Frédéric ; Pirotton, Michel ; Archambeau, Pierre Report (2014) Detailed reference viewed: 35 (6 ULg)Conduite optimisée de la Romanche : détermination du lâcher d’alerte au barrage de Livet (phase 1) Stilmant, Frédéric ; Erpicum, Sébastien ; Archambeau, Pierre et al Report (2013) Detailed reference viewed: 25 (5 ULg)Hydraulic modelling of the river Meuse Dewals, Benjamin ; ; Stilmant, Frédéric et al Conference (2013, September) Detailed reference viewed: 19 (3 ULg)Dike-break induced flows: a simplified model Stilmant, Frédéric ; Pirotton, Michel ; Archambeau, Pierre et al in Environmental Fluid Mechanics (2013), 13(1), 89-100 A simplified model for the prediction of the steady-state outflowthrough a breach in an inland dike is presented. It consists in the application of the mass and momentum conservation principles to a ... [more ▼] A simplified model for the prediction of the steady-state outflowthrough a breach in an inland dike is presented. It consists in the application of the mass and momentum conservation principles to a macroscopic control volume. A proper definition of the shape of the control volume enables to take the main characteristics of the flow into account and thus to compensate for the extreme simplification of the spatial representation of the model. At the breach, a relation derived from the shallow-water equations is used to determine the direction of the flow. Developments have been guided by numerical simulations and results have been compared to experimental data. Both the accuracy and the domain of validity of the simplified model are found satisfactory. [less ▲] Detailed reference viewed: 90 (26 ULg)Etude hydraulique d'une lagune artificielle sur l'île de Corisco Stilmant, Frédéric ; Archambeau, Pierre ; Pirotton, Michel Report (2013) Detailed reference viewed: 45 (4 ULg)Evaluation of flood protection measures for the city of Liege considering climate change Stilmant, Frédéric ; Archambeau, Pierre ; Dewals, Benjamin et al Report (2013) Detailed reference viewed: 28 (7 ULg)Depth-averaged flow modeling in curvilinear coordinates Stilmant, Frédéric ; Egan, Raphael ; Archambeau, Pierre et al Conference (2013) A set of depth-averaged equations in curvilinear coordinates is presented. This extension of the standard shallow water equations to curved flows and to jet flows leads to a model which is very versatile ... [more ▼] A set of depth-averaged equations in curvilinear coordinates is presented. This extension of the standard shallow water equations to curved flows and to jet flows leads to a model which is very versatile. Its applicability and precision is assessed by the computation of a discharge coefficient and the nappe profiles for a sharp crested weir. Results confirm the relevance of the approach. Even if not taken into consideration in the set of equations presented here, a discussion shows that head losses could be included in the model so as to extend its application field to many civil and environmental engineering applications. [less ▲] Detailed reference viewed: 88 (34 ULg)Etude des écoulements induits par une déstabilisation du terril de la Héna Stilmant, Frédéric ; Pirotton, Michel ; Dewals, Benjamin et al Report (2012) Detailed reference viewed: 85 (11 ULg)Dike-break induced flows: a simplified model Stilmant, Frédéric ; Dewals, Benjamin ; Archambeau, Pierre et al Conference (2011, November) A simplified model for the prediction of the steady-state outflow through a breach in an inland dike is presented. It consists in the application of the mass and momentum conservation principles to a ... [more ▼] A simplified model for the prediction of the steady-state outflow through a breach in an inland dike is presented. It consists in the application of the mass and momentum conservation principles to a macroscopic control volume. A proper definition of the shape of the control volume enables to take into account the main characteristics of the flow and thus to compensate for the extreme simplification of the space discretisation of the model. At the breach, a relation derived from the shallow-water equations is used to determine the directions of the flow. Developments have been guided by numerical simulations and results have been compared to experimental data. Both the precision and the application domain of the simplified model are found satisfactory. [less ▲] Detailed reference viewed: 22 (5 ULg) |
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