PIRENE : Programme intégré de recherche environnement - eau - Partim caractérisation et modélisation hydrauliques des cours d'eau

Report (2004)

Etude des dispositifs de vidange de fond au barrage de l'Ourthe à Nisramont

Report (2004)

Etude sur modèle réduit hydraulique de l'évacuateur de crues du barrage de Pouembout - Projet Koniambo (Nouvelle Calédonie)

Report (2004)

Comparative analysis of the predictive capacity of breaching models for an overtopped rockfill dam

in Proceedings of the International Workshop "Stability and Breaching of Embankment Dams" (2004)

The paper covers a brief description and a comprehensive comparative analysis of several state-of-the-art dam breaching models. The study is specifically focused on the applicability and on the predictive ... [more ▼]

The paper covers a brief description and a comprehensive comparative analysis of several state-of-the-art dam breaching models. The study is specifically focused on the applicability and on the predictive capacity of the models for the gradual breaching of an overtopped rockfill dam. A wide range of modelling techniques is reviewed, from process-oriented numerical simulations to empirical models. Comparisons are performed regarding various aspects, such as the applicability of the model without prior calibration or the possibility of coupling the breaching model with a quasi-3D flow solver such as WOLF. Finally, a sensitivity analysis of the downstream hydrograph to various parameters is conducted and the conclusions drawn are illustrated in the case of a large-scale real application in Belgium. [less ▲]

Large scale 2D numerical modelling of reservoirs sedimentation and flushing operations

in Proceedings of the 9th International Symposium on River Sedimentation (2004)

The quasi-3D flow solver WOLF has been developed at the University of Liege for almost a decade. It has been used to carry out the simulation of silting processes in large reservoirs and to predict the ... [more ▼]

The quasi-3D flow solver WOLF has been developed at the University of Liege for almost a decade. It has been used to carry out the simulation of silting processes in large reservoirs and to predict the efficiency of flushing operations. Besides briefly depicting the mathematical and numerical model, the present paper demonstrates its applicability on the case of a large hydropower project in India. The silting process of the reservoir has been simulated by means of the quasi-3D flow model with a quasi-steady approach. For simulating flushing events, both the topography changes and their interactions with the flow have been carefully handled in a strongly coupled approach. This narrow coupling has required the development of a suitable upwind numerical scheme. Results are presented with 2D- and 3D-views, completed by cross-sections and curves of the variation of key variables. The numerous observations based on those results lead to a global assessment of the silting mechanism and of the flushing efficiency. [less ▲]

Approche unifiée des interactions entre l'hydrodynamique et le milieu naturel ou construit: exemples d'applications expérimentales et numériques

in Actes des 5èmes journées scientifiques et techniques du CETMEF (2004)

Même si le contexte contemporain fait évoluer les problèmes qui y sont liés, force est de constater que les défis majeurs attachés à l’eau subsistent ou se radicalisent. De l'écrêtement des crues au ... [more ▼]

Même si le contexte contemporain fait évoluer les problèmes qui y sont liés, force est de constater que les défis majeurs attachés à l’eau subsistent ou se radicalisent. De l'écrêtement des crues au soutien d'étiage, du recours toujours croissant à l'eau pour l’activité industrielle au sens large au maintien de ses propriétés écologiques pour la consommation, tout concourt à faire du problème de l’eau un défi du 21e siècle, bien rare à épargner et à gérer plus efficacement. Qu'elle s'intéresse à l’origine, à la consommation ou à l’utilisation de l’eau ou encore qu'elle se tourne vers les conséquences possibles des infléchissements que l'homme peut provoquer sur le cycle de l’eau, la gestion actuelle des ressources hydrauliques ne peut plus ignorer les nouvelles potentialités nées de l'accroissement rapide des possibilités numériques qui permettent, avec les acquis théoriques en mécanique des fluides, de développer des outils d'aide à la décision applicables à des situations grandeur nature. Parmi tous les domaines de l’hydraulique touchés par le numérique, l'intérêt du HACH à modéliser l’ensemble des écoulements à surface libre résulte simplement de leur prépondérance dans les phénomènes hydrodynamiques influents sur lesquels on s'efforce d'agir. A l'échelle du système hydrologique global, le souci de gérer, donc d’anticiper les phénomènes naturels et accidentels, conduit ainsi à couvrir avec des approches physiquement basées les différentes étapes que connaît la goutte d’eau lorsqu’elle frappe la surface terrestre, du ruissellement au gonflement des rus, rivières et zones de stockage, jusqu’aux grands fleuves et voies intérieures de navigation. Délaissant volontairement le formalisme des équations utilisées et des méthodes numériques de résolution, cet article s’attache à prouver la pertinence du recours au numérique par une illustration chronologique (au fil de l’eau) de quelques situations réelles gérées par la suite des programmes WOLF, complètement écrits au sein du HACH. [less ▲]

New trends in flood risk analysis: working with 2D flow models, laser DEM and a GIS environment

in Greco, M.; Carravetta, A.; Della Morte, R. (Eds.) Proceedings of the 2nd International Conference on Fluvial Hydraulics: River Flow 2004 (2004)

This paper outlines the integration of new and accurate laser DEM into the determination of floodplains. Global and robust GIS environment is absolutely necessary to manage this very large amounts of ... [more ▼]

This paper outlines the integration of new and accurate laser DEM into the determination of floodplains. Global and robust GIS environment is absolutely necessary to manage this very large amounts of topographic data. The development and interaction of 2D flow models, simplified or not, ensures to offer more accurate and flexible physically based tools to the decision-makers. [less ▲]

Numerical - experimental interaction in hydrodynamics: an integrated approach for the optimal management of hydraulic structures and hydrographic basins

in Lu; Lamas; Li (Eds.) et al Computational Methods in Engineering and Science (2003)

The present paper presents studies and tools devoted to the reduction of uncertain-ties in the scientific knowledge of various unsteady flows, including solid transport effects, in the perspective of ... [more ▼]

The present paper presents studies and tools devoted to the reduction of uncertain-ties in the scientific knowledge of various unsteady flows, including solid transport effects, in the perspective of applications such as restoration, rehabilitation and enhancement of riverbeds, rivers and waterways. This global approach will be tested and fitted in a dynamic and integrated experimental model of reference flows in the laboratory. The relevance of using of physical experimental scale models will be highlighted for the identification of constitutive laws used in numerical modelling. Practical applications prove that the integration of powerful hydrodynamic software for water management is realistic and will lead to compute transient flooding, sedimentation and erosion events in natural compound channels, as well as to design and simulate the behaviour of hydraulic regulation works or locks. It will also help in working out new projects or reconstructions of hydraulic infrastructures, as well as ecological rehabilitations. Even if the sole quantitative plan will be taken into account, this opti-misation project will also lead to highlight favourable solutions, from a qualitative point of view. [less ▲]

Optimising a cascade of hydroelectric power stations with the WOLF package

in Brebbia, C. A. (Ed.) Water Ressources Management (2003)

Original free-surface flow solvers have been developed by the HACH during the last years. The resulting fully integrated WOLF package allows engineers to study a very wide range of free surface flows ... [more ▼]

Original free-surface flow solvers have been developed by the HACH during the last years. The resulting fully integrated WOLF package allows engineers to study a very wide range of free surface flows situations. Successful and accurate computations are performed for phenomena as various as hydrological run-offs and dam breaking in quasi 3 dimensions including solid transport effects, as well as rivers networks modelling with explicit exchanges between river paths. All the models, physically based, use efficient and original numerical methods to solve continuous or discontinuous free-surface flow equations. They handle structured or unstructured grids with both first and second order accurate explicit or implicit algorithms in time and space. WOLF also includes powerful user-friendly pre- and post-processing with 2D and 3D animated visualizations as well as a parameters optimization software interconnected with all the package components and based on the innovating method of genetic algorithms. In this paper, the production of the hydroelectric power plants installed on a 60 km long section of the rivers Amblève and Warche in Belgium is presented in details to illustrate the numerical calculation and optimization process. The river network is modeled using real natural topographic data. Hydrological balance is closed and roughness coefficients are calibrated from water level and discharge field measurements. Hydroelectric production is optimized by an automatic calibration of the parameters of the hydrogram injected in the network from the Robertville dam. This approach leads to a substantial gain in both hydroelectric production and financial benefits and deals with all management and security criteria. [less ▲]

Etudes sur modèle numérique hydraulique du barrage de Kol (Inde)

Report (2003)