References of "Archambeau, Pierre"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailAssessing the operation rules of a reservoir system based on a detailed modelling chain
Bruwier, Martin ULg; Erpicum, Sébastien ULg; Pirotton, Michel ULg et al

in Natural Hazards & Earth System Sciences (2015), 15

The current operation rules of two muti-purpose reservoirs are analysed based on an integrated model including a hydrological model, a hydraulic model, a model of the reservoir system and a flood damage ... [more ▼]

The current operation rules of two muti-purpose reservoirs are analysed based on an integrated model including a hydrological model, a hydraulic model, a model of the reservoir system and a flood damage model. Five performance indicators have been defined, reflecting the ability to provide drinking water, to control floods, to produce hydropower and to reduce low-flow conditions. Then, impacts of two climate change scenarios are assessed and enhanced operation rules are proposed for mitigation. [less ▲]

Detailed reference viewed: 74 (34 ULg)
Full Text
Peer Reviewed
See detailStochastic modelling of reservoir sedimentation in a semi-arid watershed
Adam, Nicolas; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in Water Resources Management (2015), 29(3), 785-800

Sedimentation in large reservoirs is a major concern in semi-arid regions characterized by severe seasonal water scarcity. As a contribution to improved sediment management, this study analyses the real ... [more ▼]

Sedimentation in large reservoirs is a major concern in semi-arid regions characterized by severe seasonal water scarcity. As a contribution to improved sediment management, this study analyses the real case of the reservoir of Sidi Yacoub in the north of Algeria. First, a dynamic model of the reservoir was set up and used to estimate past water and sediment inflows (period 1990-2010) based on data recorded by the dam operator and measurements at a gauging station located downstream of the reservoir. Second, in a stochastic framework using the statistical characteristics of inflow and outflow discharges, a projection of future sedimentation was performed until 2030, assuming stationarity of the statistical distributions. Third, the model was used to investigate the influence of possible climate change and to quantify the positive effects of soil conservation measures upstream. [less ▲]

Detailed reference viewed: 123 (32 ULg)
Full Text
Peer Reviewed
See detailCan the collapse of a fly ash heap develop into an air-fluidized flow? - Reanalysis of the Jupille accident (1961)
Stilmant, Frédéric ULg; Pirotton, Michel ULg; Archambeau, Pierre ULg 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: 89 (33 ULg)
Full Text
See detailFlood Risk in Liege Area: A Transnational Perspective
Dewals, Benjamin ULg; Archambeau, Pierre ULg; Erpicum, Sébastien ULg et al

in Hydrolink (2015), (3),

Liege is located at the heart of the Meuse basin, which covers parts of France, Belgium, Germany and the Netherlands. Considering explicitly this transnational context when conducting flood risk analysis ... [more ▼]

Liege is located at the heart of the Meuse basin, which covers parts of France, Belgium, Germany and the Netherlands. Considering explicitly this transnational context when conducting flood risk analysis in the area of Liege sheds light on specific features and management opportunities which might otherwise be overlooked. Within a basin-wide collaborative approach, future flood risk was estimated along the course of the Meuse and adaptation measures were evaluated, particularly for the protection of the city of Liege. [less ▲]

Detailed reference viewed: 17 (3 ULg)
Full Text
Peer Reviewed
See detailClosure to “Parapet Wall Effect on Piano Key Weir Efficiency”
Erpicum, Sébastien ULg; Machiels, Olivier; Pirotton, Michel ULg et al

in Journal of Irrigation & Drainage Engineering (2015), 141(1), 07014033

Detailed reference viewed: 36 (3 ULg)
Full Text
Peer Reviewed
See detailPressure and velocity on an ogee spillway crest operating at high head ratio: experimental measurements and instrumentation
Peltier, Yann ULg; Dewals, Benjamin ULg; Archambeau, Pierre ULg et al

in Carvalho, Rita; Pagliara, Stefano (Eds.) 2nd International workshop on hydraulic structures: data validation (2015)

This paper aims at validating pressure and velocity measurements conducted in two physical scale models of an ogee spillway crest operating at heads largely greater than the design head. The design head ... [more ▼]

This paper aims at validating pressure and velocity measurements conducted in two physical scale models of an ogee spillway crest operating at heads largely greater than the design head. The design head of the second model is 50% smaller than the one of the first model. No piles effect or air entrance is considered in the study. The velocity field is measured by Large Scale Particle Image Velocimetry. The relative pressure along the spillway crest is measured using pressure sensors. Comparisons of measured velocities between both spillways indicate low scale effects, the scaled-profiles collapsing in most parts of the flow. By contrast, measurements of relative pressure along the spillway crest differ for large heads. A theoretical velocity profile based on potential flow theory and expressed in a curvilinear reference frame is then fitted to the velocity measurements, considered as reference, for extrapolating the velocity at the spillway crest. Comparing the extrapolated velocity at the spillway crest and the velocity expressed from the relative pressure finally emphasizes that bottom pressure amplitudes are overestimated for the large spillway, while an averaging effect might operate for the pressure measurements on the small spillway. [less ▲]

Detailed reference viewed: 59 (0 ULg)
See detailA modular approach dedicated to dam-break and dam-breaching modelling
Stilmant, Frédéric ULg; Dewals, Benjamin ULg; Erpicum, Sébastien ULg 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: 30 (6 ULg)
Full Text
Peer Reviewed
See detailCan meandering flows in shallow rectangular reservoir be modelled with the 2D shallow water equations?
Peltier, Yann ULg; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in Journal of Hydraulic Engineering (2015)

In this article, the ability of the 2D shallow water equations to model meandering flows in shallow rectangular reservoirs is discussed. Four meandering flows, of various shallowness, were modelled using ... [more ▼]

In this article, the ability of the 2D shallow water equations to model meandering flows in shallow rectangular reservoirs is discussed. Four meandering flows, of various shallowness, were modelled using the academic flow model WOLF 2D, which includes a depth-averaged k- model accounting for the horizontal and vertical turbulent length-scales. The bottom friction was modelled with the Colebrook-White formula and different roughness heights were considered. A Proper Orthogonal Decomposition (POD) was applied to the simulation results to extract the behaviour of the main structures responsible for the meandering flow. The same POD analysis was also performed for the reference experimental flow fields, obtained by Large-Scale Particle Image Velocimetry. The first two POD modes obtained from the numerical simulations assuming a smooth bottom are in good agreement with the experimental modes in terms of energy, as well as temporal and spatial variations, whatever the shallowness. In contrast, the remaining simulated modes are not well rendered. The effect of an increased roughness height in the simulations is finally discussed. It leads to an improved reproduction of the first two modes and of the following modes, except when significant viscous effects govern in the flow. [less ▲]

Detailed reference viewed: 98 (42 ULg)
Full Text
See detailSe barricader : une solution insuffisante face à l'eau
de Muelenaere, Michel; Archambeau, Pierre ULg; Erpicum, Sébastien ULg et al

Article for general public (2014)

Detailed reference viewed: 23 (4 ULg)
Full Text
Peer Reviewed
See detailPrediction of mean and turbulent kinetic energy in rectangular shallow reservoirs
Camnasio, Erica; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in Engineering Applications of Computational Fluid Mechanics (2014), 8(4),

Shallow rectangular reservoirs are common structures in urban hydraulics and river engineering. Despite their simple geometry, complex symmetric and asymmetric flow fields develop in such reservoirs ... [more ▼]

Shallow rectangular reservoirs are common structures in urban hydraulics and river engineering. Despite their simple geometry, complex symmetric and asymmetric flow fields develop in such reservoirs, depending on their expansion ratio and length-to-width ratio. The original contribution of this study is the analysis of the kinetic energy content of the mean flow, based on UVP velocity measurements carried throughout the reservoir in eleven different geometric configurations. A new relationship is derived between the specific mean kinetic energy and the reservoir shape factor. For most considered geometric configurations, leading to four different flow patterns, the experimentally observed flow fields and mean kinetic energy contents are successfully reproduced by an operational numerical model based on the depth-averaged flow equations and a two-length-scale k-e turbulence closure. The analysis also highlights the better performance of this depth-averaged k-e model compared to an algebraic turbulence model. Finally, the turbulent kinetic energy in the reservoir is derived from the experimental measurements and the corresponding numerical predictions based on the k-e model agree satisfactorily in the main jet but not in the recirculation zones. [less ▲]

Detailed reference viewed: 59 (7 ULg)
Full Text
See detailLanduse change and future flood risk: the influence of micro-scale spatial patterns (FloodLand) - 2nd progress report
Dewals, Benjamin ULg; Bruwier, Martin ULg; El Saeid Mustafa, Ahmed Mohamed ULg et al

Report (2014)

The goal of the project FloodLand is to investigate the complex interactions between landuse change and future flood risk. Landuse change is assumed to be mainly driven by population growth and socio ... [more ▼]

The goal of the project FloodLand is to investigate the complex interactions between landuse change and future flood risk. Landuse change is assumed to be mainly driven by population growth and socio-economic factors. It affects future flood risk by altering catchment hydrology as well as vulnerability in the floodplains; but the feedback effect of (the perception of) changes in flood hazard on landuse evolution is also considered. The research is based on a chain of modelling tools, which represent parts of the natural and human systems, including: landuse change modelling, transportation modelling as an onset for the estimation of indirect flood damage, continuous hydrological modelling (forced by precipitation and temperature data disturbed according to climate change scenarios), as well as efficient hydraulic modelling of inundation flow in the floodplains. Besides reproducing a broad spectrum of processes, the modelling approach spans over multiple scales, from the regional or catchment level down to the floodplain and building levels. This distinctive feature is reflected both within the individual models and through their combination involving fine-scale detailed analyses (or data) embedded within coarser models at a broader level. [less ▲]

Detailed reference viewed: 99 (44 ULg)
Full Text
Peer Reviewed
See detailVelocity and turbulence measurements for assessing the stability of riverbeds: a comparison between UVP and ADVP
Duma, Diana ULg; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in 11th International Conference on Hydroscience & Engineering - "Hydro-Engineering for Environmental Challenges" (2014, October)

Maintaining the overall stability of active riverbeds requires a deep understanding of the complex interactions between turbulent flow forces and forces stabilizing the riverbed. Standard approaches do ... [more ▼]

Maintaining the overall stability of active riverbeds requires a deep understanding of the complex interactions between turbulent flow forces and forces stabilizing the riverbed. Standard approaches do not properly take into account the turbulence fluctuations in non-uniform flows, while these are of primary importance in the mechanisms determining the stability of stones. In a new approach, the flow forces are quantified by means of parameters combining explicitly the velocity and turbulence distributions over a certain water depth above the riverbed. In this paper, as an onset for using these newly developed bed stability parameters, we report on new experimental measurements of velocity and turbulent kinetic energy based on acoustic methods, whereas all previous uses at the new bed stability parameters relied on Laser PIV Techniques. For quasi-uniform and non-uniform flow conditions, velocity measurements were conducted with two complementary devices: an ultrasonic velocimeter probe (UVP) and an acoustic Doppler velocimeter profiler (ADVP). The results are compared and discussed in detail. A general consistency between the two types of measurements is obtained, while some discrepancies are highlighted close to the bed and tentative explanations are given. [less ▲]

Detailed reference viewed: 63 (12 ULg)
Full Text
Peer Reviewed
See detailFlow and turbulence characterization as an onset for assessing the stability of gravel beds
Duma, Diana ULg; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in 7th International Conference on Fluvial Hydraulics (2014, September)

The flow characteristics, such as velocity profiles and turbulence intensities, are of high practical relevance in the assessment of riverbed stability. So far, the Shields diagram remains the most widely ... [more ▼]

The flow characteristics, such as velocity profiles and turbulence intensities, are of high practical relevance in the assessment of riverbed stability. So far, the Shields diagram remains the most widely accepted approach for defining the initiation of sediment motion. However, it faces a number of shortcomings. In principle, it is only valid for uniform flow conditions and, under non-uniform flow conditions, it fails to account properly for the influence of turbulence in sediment entrainment. In this paper, we focus on a more detailed description of quasi-uniform and non-uniform flow characteristics in the vicinity of the critical flow conditions for inception of motion of gravel beds. Laboratory experiments were designed, involving two configurations. First, the entire bottom of the flume was paved with stones of uniform diameter (8 or 15 mm), leading to quasi-uniform flow conditions. Second, the flume bottom was smooth upstream of the zone of measurement while the downstream part was covered with gravels, leading to a sudden smooth-to-rough transition. The flow velocity was obtained by acoustic measurements and the turbulence intensity was calculated for both configurations. By fitting the velocity profile to a modified logarithmic law, the shear velocity was estimated. Standard approaches for predicting the threshold of motion, initially developed for uniform flows, were compared to other methods, based on depth-averaged turbulence kinetic energy, recently proposed in literature for non-uniform flow conditions. [less ▲]

Detailed reference viewed: 73 (6 ULg)
Full Text
See detailTowards enhanced estimates of future water demand in the Meuse basin: literature review
De Cuyper, Anaïs; Bruwier, Martin ULg; Archambeau, Pierre ULg et al

Report (2014)

With respect to water management in the Meuse basin, the hydrological consequences of climate change have been taken into account in several studies so far; but this is not the case of many other ... [more ▼]

With respect to water management in the Meuse basin, the hydrological consequences of climate change have been taken into account in several studies so far; but this is not the case of many other environmental and socio-economic changes, including trends in future water demand. The objective of this report is to serve as an onset for the development of a first approach to estimate at a relatively large-scale future water demand in the Meuse basin. Based on a review of recent literature, this report discusses the key drivers which influence water demand, with the aim of identifying the most suitable methods to implement in a subsequence more detailed analysis, as well as to highlight the data needs. [less ▲]

Detailed reference viewed: 39 (14 ULg)
Full Text
See detailLa Meuse au fil des crues
Devuyst, Paul; Dewals, Benjamin ULg; Archambeau, Pierre ULg et al

Article for general public (2014)

Detailed reference viewed: 26 (6 ULg)
Full Text
See detailComparison between Experimental and SPH Models over a Sharp-crested Weir
Lodomez, Maurine ULg; Erpicum, Sébastien ULg; Dewals, Benjamin ULg et al

Scientific conference (2014, August 28)

In this paper the numerical simulations of a free surface flow over a sharp-crested weir are presented and compared to experimental results. The numerical model implemented consists of the meshless ... [more ▼]

In this paper the numerical simulations of a free surface flow over a sharp-crested weir are presented and compared to experimental results. The numerical model implemented consists of the meshless Smoothed Particle Hydrodynamics (SPH) method which uses Navier-Stokes equations and the Tait equation of state for water. This numerical method has been developed in the framework of a master thesis and aimed to define the characteristics of the free jet. The validation of the results was performed through the analysis of the pressure field and the comparison of the numerical free surface profiles with experimental measurements conducted in the Hydraulic Laboratory of the University of Liège (ULg). A good qualitative agreement has been obtained. [less ▲]

Detailed reference viewed: 40 (14 ULg)