Daniel Caviedes-Voullième

Forschungszentrum Jülich · Institute of Bio- and Geosciences (IBG)

This paper presents a Godunov-type numerical formulation that is local, conservative and scalable in both accuracy and resolution. The keystone of the framework is to recast a local multi-resolution discontinuous Galerkin formulation and, combine it with multiwavelets (MWDG) to adaptively decide local resolution level by manipulating multiwavelet c...

Avalanches, debris flows and other types of gravity-driven granular flows are a common hazard in mountainous regions. These regions often have human settlements in the lower parts of valleys, with human structures dangerously exposed to the destructive effects of these geophysical flows. Therefore a scientific effort has been made to understand, mo...

Recognizing the leap in high-performance computing with accelerated co-processors, we propose a lightweight approach to adapt legacy codes to next generation hardware and achieve efficiently a high degree of performance portability. We focus on abstracting the computing kernels at the loop levels based on the lightweight, preprocessor-based embedde...

An accurate assessment of the physical states of the Earth system is an essential component of many scientific, societal and economical considerations. These assessments are becoming an increasingly challenging computational task since we aim to resolve models with high resolutions in space and time, to consider complex coupled partial differential...

The Simulation EnviRonment for Geomorphology, Hydrodynamics, and Ecohydrology in Integrated form (SERGHEI) is a multi-dimensional, multi-domain, and multi-physics model framework for environmental and landscape simulation, designed with an outlook towards Earth system modelling. At the core of SERGHEI's innovation is its performance-portable high-p...

Rainfall is a spatiotemporally variated process and one of the key elements to accurately capture both catchment runoff response and floodplain extents. Flash floods are the result of intense rainfall, typically associated to highly variable rain in both space and time, such as convective storms. In this work, the extent within-storm variability af...

The Simulation Environment for Geomorphology, Hydrodynamics and Ecohydrology in Integrated form (SERGHEI) is a multi-dimensional, multi-domain and multi-physics model framework for environmental and landscape simulation, designed with an outlook towards Earth System Modelling. It aims to provide a modelling environment for hydrodynamics, ecohydrolo...

Rainfall is a spatiotemporally varied process and key to accurately capturing catchment runoff and determining flood response. Flash flood response of a catchment can be strongly governed by a rainfall’s spatiotemporal variability and is influenced by storm movement which drives a continuous spatiotemporal change throughout a rainfall event. In thi...

Rainfall is a complex, spatial and temporally variated process and one of the core inputs for hydrological and hydrodynamic modelling. Most rainfalls are known to be moving storms with varying directions and velocities. Storm movement is known to be an important influence on runoff generation, both affecting peak discharge and the shape of hydrogra...

Rainfall is a complex, spatial and temporally variated process and one of the core inputs for hydrological and hydrodynamic modelling. Most rainfalls are known to be moving storms with varying directions and velocities. Storm movement is known to be an important influence on runoff generation, both affecting peak discharge and the shape of hydrogra...

Hydrological (dis)connectivity, in the sense of surface and subsurface runoff (dis)connectivity, emerges from the formation of spatial flow patterns across scales. As such, hydrological connectivity can not be directly measured, but often manifests itself in observable hydrological signatures, such as hydrographs and water balance. These signatures...

Microtopography is the small scale deviation of Earth's topography, such as humps and depressions. The hydrological literature agrees that the presence of microtopography can affect infiltration patterns by creating local pressure head differences that drive water into the soil at increased or decreased rates. Runoff generation is a non-linear proc...

Microtopography (MT) can govern runoff dynamics as a net result of local heterogeneities in the flow paths and ponding. This in turn controls the development of the surface water layer that connects and flows downslope. It is therefore important to understand which microtopographic features affect runoff generation dynamics and its macroscopic—hill...

Editorial of the Special Issue "Computational advances and innovations in flood risk mapping" on Journal of Flood Risk Management

Microtopography is recognised as one of the morphological features which controls runoff generation, surface hydrodynamics, and surface runoff hydrological response. The spatial scales of microtopography are orders of magnitude smaller than typical hydrological domains such as hillslopes or catchments. The hydrodynamic response in the presence of m...

A wavelet-based local mesh refinement (wLMR) strategy is designed to generate multiresolution and unstructured triangular meshes from real digital elevation model (DEM) data, for efficient hydrological simulations at catchment-scale. The wLMR strategy is studied considering slope-and curvature-based refinement criteria to analyze DEM inputs: the sl...

In Gerhard et al. (2015a) a new class of adaptive Discontinuous Galerkin schemes has been introduced for shallow water equations, including the particular necessary properties, such as well-balancing and wetting-drying treatments. The adaptivity strategy is based on multiresolution analysis using multiwavelets in order to encode information across...

The multiscale nature of ecohydrological processes and feedbacks implies that vegetation patterns arising in water‐limited systems are directly linked to water redistribution processes occurring at much shorter time scales than vegetation growth. This in turn suggests that the initially available water in the system can play a role in determining t...

Rainfall-runoff simulations are increasingly being performed with physically-based and spatially distributed solvers. The current computational and numerical technology enables the use of full shallow water equations solvers to be applied for these type of flow problems. Nonetheless, Zero-Inertia (diffusive wave) solvers have been historically favo...

The high computational cost of large-scale, process-based hydrological simulations can be approached using variable resolution meshes, where only the region around significant topographic features is refined. However, generating quality variable resolution meshes from digital elevation data is non-trivial. In literature, usually a slope or curvatur...

Runoff generation from rainfall events is a complex, spatial and temporally dependent process strongly governed, among other factors, by catchment surface topography. Although it is widely known that many catchments experience morphological evolution, it is often ignored in analysis for different reasons ranging from simplification to lack of data....

Hydraulic phenomena in open-channel flows are usually described by means of the shallow water equations. This hyperbolic non-linear system can be used for predictive purposes provided that initial and boundary conditions are supplied and the roughness coefficient is calibrated. When calibration is required to fully pose the problem, several strateg...

In the past decade, shallow water solvers have dramatically improved both in terms of accuracy and computational power. New mathematical models and numerical schemes have been systematically verified against 1D exact solutions and laboratory experiments. Despite the two-dimensional nature of some of these benchmark tests, none of them reports compl...

The measurement and simulation of 2D free-surface shallow flows is carried out in this work. For the experimental study a 3D-sensing device (Microsoft Kinect) is used to measure both steady and transient water surface elevation fields with different flow characteristics. This procedure provides 640x480 px resolution water surface level point clouds...

Surface flows of hydrological interest, including overland flow, runoff, river and channel flow and flooding have received significant attention from modellers in the past 30 years. A growing effort to address these complex environmental problems is in place in the scientific community. Researchers have studied and favoured a ple-thora of technique...

The artificial catchment “Hühnerwasser” was built in a post-mining landscape, as a field experiment to observe and monitor early-development ecosystems at hillslope scale. Early on, rain-induced rill and channels formation was observed, followed by vegetation growth in between rills, and later on inside the rills. In this work, we aim to describe t...

Numerical modeling of bed-load transport in shallow flows, particularly oriented toward environmental flows, is an active field of research. Nevertheless, other possible applications exist. In particular, bed-load transport phenomena are relevant in urban drainage systems, including sewers. However, few applications of coupled two-dimensional (2D)...

In this work steady and unsteady free-surface flows are investigated by means of open channel experiments and finite volume simulations. In a first laboratory stage, a RGB-D sensor was employed to measure transient water surface elevation fields with different flow characteristics. In the second part, 2D finite volume simulations were applied to th...

Microtopographic features, although minute relative to the hillslope scales, are not insignificant in terms of runoff generation and rain-runoff-infiltration partitioning and overall hillslope hydrological signals. Assessing the effects of such small scale features, arguably requires mathematical models that can cope with microtopographic complexit...

Plant-plant biotic interactions are important for the functioning of semi-arid ecosystems. Interference goes beyond competition for resources, and it can involve chemical interactions (i.e. allelopathy) that influence the net interaction outcome. The output of a competitive interaction for a limited resource could change whenever allelopathic plant...

Landslides are an ubiquitous natural hazard, and therefore human infrastructure and settlements are often at risk in mountainous regions. In order to better understand and predict landslides, systematic studies of the phenomena need to be undertaken. In particular, computational tools which allow for analysis of field problems require to be thoroug...

One of the most difficult issues in the development of hydrologic models is to find a rigorous source of data and specific parameters to a given problem, on a given location that enable reliable calibration. In this paper, a distributed and physically based model (2D Shallow Water Equations) is used for surface flow and runoff calculations in combi...

Numerical modelling of wide ranges of different physical scales, which are involved in Shallow Water (SW) problems, has been a key challenge in computational hydraulics. Adaptive meshing techniques have been commonly coupled with numerical methods in an attempt to address this challenge. The combination of MultiWavelets (MW) with the Runge-Kutta Di...

Hydraulic phenomena in open-channel flows are usually described by means of the shallow water equations. This hyperbolic non-linear system can be used for predictive purposes provided that initial and boundary conditions are supplied and the roughness coefficient is calibrated. When calibration is required to fully pose the problem, several strateg...

We provide an adaptive strategy for solving shallow water equations with dynamic grid adaptation including a sparse representation of the bottom topography. A challenge in computing approximate solutions to the shallow water equations including wetting and drying is to achieve the positivity of the water height and the well-balancing of the approxi...

This paper presents the formulation of an adaptive finite volume (FV) model for the shallow water equations. A Godunov-type reformulation combining the Haar wavelet is achieved to enable solution-driven resolution adaptivity (both coarsening and refinement) by depending on the wavelet's threshold value. The ability to properly model irregular topog...

The finite volume Godunov-type method has extensively been used to simulate shallow water flows. It has been widely applied to simulate real-scale floods due to its features such as locality and conservation properties. [1-3] However, shallow flows present a wide range of varying spatial scales, for which mesh adaptation may be an optimal solution...

Transient granular flow can be solved assuming that the dynamics are well described under the hypothesis of shallow equations including complex rheology terms. For this purpose a Roe type first order scheme on 2D meshes is employed. Particular attention is devoted to the numerical discretization of fluxes and source terms which are based in the Rie...

Landslides are an ubiquitous natural hazard, and therefore human infrastructure and settlements are often at risk in mountainous regions. In order to better understand and predict landslides, systematic studies of the phenomena need to be undertaken. In particular, computational tools which allow for analysis of field problems require to be thoroug...

Some environmental, irrigation and engineering applications have a special interest in the accurate simulation of 3D subsurface flows. The Richards equation is the physical model most used for singlephase, isothermal, variably saturated flow. It is a non-linear partial differential equation requiring numerical solutions which can be computationally...

The accurate numerical simulation of river flow by means of 2D shallow-water model requires a large amount of topographic data to build a sufficiently accurate Digital Terrain Model (DTM). The DTM must fully cover the possible flooded area as well as the main channel (or channels) of the river. It is common to find DTM's for large floodplains gener...

Numerical simulation is a useful tool for understanding and predicting floodplain system hydrodynamics, a key aspect within hydrological systems. Accurate modeling of groundwater-surface water interactions in floodplains is of special importance not only to properly quantify mass transfer from groundwater to surface water and vice versa, but specia...

Richards equation is a non-linear partial differential equation that describes flow in porous media. To solve it, numerical methods that need to be conservative, stable, accurate and efficient, are required. Finite volume methods have not been reported as widely as finite difference or finite element methods. This work is focused on providing numer...

Exfiltration and infiltration phenomena are an important part of nutrient cycling, and therefore, groundwater interactions with the dry surface or the surface water flow are of importance. Numerical simulation is a useful tool for understanding and predicting floodplain system hydrodynamics. Consequently, accurate modeling of groundwater-surface wa...

Hydrological simulation of rain-runoff processes is often performed with lumped models which rely on calibration to generate storm hydrographs and study catchment response to rain. In this paper, a distributed, physically-based numerical model is used for runoff simulation in a mountain catchment. This approach offers two advantages. The first is t...

Hydrological simulation of rain-runoff processes is often performed with lumped, empirical models dependent on calibration to generate storm hydrographs and study catchment response to storms. However, it is possible to make use of 2D shallow-water models to perform distributed, physically-based runoff analysis at the catchment scale. This approach...

A method that solves both groundwater and surface domains by means of modeling physical processes is presented. Numerically, the submodels are an explicit 2D finite volume shallow-water equations solver and an implicit 3D finite volume Richards equation solver. To link the submodels a non-iterative external coupling algorithm is used. The integrate...