Among all aspects of geosciences, we mainly focus on gravity driven flows arising in many situations such as
hazardous flows (flooding, rogue waves, landslides...),
sustainable energies (hydrodynamics-biology coupling, biofuel production, marine energies...),
risk management and land-use planning (morphodynamic evolutions, early warning systems...)
There exists a strong demand from scientists and engineers in fluid mechanics for models and numerical tools able to simulate not only the water depth and the velocity field but also the distribution and evolution of external quantities such as pollutants or biological species and the interaction between flows and structures (seashores, erosion processes...). The key point of the researches carried out within ANGE is to answer this demand by the development of efficient, robust and validated models and numerical tools.
Due to the variety of applications with a wide range of spatial scales, reduced-size models like the shallow water equations are generally required. From the modelling point of view, the main issue is to describe the behaviour of the flow with a reduced-size model taking into account several physical processes such as non-hydrostatic terms, biological species evolution, topography and structure interactions within the flow. The mathematical analysis of the resulting model do not enter the field of hyperbolic equations anymore and new strategies have to be proposed. Moreover, efficient numerical resolutions of reduced-size models require particular attention due to the different time scales of the processes and in order to recover physical properties such as positivity, conservativity, entropy dissipation and equilibria.
The models can remain subject to uncertainties that originate from incomplete description of the physical processes and from uncertain parameters. Further development of the models may rely on the assimilation of observational data and the uncertainty quantification of the resulting analyses or forecasts.
The research activities carried out within the ANGE team strongly couple the development of methodological tools with applications to real–life problems and the transfer of numerical codes. The main purpose is to obtain new models adapted to the physical phenomena at stake, identify the main properties that reflect the physical meaning of the models (uniqueness, conservativity, entropy dissipation, ...), propose effective numerical methods to approximate their solution in complex configurations (multi-dimensional, unstructured meshes, well-balanced, ...) and to assess the results with data in the purpose of potentially correcting the models.
The difficulties arising in gravity driven flow studies are threefold.
Models and equations encountered in fluid mechanics (typically the free surface Navier-Stokes equations) are complex to analyze and solve.
The underlying phenomena often take place over large domains with very heterogeneous length scales (size of the domain, mean depth, wave length, ...) and distinct time scales, e.g. coastal erosion, propagation of a tsunami, ...
These problems are multi-physics with strong couplings and nonlinearities.
Hazardous flows are complex physical phenomena that can hardly be represented by shallow water type systems of partial differential equations (PDEs). In this domain, the research program is devoted to the derivation and analysis of reduced complexity models compared to the Navier-Stokes equations, but relaxing the shallow water assumptions. The main purpose is then to obtain models well-adapted to the physical phenomena at stake.
Even if the resulting models do not strictly belong to the family of hyperbolic systems, they exhibit hyperbolic features: the analysis and discretisation techniques we intend to develop have connections with those used for hyperbolic conservation laws. It is worth noticing that the need for robust and efficient numerical procedures is reinforced by the smallness of dissipative effects in geophysical models which therefore generate singular solutions and instabilities.
On the one hand, the derivation of the Saint-Venant system from the Navier-Stokes equations is based on two approximations (the so-called shallow water assumptions), namely
the horisontal fluid velocity is well approximated by its mean value along the vertical direction,
the pressure is hydrostatic or equivalently the vertical acceleration of the fluid can be neglected compared to the gravitational effects.
As a consequence the objective is to get rid of these two assumptions, one after the other, in order to obtain models accurately approximating the incompressible Euler or Navier-Stokes equations.
On the other hand, many applications require the coupling with non-hydrodynamic equations, as in the case of micro-algae production or erosion processes. These new equations comprise non-hyperbolic features and a special analysis is needed.
As for the first shallow water assumption, multi-layer systems were proposed to describe the flow as a superposition of Saint-Venant type systems , , . Even if this approach has provided interesting results, layers are considered separate and non-miscible fluids, which implies strong limitations. That is why we proposed a slightly different approach , based on a Galerkin type decomposition along the vertical axis of all variables and leading, both for the model and its discretisation, to more accurate results.
A kinetic representation of our multilayer model allows to derive robust numerical schemes endowed with crucial properties such as: consistency, conservativity, positivity, preservation of equilibria, ... It is one of the major achievements of the team but it needs to be analyzed and extended in several directions namely:
The convergence of the multilayer system towards the hydrostatic Euler system as the number of layers goes to infinity is a critical point. It is not fully satisfactory to have only formal estimates of the convergence and sharp estimates would provide an optimal number of layers.
The introduction of several source terms due for instance to the Coriolis force or extra terms from changes of coordinates seems necessary. Their inclusion should lead to substantial modifications of the numerical scheme.
Its hyperbolicity has not yet been proven and conversely the possible loss of hyperbolicity cannot be characterised. Similarly, the hyperbolic feature is essential in the propagation and generation of waves.
The hydrostatic assumption consists in neglecting the vertical acceleration of the fluid. It is considered valid for a large class of geophysical flows but is restrictive in various situations where the dispersive effects (like wave propagation) cannot be neglected. For instance, when a wave reaches the coast, bathymetry variations give a vertical acceleration to the fluid that strongly modifies the wave characteristics and especially its height.
Processing an asymptotic expansion (w.r.t. the aspect ratio for shallow water flows) into the Navier-Stokes equations, we obtain at the leading order the Saint-Venant system. Going one step further leads to a vertically averaged version of the Euler/Navier-Stokes equations involving some non-hydrostatic terms. This model has several advantages:
it admits an energy balance law (that is not the case for most dispersive models available in the literature),
it reduces to the Saint-Venant system when the non-hydrostatic pressure term vanishes,
it consists in a set of conservation laws with source terms,
it does not contain high order derivatives.
The coupling of hydrodynamic equations with other equations in order to model interactions between complex systems represents an important part of the team research. More precisely, three multi-physics systems are investigated. More details about the industrial impact of these studies are presented in the following section.
To estimate the risk for infrastructures in coastal zones or close to a river, the resolution of the shallow water equations with moving bathymetry is necessary. The first step consisted in the study of an additional equation largely used in engineering science: The Exner equation. The analysis enabled to exhibit drawbacks of the coupled model such as the lack of energy conservation or the strong variations of the solution from small perturbations. A new formulation is proposed to avoid these drawbacks. The new model consists in a coupling between conservation laws and an elliptic equation, like the Euler/Poisson system, suggesting to use well-known strategies for the analysis and the numerical resolution. In addition, the new formulation is derived from classical complex rheology models and allowed physical phenomena like threshold laws.
Interaction between flows and floating structures is the challenge at the scale of the shallow water equations. This study requires a better understanding of the energy exchanges between the flow and the structure. The mathematical model of floating structures is very hard to solve numerically due to the non-penetration condition at the interface between the flow and the structure. It leads to infinite potential wave speeds that could not be solved with classical free surface numerical schemes. A relaxation model was derived to overcome this difficulty. It represents the interaction with the floating structure with a free surface model-type.
If the interactions between hydrodynamics and biology phenomena are known through laboratory experiments, it is more difficult to predict the evolution, especially for the biological quantities, in a real and heterogeneous system. The objective is to model and reproduce the hydrodynamics modifications due to forcing term variations (in time and space). We are typically interested in phenomena such as eutrophication, development of harmful bacteria (cyanobacteria) and upwelling phenomena.
In environmental applications, the most accurate numerical models remain subject to uncertainties that originate from their parameters and shortcomings in their physical formulations. It is often desirable to quantify the resulting uncertainties in a model forecast. The propagation of the uncertainties may require the generation of ensembles of simulations that ideally sample from the probability density function of the forecast variables. Classical approaches rely on multiple models and on Monte Carlo simulations. The applied perturbations need to be calibrated for the ensemble of simulations to properly sample the uncertainties. Calibrations involve ensemble scores that compare the consistency between the ensemble simulations and the observational data. The computational requirements are so high that designing fast surrogate models or metamodels is often required.
In order to reduce the uncertainties, the fixed or mobile observations of various origins and accuracies can be merged with the simulation results. The uncertainties in the observations and their representativeness also need to be quantified in the process. The assimilation strategy can be formulated in terms of state estimation or parameter estimation (also called inverse modelling). Different algorithms are employed for static and dynamic models, for analyses and forecasts. A challenging question lies in the optimization of the observational network for the assimilation to be the most efficient at a given observational cost.
The main challenge in the study of the non-hydrostatic model is to design a robust and efficient numerical scheme endowed with properties such as: positivity, wet/dry interfaces treatment, consistency. It must be noticed that even if the non-hydrostatic model looks like an extension of the Saint-Venant system, most of the known techniques used in the hydrostatic case are not efficient as we recover strong difficulties encountered in incompressible fluid mechanics due to the extra pressure term. These difficulties are reinforced by the absence of viscous/dissipative terms.
In the quest for a better balance between accuracy and efficiency, a strategy consists in the adaptation of models. Indeed, the systems of partial differential equations we consider result from a hierarchy of simplifying assumptions. However, some of these hypotheses may turn out to be irrelevant locally. The adaptation of models thus consists in determining areas where a simplified model (e.g. shallow water type) is valid and where it is not. In the latter case, we may go back to the “parent” model (e.g. Euler) in the corresponding area. This implies to know how to handle the coupling between the aforementioned models from both theoretical and numerical points of view. In particular, the numerical treatment of transmission conditions is a key point. It requires the estimation of characteristic values (Riemann invariant) which have to be determined according to the regime (torrential or fluvial).
Hydrodynamic models comprise advection and sources terms. The conservation of the balance between source terms, typically viscosity and friction, has a significant impact since the overall flow is generally a perturbation around an equilibrium. The design of numerical schemes able to preserve such balances is a challenge from both theoretical and industrial points of view. The concept of Asymptotic-Preserving (AP) methods is of great interest in order to overcome these issues.
Another difficulty occurs when a term, typically related to the pressure, becomes very large compared to the order of magnitude of the velocity. At this regime, namely the so-called low Froude (shallow water) or low Mach (Euler) regimes, the difference between the speed of the gravity waves and the physical velocity makes classical numerical schemes inefficient: firstly because of the error of truncation which is inversely proportional to the small parameters, secondly because of the time step governed by the largest speed of the gravity wave. AP methods made a breakthrough in the numerical resolution of asymptotic perturbations of partial-differential equations concerning the first point. The second one can be fixed using partially implicit scheme.
Coupling problems also arise within the fluid when it contains pollutants, density variations or biological species. For most situations, the interactions are small enough to use a splitting strategy and the classical numerical scheme for each sub-model, whether it be hydrodynamic or non-hydrodynamic.
The sediment transport raises interesting issues from a numerical aspect. This is an example of coupling between the flow and another phenomenon, namely the deformation of the bottom of the basin that can be carried out either by bed load where the sediment has its own velocity or suspended load in which the particles are mostly driven by the flow. This phenomenon involves different time scales and nonlinear retroactions; hence the need for accurate mechanical models and very robust numerical methods. In collaboration with industrial partners (EDF–LNHE), the team already works on the improvement of numerical methods for existing (mostly empirical) models but our aim is also to propose new (quite) simple models that contain important features and satisfy some basic mechanical requirements. The extension of our 3D models to the transport of weighted particles can also be here of great interest.
Numerical simulations are a very useful tool for the design of new processes, for instance in renewable energy or water decontamination. The optimisation of the process according to a well-defined objective such as the production of energy or the evaluation of a pollutant concentration is the logical upcoming challenge in order to propose competitive solutions in industrial context. First of all, the set of parameters that have a significant impact on the result and on which we can act in practice is identified. Then the optimal parameters can be obtained using the numerical codes produced by the team to estimate the performance for a given set of parameters with an additional loop such as gradient descent or Monte Carlo method. The optimisation is used in practice to determine the best profile for turbine pales, the best location for water turbine implantation, in particular for a farm.
Sustainable development and environment preservation have a growing importance and scientists have to address difficult issues such as: management of water resources, renewable energy production, bio/geo-chemistry of oceans, resilience of society w.r.t. hazardous flows, urban pollutions, ...
As mentioned above, the main issue is to propose models of reduced complexity, suitable for scientific computing and endowed with stability properties (continuous and/or discrete). In addition, models and their numerical approximations have to be confronted with experimental data, as analytical solutions are hardly accessible for these problems/models. A. Mangeney (IPGP) and N. Goutal (EDF) may provide useful data.
Reduced models like the shallow water equations are particularly well-adapted to the modelling of geophysical flows since there are characterized by large time or/and space scales. For long time simulations, the preservation of equilibria is essential as global solutions are a perturbation around them. The analysis and the numerical preservation of non-trivial equilibria, more precisely when the velocity does not vanish, are still a challenge. In the fields of oceanography and meteorology, the numerical preservation of the so-called geostrophic state, which is the balance between the gravity field and the Coriolis force, can significantly improve the forecasts. In addition, data assimilation is required to improve the simulations and correct the dissipative effect of the numerical scheme.
The sediment transport modelling is of major interest in terms of applications, in particular to estimate the sustainability of facilities with silt or scour, such as canals and bridges. Dredging or filling-up operations are expensive and generally not efficient in the long term. The objective is to determine a configuration almost stable for the facilities. In addition, it is also important to determine the impact of major events like emptying dam which is aimed at evacuating the sediments in the dam reservoir and requires a large discharge. However, the downstream impact should be measured in terms of turbidity, river morphology and flood.
It is a violent, sudden and destructive flow. Between 1996 and 2005, nearly 80% of natural disasters in the world have meteorological or hydrological origines. The main interest of their study is to predict the areas in which they may occur most probably and to prevent damages by means of suitable amenities. In France, floods are the most recurring natural disasters and produce the worst damages. For example, it can be a cause or a consequence of a dam break. The large surface they cover and the long period they can last require the use of reduced models like the shallow water equations. In urban areas, the flow can be largely impacted by the debris, in particular cars, and this requires fluid/structure interactions be well understood. Moreover, underground flows, in particular in sewers, can accelerate and amplify the flow. To take them into account, the model and the numerical resolution should be able to treat the transition between free surface and underground flows.
Tsunamis are another hydrological disaster largely studied. Even if the propagation of the wave is globally well described by the shallow water model in oceans, it is no longer the case close to the epicenter and in the coastal zone where the bathymetry leads to vertical accretions and produces substantial dispersive effects. The non-hydrostatic terms have to be considered and an efficient numerical resolution should be induced.
While viscous effects can often be neglected in water flows, they have to be taken into account in situations such as avalanches, debris flows, pyroclastic flows, erosion processes, ...i.e. when the fluid rheology becomes more complex. Gravity driven granular flows consist of solid particles commonly mixed with an interstitial lighter fluid (liquid or gas) that may interact with the grains and decrease the intensity of their contacts, thus reducing energy dissipation and favoring propagation. Examples include subaerial or subaqueous rock avalanches (e.g. landslides).
Nowadays, simulations of the hydrodynamic regime of a river, a lake or an estuary, are not restricted to the determination of the water depth and the fluid velocity. They have to predict the distribution and evolution of external quantities such as pollutants, biological species or sediment concentration.
The potential of micro-algae as a source of biofuel and as a technological solution for CO2 fixation is the subject of intense academic and industrial research. Large-scale production of micro-algae has potential for biofuel applications owing to the high productivity that can be attained in high-rate raceway ponds. One of the key challenges in the production of micro-algae is to maximize algae growth with respect to the exogenous energy that must be used (paddlewheel, pumps, ...). There is a large number of parameters that need to be optimized (characteristics of the biological species, raceway shape, stirring provided by the paddlewheel). Consequently our strategy is to develop efficient models and numerical tools to reproduce the flow induced by the paddlewheel and the evolution of the biological species within this flow. Here, mathematical models can greatly help us reduce experimental costs. Owing to the high heterogeneity of raceways due to gradients of temperature, light intensity and nutrient availability through water height, we cannot use depth-averaged models. We adopt instead more accurate multilayer models that have recently been proposed. However, it is clear that many complex physical phenomena have to be added to our model, such as the effect of sunlight on water temperature and density, evaporation and external forcing.
Many problems previously mentioned also arise in larger scale systems like lakes. Hydrodynamics of lakes is mainly governed by geophysical forcing terms: wind, temperature variations, ...
One of the booming lines of business is the field of renewable and decarbonated energies. In particular in the marine realm, several processes have been proposed in order to produce electricity thanks to the recovering of wave, tidal and current energies. We may mention water-turbines, buoys turning variations of the water height into electricity or turbines motioned by currents. Although these processes produce an amount of energy which is less substantial than in thermal or nuclear power plants, they have smaller dimensions and can be set up more easily.
The fluid energy has kinetic and potential parts. The buoys use the potential energy whereas the water-turbines are activated by currents. To become economically relevant, these systems need to be optimized in order to improve their productivity. While for the construction of a harbour, the goal is to minimize swell, in our framework we intend to maximize the wave energy.
This is a complex and original issue which requires a fine model of energy exchanges and efficient numerical tools. In a second step, the optimisation of parameters that can be changed in real-life, such as bottom bathymetry and buoy shape, must be studied. Eventually, physical experiments will be necessary for the validation.
The urban environment is essentially studied for air and noise pollutions. Air pollution levels and noise pollution levels vary a lot from one street to next. The simulations are therefore carried out at street resolution and take into account the city geometry. The associated numerical models are subject to large uncertainties. Their input parameters, e.g. pollution emissions from road traffic, are also uncertain. Quantifying the simulation uncertainties is challenging because of the high computational costs of the numerical models. An appealing approach in this context is the use of metamodels, from which ensembles of simulations can be generated for uncertainty quantification.
The simulation uncertainties can be reduced by the assimilation of fixed and mobile sensors. High-quality fixed monitoring sensors are deployed in cities, and an increasing number of mobile sensors are added to the observational networks. Even smartphones can be used as noise sensors and dramatically increase the spatial coverage of the observations. The processing and assimilation of the observations raises many questions regarding the quality of the measurements and the design of the network of sensors.
There is a growing interest for environmental problems at city scale, where a large part of the population is concentrated and where major pollutions can occur. Numerical simulation is well established to study the urban environment, e.g. for road traffic modelling. As part of the smartcity movement, an increasing number of sensors collect measurements, at traditional fixed observation stations, but also on mobile devices, like smartphones. They must properly be taken into account given their number but also their potential low quality.
Pratical applications include air pollution and noise pollution. These directly relate to road traffic. Data assimilation and uncertainty propagation are key topics in these applications.
Human resources
A major event in the year was new positions of J. Sainte-Marie (Détachement at Inria, 2 years position) and of Y. Penel (Advanced Research Position, 3 years position). Two new students have started a PhD (Liudi Lu and Nelly Boulos Al Makary).
Evaluation of the team
This year, the team went through the first evaluation since its creation. The report was very positive, as this excerpt shows:
The activity of the team in modeling and mathematical and numerical analysis has lead to significant contributions in various areas. In particular, we mention the study of models that can reproduce specific ‘dispersive effects,’ observed in nature, or the review of several multi-physics models that incorporate the coupling of heterogeneous systems. The theoretical analysis of the models has often led to the proposal of new algorithmic developments and new numerical techniques and, in general, it has resulted in a significant advancement of scientific knowledge.
Scientific activities There has been major achievements within the team in the framework of dispersive models.
Léa Boittin received the award of the best presentation at GDR-EGRIN summer school in June,
Léa Boittin was rewarded by Best Phd Student Poster Award, at CMWR XXII, Saint-Malo,
Janelle Hammond received a post-doctoral grant from DIM Math Innov 2018.
FREe Surface Hydrodynamics using KInetic SchemeS
Keywords: Finite volume methods - Hydrostatic Navier-Stokes equations - Free surface flows
Functional Description: Freshkiss3D is a numerical code solving the 3D hydrostatic and incompressible Navier-Stokes equations with variable density.
Participants: Fabien Souille, Emmanuel Audusse, Jacques Sainte Marie and Marie-Odile Bristeau
Partners: UPMC - CEREMA
Contact: Jacques Sainte Marie
Keywords: Modeling - Tsunamis
Functional Description: Tsunamaths is an educational platform aiming at simulating historical tsunamis. Real data and mathematical explanations are provided to enable people to better understand the overall process of tsunamis.
Participants: Emmanuel Audusse, Jacques Sainte Marie and Raouf Hamouda
Contact: Jacques Sainte Marie
Keywords: HPC - Model - Software Components - Partial differential equation
Functional Description: Verdandi is a free and open-source (LGPL) library for data assimilation. It includes various such methods for coupling one or several numerical models and observational data. Mainly targeted at large systems arising from the discretization of partial differential equations, the library is devised as generic, which allows for applications in a wide range of problems (biology and medicine, environment, image processing, etc.). Verdandi also includes tools to ease the application of data assimilation, in particular in the management of observations or for a priori uncertainty quantification. Implemented in C++, the library may be used with models implemented in Fortran, C, C++ or Python.
Participants: Dominique Chapelle, Gautier Bureau, Nicolas Claude, Philippe Moireau and Vivien Mallet
Contact: Vivien Mallet
Keyword: Simulation
Functional Description: Polyphemus is a modeling system for air quality. As such, it is designed to yield up-to-date simulations in a reliable framework: data assimilation, ensemble forecast and daily forecasts. Its completeness makes it suitable for use in many applications: photochemistry, aerosols, radionuclides, etc. It is able to handle simulations from local to continental scales, with several physical models. It is divided into three main parts:
libraries that gather data processing tools (SeldonData), physical parameterizations (AtmoData) and post-processing abilities (AtmoPy),
programs for physical pre-processing and chemistry-transport models (Polair3D, Castor, two Gaussian models, a Lagrangian model),
model drivers and observation modules for model coupling, ensemble forecasting and data assimilation.
Participants: Sylvain Doré and Vivien Mallet
Contact: Vivien Mallet
Keyword: Environment perception
Functional Description: This software processes mobile observations collected by the application Ambiciti (previously known as SoundCity). It can merge simulated noise maps with the mobile observations.
Authors: Raphaël Ventura, Vivien Mallet and Guillaume Cherel
Contact: Vivien Mallet
Authors: Jacques Sainte Marie, Marie-Odile Bristeau, Anne-Céline Boulanger, Raouf Hamouda, Emmanuel Audusse, Alain Dervieux, Bijan Mohammadi and David Froger
Partner: UPMC
Contact: Jacques Sainte Marie
Oceanic numerical models are used to understand and predict a wide range of processes from global paleoclimate scales to short-term prediction in estuaries and shallow coastal areas. One of the overarching challenges, and the main topic of the COMMODORE workshop, is the appropriate design of the dynamical cores given the wide variety of scales of interest and their interactions with atmosphere, sea-ice, biogeochemistry, and even societal processes. The construction of a dynamical core is a very long effort which takes years and decades of research and development and which requires a collaborative mixture of scientific disciplines. In , we present a significant number of fundamental choices, such as which equations to solve, which horizontal and vertical grid arrangement is adequate, which discrete algorithms allows jointly computational efficiency and sufficient accuracy, etc.
The basic idea of the method of reflections appeared almost two hundred years ago; it is a method of successive approximations for the interaction of particles within a fluid, and it seems intuitively related to the Schwarz domain decomposition methods, the subdomains being the complements of the particle domains. We show in that indeed there is a direct correspondence between the methods of reflections and Schwarz methods in the two particle/subdomain case. This allows us to give a new convergence analysis based on maximum principle techniques with precise convergence estimates that one could not obtain otherwise. We then show however also that in the case of more than two particles/subdomains, the methods of reflections and the Schwarz methods are really different methods, with different convergence properties. We finally also introduce for the first time coarse corrections for the methods of reflections to make them scalable in the case when the number of particles becomes large.
A previous derivation of the sediment layer model has then been extended. Depending on the scaling chosen for the physical parameters, different models are obtained. The model we are interested in is the non-local model (with a viscosity term). Several numerical schemes are implemented and studied to simulate this model. Only one of these schemes is satisfactory. Simulations of the coupled water-sediment systems are made. The influence of the viscosity is emphasized. Turning on the non-local term allows to simulate dune growth and propagation.
Following the previous work, a numerical scheme for the sediment layer is proposed. The numerical scheme is tested. The influence of the viscosity on the behaviour of the sediment layer is studied. A numerical strategy for the resolution of the coupled model (water layer and sediment layer) is implemented. The behaviour of the coupled system is numerically assessed. Academic test cases are performed.
We model free surface flows where density variations coming e.g. from temperature or salinity differences play a significant role. Starting from the compressible Navier-Stokes system, a model is derived by performing the incompressible limit (the dependence of the density on the pressure is removed). A layer-averaged formulation of the model is proposed. The layer-averaged model satisfies a dissipative energy balance. A numerical scheme is proposed. It verifies several stability properties (positivity, well-balancing, maximum principle on the density). Numerical simulations are performed. The differences with models relying on the classical Boussinesq approximation are shown.
We consider Navier-Stokes equations for compressible viscous fluids in the one-dimensional case with general viscosity coefficients. We prove the existence of global weak solution when the initial momentum
In this paper we investigate the question of the local existence of strong solution for the Korteweg system in critical spaces when
Road traffic emissions of air pollutants depend on both traffic flow and vehicle emission factors. At metropolitan scale, traffic flow can be obtained by traffic assignment models, and emission factors can be computed from the traffic flow using COPERT IV formulas. Global sensitivity analyses, especially the computation of Sobol' indices, was carried out for the traffic model and the air pollutant emissions. In the process, the traffic model was replaced by a metamodel, or surrogate model, in order to reduce the high computational burden. The results identified the most important input parameters, e.g., the demand associated with small travel distances (for the traffic flow) or the gasoline car share (for the air pollutant emissions). Furthermore, the uncertainties in traffic flow and pollutant emissions was quantified by propagating into the model the uncertainties in the input parameters. Large ensembles of traffic flows were generated and evaluated with traffic flow measurements.
In collaboration with IRSN (Institute of Radiation Protection and Nuclear Safety), we investigated the uncertainties of the atmospheric-dispersion forecasts that are used during an accidental release of radionuclides such as the Fukushima disaster. These forecasts are subject to considerable uncertainties which originate from inaccurate weather forecasts, poorly known source term and modeling shortcomings. In order to quantify the uncertainties, we designed a metamodel and investigated the calibration of the probability distribution of the input variables like the source term or the meteorological variables.
An air quality model at urban scale computes the air pollutant concentrations at street resolution based on various emissions, meteorology, imported pollution and city geometry. Because of the computational cost of such model, we previously designed a metamodel using dimension reduction and statistical emulation. Novel work was dedicated to the correction of this metamodel using observational data. The proposed approach builds a corrected metamodel that is still much faster than the original model, but also performs better when compared to new observations.
Urban noise mapping models simulate the propagation of noise, originating from emission sources (e.g., road traffic), in all street of a city, based on its geometry. They are subject to uncertainties due to incomplete and erroneous data. We carried out screening studies in order to evaluate the sensitivity of the computed noise to the uncertain data. Further work dealt with the development of a metamodel, which will open the way to uncertainty quantification. The work was carried out with the model NoiseModelling and applied to the noise mapping of Lorient (France).
We worked on Monte Carlo simulations of wildland fires. The objective was to evaluate how the uncertainties lying in all the inputs of a fire propagation model can be propagated through the model. A careful review of the literature allowed us to define varying intervals for all the uncertain inputs. The Monte Carlo simulations were then evaluated with ensemble scores, using the observations of the final contours for a number of real cases. The ensemble scores were inspired by classical scores used in meteorology, but were adapted to the nature of the fire observations.
With the objective of uncertainty quantification, we worked in on the generation of a metamodel for the simulation of urban air quality, using a complete simulation chain including dynamic traffic assignment, the computation of air pollutant emissions and the dispersion of the pollutant in a city. The traffic model and the dispersion model are computationally costly and operate in high dimension. We employed dimension reduction, and coupled it with Kriging in order to build a metamodel for the complete simulation chain.
Improvements in the FRESHKISS3D code Several improvements have been achieved in FreshKiss3D :
installation step is simpler due to the usage of a YAML file listing third-party libraries;
Mac OS is now supported;
continuous integration is performed on Ubuntu 16 and OSX with different compilers (GCC, Clang) and different builds (debug, release);
a major bug in the computation of fluxes has been fixed;
the number of third-party libraries has been minimized (geomalgo, metis4py);
build automation is now based on CMake (instead of Waf);
documentation has been updated and it is now published during the continuous integration process by means of Gitlab pages;
continuous integration has been optimized (better slaves, parallelization)
A contract (2016-2018) has been made (
A part of the ANR project Hyflo-Eflu relies on a collaboration with the company “HydroTube Energie”. It comprises the recruitment of a young engineer (J. Ledoux) and regular meetings with industrial (Bordeaux) and academic partners (Nantes). See below for more details about the scientific content of this project.
A part of the ANR project ESTIMAIR includes the SME NUMTECH for a commercial deployment of the project results. (Bordeaux) and academic partners (Nantes). See below for more details about the scientific content of this project.
J. Sainte-Marie, C. Guichard, Y. Penel, J. Salomon are part of an agreement between Institut Carnot SMILES (Sorbonne Univ., Thomas Boiveau) and the corporation GTT about the improvement of a modeling tool for gas flows in the isolation spaces of LNG tanks
P. Quémar's PhD thesis is funded by EDF (CIFRE). His PhD is entitled “3D numerical simulations of environmental hydrolics: application to Telemac”.
Project acronym: MFG
Project title: Mean Field Games
Coordinator: Sébastien Boyaval (LHSV/ENPC)
Funding: 299 160 euros.
CMean field game theory (MFG) is a new and active field of mathematics, which analyses the dynamics of a very large number of agents. Introduced about ten years ago, MFG models have been used in different fields: economics, finance, social sciences, engineering,... MFG theory is at the intersection of mean field theory, mathematical game theory, optimal control, stochastic analysis, variation calculation, partial differential equations and scientific calculation. Drawing on an internationally recognized French team on the subject, the project seeks to obtain major contributions in 4 main directions: the "medium field" aspect (i.e., how to obtain macroscopic models from microscopic models); the analysis of new MFG systems; their numerical analysis; the development of new applications. In this period of rapid expansion of MFG models, the project seeks to foster French leadership in the field and attract new researchers from related fields.
Program: ANR Défi de tous les savoirs (DS10) 2015
Project acronym: INFAMIE
Project title: INhomogeneous Flows : Asymptotic Models and Interfaces Evolution
Coordinator: Raphaël Danchin (Univ. Paris-Est)
Funding: 232 960 euros.
Our project aims at a better mathematical understanding of several models for the evolution of inhomogeneous flows. Through three main lines of research (see below), we will pursue a twofold final objective. First, we want to develop the current theory of regular solutions for several equations for the evolution of fluids, proposing a new approach and developing tools that are likely to be efficient in various areas of PDEs. Second, for a few selected concrete systems that describe flows in the earth environment or in astrophysics, we wish to use this general approach to extract as much information as possible concerning the qualitative behavior of the solutions.
Program: ANR Défi 1 “Gestion sobre des ressources et adaptation au changement climatique” (JCJC)
Project acronym: SEDIFLO
Project title: Modelling and simulation of solid transport in rivers
Coordinator: Sébastien Boyaval (LHSV/ENPC)
Based on recent theoretical and experimental results, this project is aimed at modelling transport of sediments within rivers. It will rely on innovations from the point of view of rheology as well as advanced mathematical tools (asymptotic model reduction, PDE discretisation).
ANR project call: Energies marines renouvelables
Project acronym: Hyflo-Eflu
Project title: Hydroliennes flottantes et énergie fluviale
Coordinator: Julien Salomon
The project is a collaboration between the Inria-team ANGE, specialist of free surface flow and optimisation, and the industrial developers of the turbine, HYDROTUBE ENERGIE. The objective of the project HyFlo-EFlu is to deliver a numerical software able to simulate the dynamic of a floating water turbine in real context. For the academic partner, the main challenge is in the simulation of the floating structure at the scale of the river, and the modelling of the vertical and horisontal axis turbine. For the industrial partner, the objective is the validation of the stability of the structure and the performance in term of energy production.
ANR project call: Transformations et inter-conversions énergétiques
Project acronym: CHARMS
Project title: Modèles de réservoirs quantitatifs pour les systèmes hydrothermaux complexes
Coordinator: Simon Lopez (BRGM)
Funding: 73k euros for LJLL (in 767k euros for the whole project)
CHARMS ANR project is focused on the mathematical methods and software tools dedicated to the simulation of the physical models issued from geothermal engineering. The final objective is the achievement of a highly parallel code, validated on realistic cases.
CNRS project call: LEFE
Project acronym: MOCHA
Project title: Multi-dimensiOnal Coupling in Hydraulics and data Assimilation
Coordinator: Martin Parisot
Funding: 14k euros
In collaboration with S. Barthélémy, N. Goutal, S. Ricci, M. Hoang Le.
Multi-dimensionnal coupling in river hydrodynamics offers a conveninent solution to properly model complex flow while limiting the computational cost and making the most of pre-exsiting models. The project aims to adapt the lateral interface coupling proposed in to the implicit version and test it on real data for the Garonne River.
In the aftermath of the ADT In@lgae (2013–2015), we developed a simulation tool for microalgae culture. An Inria Project Lab “Algae in Silico” has started in collaboration with Inria teams BIOCORE and DYLISS. It concerns microalgae culture for biofuel production and the aim is to provide an integrated platform for numerical simulation “from genes to industrial processes”.
CityLab@Inria studies ICT solutions toward smart cities that promote both social and environmental sustainability.
EGRIN stands for Gravity-driven flows and natural hazards. J. Sainte-Marie is the head of the scientific committee of this CNRS research group and A. Mangeney is a member of the committee. Other members of the team involved in the project are local correspondents. The scientific goals of this project are the modelling, analysis and simulation of complex fluids by means of reduced-complexity models in the framework of geophysical flows.
ANR project call: DS0104
Project acronym: FireCaster
Project title: Plateforme de prévision incendie et de réponse d'urgence
Coordinator: Jean-Baptiste Filippi (Univ. Corse)
Funding: 442k euros
The goal of the FireCaster project is to prototype a fire decision support system at the national scale to estimate upcoming fire risk (H+24 to H+48) and in case of crisis, to predict fire front position and local pollution (H+1 to H+12).
ANR project call: DS0601
Project acronym: CENSE
Project title: Caractérisation des environnements sonores urbains : vers une approche globale associant données libres, mesures et modélisations
Coordinator: Judicaël Picaut (IFSTTAR)
Funding: 856k euros
The CENSE project aims at proposing a new methodology for the production of more realistic noise maps, based on an assimilation of simulated and measured data through a dense network of low-cost sensors.
ANR project call: DS0106
Project acronym: RAVEX
Project title: Développement d'une approche intégrée pour la réduction des Risques Associés au Volcanisme EXplosif, de la recherche sur l'aléa aux outils de gestion de crise : le cas de la Martinique
Coordinator: Olivier Roche (IRD)
Funding: 619k euros
ANR project call: DS0708
Project acronym: CINE-PARA
Project title: Méthodes de parallélisation pour cinétiques complexes
Coordinator: Yvon Maday (LJLL)
The project SLIDEQUAKES is about detection and understanding of landslides by observing and modelling gravitational flows and generated earthquakes and is funded by the European Research Council (2 million euros). More precisely, it deals with the mathematical, numerical and experimental modelling of gravitational flows and generated seismic waves coupled with field measurements to better understand and predict these natural hazards and their link with volcanic, seismic and climatic activities.
Title: Energy oriented Centre of Excellence for computer applications
Program: H2020
Duration: October 2015 - October 2018
Coordinator: Édouard Audit (CEA)
Partners: CEA (Commissariat à l'Énergie Atomique et aux Énergies Alternatives, France), Forschungszentrum Julich (Germany), Max Planck Gesellschaft (Germany), ENEA (Agenzia Nazionale Per le Nuove Tecnologie, l'energia E Lo Sviluppo Economico Sostenibile, Italy), CERFACS (European Centre for Research and Advanced Training in Scientific Computing, France), Instytut Chemii Bioorganicznej Polskiej Akademii Nauk (Poland), Universita Degli Studi di Trento (Italy), Fraunhofer Gesellschaft (Germany), University of Bath (United Kingdom), CYL (The Cyprus Institute, Cyprus), CNR (National Research Council of Italy), Université Libre de Bruxelles (Belgium), BSC (Centro Nacional de Supercomputacion, Spain)
Inria contact: Michel Kern (Serena team)
Abstract: The aim of the projevt is to establish an Energy Oriented Centre of Excellence for computing applications (EoCoE). EoCoE (pronounce “Echo”) will use the prodigious potential offered by the ever-growing computing infrastructure to foster and accelerate the European transition to a reliable and low carbon energy supply. To achieve this goal, we believe that the present revolution in hardware technology calls for a similar paradigm change in the way application codes are designed. EoCoE will assist the energy transition via targeted support to four renewable energy pillars: Meteo, Materials, Water and Fusion, each with a heavy reliance on numerical modelling. These four pillars will be anchored within a strong transversal multidisciplinary basis providing high-end expertise in applied mathematics and HPC. EoCoE is structured around a central Franco- German hub coordinating a pan-European network, gathering a total of 8 countries and 23 teams. Its partners are strongly engaged in both the HPC and energy fields; a prerequisite for the long-term sustainability of EoCoE and also ensuring that it is deeply integrated in the overall European strategy for HPC. The primary goal of EoCoE is to create a new, long lasting and sustainable community around computational energy science. At the same time, EoCoE is committed to deliver high- impact results within the first three years. It will resolve current bottlenecks in application codes, leading to new modelling capabilities and scientific advances among the four user communities; it will develop cutting-edge mathematical and numerical methods, and tools to foster the usage of Exascale computing. Dedicated services for laboratories and industries will be established to leverage this expertise and to foster an ecosystem around HPC for energy. EoCoE will give birth to new collaborations and working methods and will encourage widely spread best practices.
Program: CNRS PICS (projet international de collaboration scientifique)
Project acronym: NHML
Project title: non-hydrostatic multilayer models
Duration: 01/17-12/19
Coordinator: Yohan Penel (Inria)
Other partners: IMUS (Sevilla, Spain)
Other Participants: Enrique Fernández-Nieto (Sevilla), Tomas Morales de Luna (Cordoba)
Funding: 12k euros
Abstract: This collaboration aims at designing a hierarchy of multilayer models with a non-hydrostatic pressure as a discretisation along the vertical axis of the Euler equations. The hierarchy relies on the degree of approximation of the variables discretised with a Discontinuous Galerkin method for the vertical direction. These innovative models will imply a theoretical study and the development of numerical tools in dimensions 1 and 2 before the modelling of other physical phenomena (viscosity effects, ...).
Four collaborations with foreign colleagues are to be mentioned:
Spain - A collaboration with Spanish researchers has been initiated in 2016 to derive accurate models and effecient algorithms for free surface flows including non-hydrostatic effects. ANGE applied in 2018 to the Inria Associate Team programme in order to strenghten the collaboration.
USA A joint work with R. LeVeque (Univ. Seattle) and M. Berger (New York Univ.) consists in modelling the impact of asteroids on the generation of tsunamis.
Germany A collaboration with researchers from the University of Constance has been initiated in 2018 about domain decomposition and identifaction algorithms (G. Ciaramella, S. Volkwein).
Hong-Kong A collaboration with F. Kwok on time parallelization for assimilation algorithm has been initiated in 2018.
Y. Penel spent twice two weeks (May, October)at the university of Sevilla (Spain) to collaborate with E. Fernández-Nieto.
G. Ciaramella visited J. Salomon (28.05-01.06) to work on a reduction method for identification problem.
Y. Penel and J. Sainte-Marie organised (with E. Fernández-Nieto) the workshop
“non-hydrostatic effects in oceanography ” that took place
at Sevilla univ. on 15-16th October and that gathered 35 international researchers
J. Sainte-Marie took part of the organization of the 6th EGRIN summer school that took place at Le Lioran from 18th to 21st of June
and that gathered 40 researchers
J. Sainte-Marie took part of the organization of the Workshop COMMODORE "Community for the numerical modeling of the global, regional and coastal ocean"
B. Haspot and Y. Penel organise the monthly ANGE seminar
J. Salomon co-organises the LJLL-Inria meetings
J. Salomon co-organised the minisymposium "Domain-decomposition methods for integral equation problems " at the 25th International Domain Decomposition Conference, DD XXV, in St. John's, Newfoundland, Canada, July 23-27, 2018.
L. Boittin co-organises the Junior Seminar at Inria–Paris.
M. Parisot and J. Salomon organise a workshop entitled “Scientific computing and optimisation processes for renewable energies”
at Inria
The summary of the reviewing activities of the team is given in the next table.
Member | Journal |
Julien Salomon | CRAS, SIAM SISC |
Cindy Guichard | J. Comp. Phys., J. Sci. Comp., CRAS, |
J. Comp. Math., Num. Math. | |
Jacques Sainte-Marie | M2AN, Computer and Fluids, Ocean Modelling, J. Comp. Phys., |
J. Sci. Comp. Adances in Comp. Math. | |
Martin Parisot | J. Hydraulic Research, Computers and Fluids, |
J. Comp. Phys., J. de Math. Pures et Appliquées | |
Vivien Mallet | ANR, Journal of Machine Learning Research |
Edwige Godlewski | Sinum |
Conference | Location | Month | Members involved |
Julien Salomon | 7-th Parallel-in-time Integration Workshop (PinT 2018). | Roscoff, France | 02-05/05/2018 |
Julien Salomon | 25-th International Conference on Domain Decomposition Methods (DD25). | St-Johns, Canada | 23-27/07/18 |
Julien Salomon | Séminaire du laboratoire de mathématiques Blaise Pascal. | Clermont-Ferrand, France | 01/02/18 |
Julien Salomon | Séminaire du CMAP. | Palaiseau, France | 15/5/18 |
Julien Salomon | Séminaire du Laboratoire J.-L. Lions | Paris, France | 30/03/18 |
Julien Salomon | Séminaire du groupe d'analyse | Universität Konstanz | 14/11/18 |
Fabien Wahl | Simulation et Optimisation pour les Energies Marines Renouvelables | Inria Paris | 11/01/18 |
Fabien Wahl | GdT ANGE | Inria Paris | 10/10/18 |
Fabien Wahl | EGRIN | Le Grand Lioran | 18/06/18 |
Bilal Al Taki | Journée interne du LJLL | Paris diderot (P7) | 05/04/18 |
Bilal Al Taki | Séminaire du laboratoire | Marseille | 20/11/18 |
Frédéric Allaire | 8th International Conference on Forest Fire Research (ICFFR) | Coimbra, Portugal | 12-16/11/18 |
Virgile Dubos, Martin Parisot | Non-hydrostatic effects in oceanography | Séville, Espagne | 15-16/10/18 |
Virgile Dubos | 18th Spanish-French Sch. J-L. Lions, Num. Sim. in Phy. and Eng. | Las Palmas, Espagne | 25-29/06/18 |
Cindy Guichard | rencontres Inria-LJLL en calcul scientifique | Paris | 05/11 |
Cindy Guichard | Mini-symposium, CANUM | Cap d’Agde | 29/05 |
Cindy Guichard | séminaire d’analyse numérique, CEA/DIF | Bruyères-le-Châtel | 03/05/18 |
Cindy Guichard | journée interne du LJLL | Paris | 05/04/18 |
Cindy Guichard | séminaire d’analyse numérique des EDP | univ. Orsay | 22/03/18 |
Yohan Penel | Mini-symposium, CANUM | Cap d’Agde | 29/05/18 |
Yohan Penel | GDR Manu (poster) | Roscoff, France | 02/07/18 |
Yohan Penel | Workshop "non-hydrostatic effects in oceanography" | Séville, Espagne | 16/10/18 |
Jacques Sainte-Marie | Plenary in " Free Surface Flows: from Hydrostatic to Non-Hydrostatic Models" | Saint-Malo | 6/6/18 |
Jacques Sainte-Marie | Séminaire du laboratoire N. Oresme - université de Caen | Caen | 12/02/18 |
Léa Boittin | GdT ANGE | Inria Paris | 21/02/18 |
Léa Boittin | GTT LJLL | LJLL, Paris | 30/1 |
Léa Boittin | CMWR XXII (poster) | Saint-Malo | 04/06/18 |
Léa Boittin | EGRIN | Le Grand Lioran | 18/6/18 |
Martin Parisot | Seminaire d'équipe LEMON | Montpellier | 6/2/18 |
Martin Parisot | SIMAI-UMI Congres | Wroclaw, Poland | 16-20/09/18 |
Martin Parisot | Séminaire du Laboratoire Jean Leray | Nantes | 11/10/18 |
Martin Parisot | Conference Balance laws in fluid mechanics, geophysics, biology | Orléans | 19-22/10/18 |
Martin Parisot | Séminaire "Math et Eau" | Montpellier | 25/10/18 |
Martin Parisot | Colloque LEFE | Clermont-Ferrand | 28-30/03/18 |
Martin Parisot | Workshop Non Hydro, Séville | Séville | 10/18 |
Jacques Sainte-Marie | Séminaire du laboratoire de mathématiques | Beyrouth université | 19/12/2018 |
Vivien Mallet | Semaine "data science", ENPC | Marne-la-Vallée | 02/02/18 |
Vivien Mallet | Journées scientifiques Inria | Bordeaux | 28/06/18 |
Vivien Mallet | Observations, AI and Sustainable Development | Paris | 24/09/18 |
Vivien Mallet | Séminaire au laboratoire d'aérologie | Toulouse | 03/07/18 |
Boris Haspot | Séminaire Evry | Evry | 01/18 |
Boris Haspot | Séminaire LJLL | Paris | 11/18 |
Boris Haspot | Hyp 2018 Penn State | Penn State | 06/18 |
Boris Haspot | Workshop Non Hydro, Séville | Séville | 10/18 |
Janelle Hammond | CANUM | Cap d’Agde | 29/05 |
Yohan Penel is a member of the Council Administration of SMAI (2015-2018).
Yohan Penel was rewiewer for the grant CNRS INSU LEFE
Vivien Mallet was reviewer for ANR
Member | Level | Institution | Duration | Type | Topic |
J. Salomon | M2 | Univ. Paris-Dauphine | 15 | CM | Cours de rentrée : méthodes numériques pour les EDP |
J. Salomon | M2 | Univ. Paris-Dauphine | 30 | CM | Méthodes numériques pour des modèles incluants des EDP |
L. Lu | L1 | SU | 27.4 | TD | Analyse et algèbre pour les sciences |
B. Al Taki | L1 | SU | 36 | TD | Analyse et algèbre pour les sciences |
F. Allaire | L1 | SU | 38.5 | TD | Calculus |
V. Dubos | L3 | Polytech Sorbonne | 32 | TP | Mathématiques appliquées |
V. Dubos | M1 | Polytech Sorbonne | 14+22 | CM+TP | Traitement numérique |
V. Dubos | L3 | Polytech Sorbonne | 10 | TP | Projet d'initiation |
C. Guichard | M2 | SU | 22 | CM+TD | Méthodes numériques |
C. Guichard | M1 | SU | 58 | TP | Fondements des méthodes numériques |
C. Guichard | L3 | SU | 21 | TP | Python |
C. Guichard | M1 | SU | 18 | CM | Mise en oeuvre de la méthode des éléments finis |
B. Di Martino | L1 | Univ. Corse | 18 | CM+TD | Techniques mathématiques |
et physiques pour les sciences de la vie | |||||
B. Di Martino | L2 | Univ. Corse | 72 | CM+TD+TP | Analyse et TP Python Sage algèbre et analyse |
B. Di Martino | L3 | Univ. Corse | 54 | CM+TD+TP | Analyse numérique matricielle |
B. Di Martino | M2 | Univ. Corse | 24 | CM+TD+TP | Modélisation master |
Gestion Intégrée du Littoral et Valorisation Halieutique | |||||
Y. Penel | L2 | SU | 12 | CM | Analyse vectorielle et intégrales multiples |
Y. Penel | M1 | Univ. Paris Descartes | 37.5 | CM+TD+TP | Modélisation déterministe en sciences du vivant |
J. Sainte-Marie | M1 | IPGP | 40 | CM | Modélisation des écoulements gravitaires |
J. Sainte-Marie | M2 | IPGP | 30 | CM et TP | Méthodes numériques, appli. géosciences |
J. Sainte-Marie | M2 | SU | 20 | CM | Méthodes numériques pour les systèmes hyperboliques |
Applications aux énergies renouvelables | |||||
N. Boulos | L1 | Paris 13 | 48 | TD | Mathématiques pour le parcours aménagé |
L. Boittin | L3 | SU | 24,5 | TD | Méthodes numériques pour les EDO |
M. Parisot | L3 | Polytech Sorbonne | 46 | CM+TP | Méthodes numériques pour l'ingénieur |
J. Sainte-Marie | M2 | Université de Beyrouth | 15 | CM | Modélisation et méthodes numériques en géosciences |
V. Mallet | M2 | ENPC | 4.5 | CM | Modélisation de la qualité de l'air |
V. Mallet | M2 | ENPC | 3 | TP | Simulation de la dispersion atmosphérique |
V. Mallet | M2 | ENPC | 7 | TP | Assimilation de données pour la géophysique |
E. Godlewski | M1 | SU | 30 | CM | Bases des méthodes numériques |
E. Godlewski | M2 | SU | 18 | TD | analyse numérique pour les EDP |
E. Godlewski | L1 | SU | 12 | CM | Calcul Matriciel |
E. Godlewski | L2 | SU | 22 | TD | OIP : orientation et insertion |
professionnelle en mathématiques | |||||
E. Godlewski | M1 | SU | 20 | TD | direction d'études en M1 |
E. Godlewski | M2 | SU | 10 | CM | Modèles hyperboliques d'écoulements |
complexes dans le domaine de l'énergie | |||||
J. Hammind | L3 | SU | 25 | TP | Approximation numérique des EDO |
Supervisor ANGE | Type | Name | Institution | Time | Title |
JS | PhD | Sebastian Reyes-Riffo | Paris-Dauphine | 2016-2019 | Méthodes numériques pour les énergies marines renouvelables |
JS, VM | PhD | Antoine Lesieur | Inria | 2017-2020 | Estimation d’état et modélisation inverse appliquées à la pollution |
sonore en milieu urbain | |||||
JS | PhD | Nadia Jbili | Paris-Dauphine | 2016-2019 | Contrôle optimal pour la résonance magnétique nucléaire |
JS, JSM | PhD | Liudi Lu | Inria | 2018-2021 | Approches Lagrangiennes pour la modélisation et l’optimisation |
du couplage hydrodynamique-photosynthèse | |||||
JSM, VM | PhD | Frédéric Allaire | Inria | 2017-2020 | Quantification du risque incendie par méta-modélisation |
de la propagation de feux de forêt | |||||
YP, CG, JSM | PhD | Virgile Dubos | SU | 2017-2020 | Numerical methods for the elliptic/parabolic parts of non-hydrostatic |
fluid models | |||||
BDM, BH | Post Doc | Bilal AL Taki | Inria | 09/17-12/18 | Understanding and modeling the rheology of complex surface flow |
NA, EA, MP | stage M2 | Nelly BOULOS | Inria | 04-08/2018 | Analyse et simulation de modèles d'écoulement à surface libre intégrés |
selon la verticale | |||||
EA, MP, JSM, MOB | PhD | Léa Boittin | Paris 6 | 2015-2019 | Modelling, analysis and efficient numerical resolution |
for erosion processes, | |||||
MP, NA, EA, MP | PhD | Nelly BOULOS | Paris 13 | 2018-2021 | Modélisation et simulation numérique de la dynamique d'un acquifère |
érodable | |||||
VM | PhD | Ngoc Bao Tran Le | Inria | 2016-2019 | Uncertainty quantification based on model reduction for |
atmospheric dispersion | |||||
VM | Post Doc | Janelle Hammond | Inria | 2017-2019 | Uncertainty quantification, metamodeling and data assimilation applied |
to urban air quality | |||||
EA, MP,JSM | PhD | Léa Boittin | inria | 2016-2019 | Modelling, analysis and efficient numerical resolution for erosion processes |
CG, EG, | PhD | Fabien Wahl | SU | 2015-2018 | Modelling and analysis of interactions between free surface flows |
and floating structures | |||||
MP ,JSM | |||||
JS, JSM | Stage M2 | Liudi Lu | Inria | 04-08/2018 | Approches Lagrangiennes pour la réduction de modèle |
JS | Stage M2 | Quentin Petit | Uni. Paris-Dauphine | 05-07/2018 | An Approximation for a First Order Mean Field Game Problem |
by a Discrete MeanField Game. | |||||
YP | Stage M2 | Davor Kumozec | Novi Sad, Serbia | 03-07/2018 | Numerical method of characteristics: extensions in dimensions 1 and 2 |
YP | Stage M2 | Tanja Dukic | Novi Sad, Serbia | 03-07/2018 | Well-posedness of a 4-equation low Mach number model |
MP | Stage M2 | Noor Ben Jebria | LHSV | 04-08/2018 | Couplage multi-dimensionnel en hydraulique, application sur |
le cas test de la rivière Garonne. | |||||
JS | Stage M1 | Paul Brouté | Inria | 05-07/2018 | Parallélisation en temps pour les systèmes de type Volterra-Lotka |
JS : J. Salomon, VM : Vivien Mallet, JSM : Jacques Sainte-Marie, YP : Yohan Penel, CG : Cindy Guichard, BDM : Bernard Di Martino, BH : Boris Haspot, NA: Nina Aguillon, EA : Emmanuel Audusse, MP : Martin Parisot, EG : Edwige Godlewski
Member | Date | Type (PhD, HdR) | role | Name | Institution | Title |
JS | Novembre | PhD | rapporteur | Quentin Ansel | Univ. Dijon, TUM Munich | Optimal control ofinhomogeneous spin ensembles: |
Applications in NMR and Quantum optics | ||||||
JS | Décembre | PhD | rapporteur | Pierre Terrier | ENPC, Université Paris-Est | Simulations numériques pour la prédiction de l’évolution microstructurale |
d’alliages ferritiques.Une étude de la dynamique d’amas. | ||||||
JS | Décembre | PhD | rapporteur | Amina Benaceur | ENPC, Université Paris-Est | Réduction de modèles en thermique etmécanique non-linéaires |
YP | Septembre | comité de mi-thèse | examinateur | Moustoifa Rafiou | Univ. Toulon | Modélisation et simulation numérique d'un écoulement à faible |
nombre de Mach. Application à un réacteur à eaux pressurisées. | ||||||
JSM | Novembre | PhD | rapporteur | Nicolas Peton | IFPEN et univ. Paris-Saclay | Étude et simulation d'un modèle stratigraphique |
advecto-diffusif non-linéaire avec frontières mobiles | ||||||
JSM | Janvier | PhD | président | Charles Demay | EDF et univ. Savoie Mont-Blanc | Modelling and simulation of transient air-water two-phase flows in hydraulic pipes |
EG | mars | PhD | membre | Alexis Marboeuf | Ecole Polytechnique | Schémas ALE multi-matériaux totalement conservatifs pour l'hudrodynamique |
EG | juillet | PhD | présidente | Camilla Fiorini | UVSQ | Analyse de sensibilité pour systèmes hyperboliques non linéaires |
EG | octobre | PhD | présidente | Julie Llobell | UCA (Nice) | Schémas Volumes Finis à mailles décalées pour la dynamique des gaz |
EG | novembre | PhD | présidente | Nicolas Cagnart | SU | Quelques approches non linéaires en réduction de complexité |
EG | novembre | PhD | rapporteure | David Iampetro | AMU (EDF Saclay) | Contribution à la simulation d'écoulements diphasiques |
compressibles à faible vitesse en présence de sauts de | ||||||
pression par approches homogène et bifluide. | ||||||
VM | Juin | PhD | directeur de thèse | Raphaël Ventura | Inria-Paris | Estimation de la pollution sonore en milieu urbain par |
assimilation d'observations mobiles |
JS : J. Salomon, VM : Vivien Mallet, JSM : Jacques Sainte-Marie, YP : Yohan Penel, EG : Edwige Godlewski
Julien Salomon is a member of the "Comité des usagers de la rue Barrault" in view of the move of Paris Inria Center to Rue Barrault.
Julien Salomon wrote a vulgarization article "Décomposer et itérer pour résoudre un problème " for the CNRS website " Images des mathématiques " (12/2018)
Edwige Godlewski is the president of the "commission française pour l'enseignement des mathématiques" (CFEM)
Jacques Sainte-Marie is a member of the "Groupe de travail : Recherche et développement durable" at the French Ministry of Research.
Julien Salomon took part of the "Salon Culture et Jeux mathématiques" - Stand AMIES (Paris, 24/05/18)
Julien Salomon gave a talk at Waterford Kamhlaba United World College, Mbabane, Eswatini (Swaziland, 5/8/2018).
Julien Salomon took part of "Fête de la science", and gave a talk at école rue st-Isaure, 18ème (Paris,11/10/2018)
Léa Boittin 25/5/18 took part of the "Salon Culture et Jeux mathématiques" - Stand AMIES ( Paris, 25/05/18)
Vivien Mallet gave a talk "Bruit dans la ville", for the association "Versailles environnement initiative" (01/12/18)
Julien Salomon gave talk (3.4.18) at the internal meeting "La demi-heure de science": "Décomposer et itérer pour résoudre un problème complexe, quelques exemples en calcul scientifique".
Anne Mangeney gave talk (4.9.18) at the internal meeting "La demi-heure de science": "Les ondes sismiques : une mine d’informations sur les risques naturels".