Approximation numérique de Systèmes Hyperboliques Non-linéaires Conservatifs ou Non-conservatifs

Les travaux présentés dans ce document s'inscrivent dans le cadre de la simulation numérique d'écoulements compressibles et couplés ou non avec des champs magnétiques. Les difficultés rencontrées proviennent d'une part part de la prise en compte de phénomènes physiques complexes (Magnétohydrodynamique, Equations de Saint-Venant, Euler avec gravité,...) nécessitant des méthodes numériques innovantes et d'autre part du contexte d'utilisation industriel de plus en plus exigeant en terme de précision et robustesse. Pour ces raisons, les outils de simulation numérique doivent être fondées le plus possible sur des techniques numériques basées sur une approche rigoureuse garantissant leur robustesse et leur fiabilité. Le cadre mathématique commun à tous les modèles étudiés ici est celui des systèmes hyperboliques non-linéaires, avec ou sans terme source et éventuellement non-conservatifs. L’objectif de ce travail est donc de présenter un cadre numérique théorique général permettant de traiter cette classe de modèles.Les travaux abordés dans ce document se déclinent en trois parties selon le type de système traité. La première partie concerne la résolution numérique de systèmes hyperboliques homogènes. Une classe de solveurs de Riemann (solveurs simples) est caractérisée dans ce cadre-là et des solveurs entropiques et positifs sont développés pour les cas particuliers de la Dynamique des gaz et de la MHD. La deuxième partie concerne les systèmes hyperboliques non-linéaires avec terme source. On caractérise pour ceux-ci la classe des solveurs simples. Le problème crucial des solutions numériques d'équilibre est abordé aussi. Des solveurs équilibre entropiques sont développés pour la Dynamique des gaz avec gravité ainsi que pour le système de Saint Venant . Enfin, dans la dernière partie on aborde la résolution numérique des systèmes non-conservatifs. On définit pour ceux-ci la classe des solveurs simples et on fournit plusieurs solveurs entropiques pour l'exemple du système de Powell pour la MHD. Dans chacune des trois parties, un premier fil conducteur est suivi, à savoir construire de la façon la plus simple possible un solveur de Riemann. Cette idée donne lieu à la notion de solveur simple. D'autre part, les applications visées sont toutes des applications physiques, au sens où les systèmes hyperboliques associés dérivent tous de la mécanique des fluides et possèdent donc des propriétés structurelles remarquables. En particulier, ces systèmes possèdent à la fois une version dans un système de coordonnées eulériennes et une version dans un système de coordonnées lagrangiennes. Le deuxième fil conducteur est alors la transposition du cadre continu au cadre discret de la dualité entre formulation lagrangienne et formulation eulérienne. En pratique, une correspondance biunivoque entre les solveurs pour la forme eulérienne et les solveurs pour la forme lagrangienne est établie

Numerical simulation of ablation: study of fluid-solid coupling

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Couplage de l'effet Landau avec l'amplification Raman

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SOME ACOUSTIC-TRANSPORT SPLITTING SCHEMES FOR TWO-PHASE COMPRESSIBLE FLOWS

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A second order Cartesian finite volume method for elliptic interface and embedded Dirichlet problems

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The DUNE Far Detector Vertical Drift Technology, Technical Design Report

International audienceDUNE is an international experiment dedicated to addressing some of the questions at the forefront of particle physics and astrophysics, including the mystifying preponderance of matter over antimatter in the early universe. The dual-site experiment will employ an intense neutrino beam focused on a near and a far detector as it aims to determine the neutrino mass hierarchy and to make high-precision measurements of the PMNS matrix parameters, including the CP-violating phase. It will also stand ready to observe supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector implements liquid argon time-projection chamber (LArTPC) technology, and combines the many tens-of-kiloton fiducial mass necessary for rare event searches with the sub-centimeter spatial resolution required to image those events with high precision. The addition of a photon detection system enhances physics capabilities for all DUNE physics drivers and opens prospects for further physics explorations. Given its size, the far detector will be implemented as a set of modules, with LArTPC designs that differ from one another as newer technologies arise. In the vertical drift LArTPC design, a horizontal cathode bisects the detector, creating two stacked drift volumes in which ionization charges drift towards anodes at either the top or bottom. The anodes are composed of perforated PCB layers with conductive strips, enabling reconstruction in 3D. Light-trap-style photon detection modules are placed both on the cryostat's side walls and on the central cathode where they are optically powered. This Technical Design Report describes in detail the technical implementations of each subsystem of this LArTPC that, together with the other far detector modules and the near detector, will enable DUNE to achieve its physics goals

The DUNE Far Detector Vertical Drift Technology, Technical Design Report

International audienceDUNE is an international experiment dedicated to addressing some of the questions at the forefront of particle physics and astrophysics, including the mystifying preponderance of matter over antimatter in the early universe. The dual-site experiment will employ an intense neutrino beam focused on a near and a far detector as it aims to determine the neutrino mass hierarchy and to make high-precision measurements of the PMNS matrix parameters, including the CP-violating phase. It will also stand ready to observe supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector implements liquid argon time-projection chamber (LArTPC) technology, and combines the many tens-of-kiloton fiducial mass necessary for rare event searches with the sub-centimeter spatial resolution required to image those events with high precision. The addition of a photon detection system enhances physics capabilities for all DUNE physics drivers and opens prospects for further physics explorations. Given its size, the far detector will be implemented as a set of modules, with LArTPC designs that differ from one another as newer technologies arise. In the vertical drift LArTPC design, a horizontal cathode bisects the detector, creating two stacked drift volumes in which ionization charges drift towards anodes at either the top or bottom. The anodes are composed of perforated PCB layers with conductive strips, enabling reconstruction in 3D. Light-trap-style photon detection modules are placed both on the cryostat's side walls and on the central cathode where they are optically powered. This Technical Design Report describes in detail the technical implementations of each subsystem of this LArTPC that, together with the other far detector modules and the near detector, will enable DUNE to achieve its physics goals

The DUNE Far Detector Vertical Drift Technology, Technical Design Report

International audienceDUNE is an international experiment dedicated to addressing some of the questions at the forefront of particle physics and astrophysics, including the mystifying preponderance of matter over antimatter in the early universe. The dual-site experiment will employ an intense neutrino beam focused on a near and a far detector as it aims to determine the neutrino mass hierarchy and to make high-precision measurements of the PMNS matrix parameters, including the CP-violating phase. It will also stand ready to observe supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector implements liquid argon time-projection chamber (LArTPC) technology, and combines the many tens-of-kiloton fiducial mass necessary for rare event searches with the sub-centimeter spatial resolution required to image those events with high precision. The addition of a photon detection system enhances physics capabilities for all DUNE physics drivers and opens prospects for further physics explorations. Given its size, the far detector will be implemented as a set of modules, with LArTPC designs that differ from one another as newer technologies arise. In the vertical drift LArTPC design, a horizontal cathode bisects the detector, creating two stacked drift volumes in which ionization charges drift towards anodes at either the top or bottom. The anodes are composed of perforated PCB layers with conductive strips, enabling reconstruction in 3D. Light-trap-style photon detection modules are placed both on the cryostat's side walls and on the central cathode where they are optically powered. This Technical Design Report describes in detail the technical implementations of each subsystem of this LArTPC that, together with the other far detector modules and the near detector, will enable DUNE to achieve its physics goals

The DUNE Far Detector Vertical Drift Technology, Technical Design Report

DUNE is an international experiment dedicated to addressing some of the questions at the forefront of particle physics and astrophysics, including the mystifying preponderance of matter over antimatter in the early universe. The dual-site experiment will employ an intense neutrino beam focused on a near and a far detector as it aims to determine the neutrino mass hierarchy and to make high-precision measurements of the PMNS matrix parameters, including the CP-violating phase. It will also stand ready to observe supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector implements liquid argon time-projection chamber (LArTPC) technology, and combines the many tens-of-kiloton fiducial mass necessary for rare event searches with the sub-centimeter spatial resolution required to image those events with high precision. The addition of a photon detection system enhances physics capabilities for all DUNE physics drivers and opens prospects for further physics explorations. Given its size, the far detector will be implemented as a set of modules, with LArTPC designs that differ from one another as newer technologies arise. In the vertical drift LArTPC design, a horizontal cathode bisects the detector, creating two stacked drift volumes in which ionization charges drift towards anodes at either the top or bottom. The anodes are composed of perforated PCB layers with conductive strips, enabling reconstruction in 3D. Light-trap-style photon detection modules are placed both on the cryostat's side walls and on the central cathode where they are optically powered. This Technical Design Report describes in detail the technical implementations of each subsystem of this LArTPC that, together with the other far detector modules and the near detector, will enable DUNE to achieve its physics goals