Author: Vladimir Duffal
Publisher:
ISBN:
Category :
Languages : fr
Pages : 0
Book Description
Cette thèse est consacrée à la modélisation de la turbulence avec des approches hybrides RANS-LES. Ces approches permettent d'assurer le meilleur compromis entre, d'une part, la capacité de la LES à capturer les structures instationnaires dans les régions d'intérêt de l'écoulement, et, d'autre part, un coût de calcul abordable en activant le mode RANS lorsque la résolution LES n'est pas nécessaire ou trop coûteuse, notamment en paroi. L'objectif industriel pour EDF est d'utiliser ces méthodes pour estimer les efforts instationnaires qui s'exercent sur certains gros composants (GMPP) des réacteurs à eau pressurisée.En premier lieu, une nouvelle formulation du modèle hybride HTLES (Hybrid Temporal Large-Eddy Simulation) est développée, dans le but d'améliorer ses fondations théoriques, en utilisant le critère de H-Equivalence. L'intérêt de ce modèle réside dans l'utilisation du filtrage temporel pour contrôler la répartition d'énergie entre les échelles résolues et modélisées, permettant de garantir la consistance entre les opérateurs RANS et LES. L'approche hybride est appliquée à différents modèles de fermeture RANS, et la calibration est effectuée sur la décroissance d'une turbulence homogène isotrope. De plus, des développements analytiques similaires permettent de proposer, pour la première fois, un modèle hybride fondé sur une modification d'échelle dans une formulation RANS qui tend explicitement vers un modèle LES préexistant.Le contrôle de la transition RANS-LES dans les régions de proche paroi est une problématique majeure de cette thèse. Afin d'améliorer le comportement du modèle HTLES, une fonction de protection double (dépendante à la fois de paramètres physiques et de critères liés aux maillages) et une contrainte de consistance interne sont proposées pour imposer le mode RANS en paroi lorsque la résolution LES n'est pas appropriée. Le modèle amélioré est validé sur les écoulements en canal plan et sur les collinespériodiques, avec des résultats très satisfaisants et robustes vis-à-vis du raffinement du maillage. Il est de plus montré pour le cas test des collines périodiques que des fluctuations turbulentes résolues dans la zone LES pénètrent dans la région RANS de proche paroi sans être trop altérées. Cela permet de capturer correctement les basses fréquences des spectres d'énergie turbulente et de pression en paroi, ce qui s'avère décisif dans le but d'estimer les efforts instationnaires sur des composants. Finalement, la HTLES offre une méthode de résolution alternative au coût numérique réduit par rapport à un modèle LES résolu en paroi.Enfin, la thèse s'intéresse à une version zonale de la HTLES (imposant le mode RANS dans les régions où la résolution LES n'est pas nécessaire), en appliquant le ALF (Anisotropic Linear Forcing) au niveau des interfaces RANS-HTLES afin de promouvoir l'apparition de fluctuations turbulentes résolues. Cette première étude de faisabilité offre des résultats prometteurs.Résumé en.
Développement d'un modèle hybride RANS-LES pour l'étude des efforts instationnaires en paroi
A Selection of Test Cases for the Validation of Large-eddy Simulations of Turbulent Flows
Author:
Publisher:
ISBN: 9789283610724
Category : Computational fluid dynamics
Languages : en
Pages : 198
Book Description
Publisher:
ISBN: 9789283610724
Category : Computational fluid dynamics
Languages : en
Pages : 198
Book Description
ICREEC 2019
Author: Ahmed Belasri
Publisher: Springer Nature
ISBN: 9811554447
Category : Technology & Engineering
Languages : en
Pages : 659
Book Description
This book highlights peer reviewed articles from the 1st International Conference on Renewable Energy and Energy Conversion, ICREEC 2019, held at Oran in Algeria. It presents recent advances, brings together researchers and professionals in the area and presents a platform to exchange ideas and establish opportunities for a sustainable future. Topics covered in this proceedings, but not limited to, are photovoltaic systems, bioenergy, laser and plasma technology, fluid and flow for energy, software for energy and impact of energy on the environment.
Publisher: Springer Nature
ISBN: 9811554447
Category : Technology & Engineering
Languages : en
Pages : 659
Book Description
This book highlights peer reviewed articles from the 1st International Conference on Renewable Energy and Energy Conversion, ICREEC 2019, held at Oran in Algeria. It presents recent advances, brings together researchers and professionals in the area and presents a platform to exchange ideas and establish opportunities for a sustainable future. Topics covered in this proceedings, but not limited to, are photovoltaic systems, bioenergy, laser and plasma technology, fluid and flow for energy, software for energy and impact of energy on the environment.
Acoustics, Aeroacoustics and Vibrations
Author: Fabien Anselmet
Publisher: John Wiley & Sons
ISBN: 1119178398
Category : Technology & Engineering
Languages : en
Pages : 529
Book Description
This didactic book presents the main elements of acoustics, aeroacoustics and vibrations. Illustrated with numerous concrete examples linked to solid and fluid continua, Acoustics, Aeroacoustics and Vibrations proposes a selection of applications encountered in the three fields, whether in room acoustics, transport, energy production systems or environmental problems. Theoretical approaches enable us to analyze the different processes in play. Typical results, mostly from numerical simulations, are used to illustrate the main phenomena (fluid acoustics, radiation, diffraction, vibroacoustics, etc.).
Publisher: John Wiley & Sons
ISBN: 1119178398
Category : Technology & Engineering
Languages : en
Pages : 529
Book Description
This didactic book presents the main elements of acoustics, aeroacoustics and vibrations. Illustrated with numerous concrete examples linked to solid and fluid continua, Acoustics, Aeroacoustics and Vibrations proposes a selection of applications encountered in the three fields, whether in room acoustics, transport, energy production systems or environmental problems. Theoretical approaches enable us to analyze the different processes in play. Typical results, mostly from numerical simulations, are used to illustrate the main phenomena (fluid acoustics, radiation, diffraction, vibroacoustics, etc.).
A Parallel Finite Volume Algorithm for Large-eddy Simulation of Turbulent Flows
Author: Trong T. Bui
Publisher:
ISBN:
Category : Parallel computers
Languages : en
Pages : 28
Book Description
Publisher:
ISBN:
Category : Parallel computers
Languages : en
Pages : 28
Book Description
Advances in Rotorcraft Technology
Author: North Atlantic Treaty Organization. Advisory Group for Aerospace Research and Development. Flight Vehicle Integration Panel. Symposium
Publisher:
ISBN:
Category : Helicopters
Languages : en
Pages : 402
Book Description
Publisher:
ISBN:
Category : Helicopters
Languages : en
Pages : 402
Book Description
Software for Exascale Computing - SPPEXA 2016-2019
Author: Hans-Joachim Bungartz
Publisher: Springer Nature
ISBN: 3030479560
Category : Computers
Languages : en
Pages : 624
Book Description
This open access book summarizes the research done and results obtained in the second funding phase of the Priority Program 1648 "Software for Exascale Computing" (SPPEXA) of the German Research Foundation (DFG) presented at the SPPEXA Symposium in Dresden during October 21-23, 2019. In that respect, it both represents a continuation of Vol. 113 in Springer’s series Lecture Notes in Computational Science and Engineering, the corresponding report of SPPEXA’s first funding phase, and provides an overview of SPPEXA’s contributions towards exascale computing in today's sumpercomputer technology. The individual chapters address one or more of the research directions (1) computational algorithms, (2) system software, (3) application software, (4) data management and exploration, (5) programming, and (6) software tools. The book has an interdisciplinary appeal: scholars from computational sub-fields in computer science, mathematics, physics, or engineering will find it of particular interest.
Publisher: Springer Nature
ISBN: 3030479560
Category : Computers
Languages : en
Pages : 624
Book Description
This open access book summarizes the research done and results obtained in the second funding phase of the Priority Program 1648 "Software for Exascale Computing" (SPPEXA) of the German Research Foundation (DFG) presented at the SPPEXA Symposium in Dresden during October 21-23, 2019. In that respect, it both represents a continuation of Vol. 113 in Springer’s series Lecture Notes in Computational Science and Engineering, the corresponding report of SPPEXA’s first funding phase, and provides an overview of SPPEXA’s contributions towards exascale computing in today's sumpercomputer technology. The individual chapters address one or more of the research directions (1) computational algorithms, (2) system software, (3) application software, (4) data management and exploration, (5) programming, and (6) software tools. The book has an interdisciplinary appeal: scholars from computational sub-fields in computer science, mathematics, physics, or engineering will find it of particular interest.
Advances in Hydroinformatics
Author: Philippe Gourbesville
Publisher: Springer
ISBN: 9812876154
Category : Science
Languages : en
Pages : 616
Book Description
This book is a collection of extended papers based on presentations given during the SIMHYDRO 2014 conference, held in Sophia Antipolis in June 2014. It focuses on the modeling and simulation of fast hydraulic transients, on 3D modeling, and on uncertainties and multiphase flows. The book explores both the limitations and performance of current models and presents the latest developments based on new numerical schemes, high-performance computing, multiphysics and multiscale methods, and better interaction with field or scale model data. It addresses the interests of practitioners, stakeholders, researchers and engineers active in this field.
Publisher: Springer
ISBN: 9812876154
Category : Science
Languages : en
Pages : 616
Book Description
This book is a collection of extended papers based on presentations given during the SIMHYDRO 2014 conference, held in Sophia Antipolis in June 2014. It focuses on the modeling and simulation of fast hydraulic transients, on 3D modeling, and on uncertainties and multiphase flows. The book explores both the limitations and performance of current models and presents the latest developments based on new numerical schemes, high-performance computing, multiphysics and multiscale methods, and better interaction with field or scale model data. It addresses the interests of practitioners, stakeholders, researchers and engineers active in this field.
Satellite Situation Report
Author:
Publisher:
ISBN:
Category : Artificial satellites
Languages : en
Pages : 52
Book Description
Publisher:
ISBN:
Category : Artificial satellites
Languages : en
Pages : 52
Book Description
Aerodynamics of Road Vehicles
Author: Wolf-Heinrich Hucho
Publisher: Elsevier
ISBN: 1483102076
Category : Technology & Engineering
Languages : en
Pages : 577
Book Description
Aerodynamics of Road Vehicles details the aerodynamics of passenger cars, commercial vehicles, sports cars, and race cars; their external flow field; as well as their internal flow field. The book, after giving an introduction to automobile aerodynamics and some fundamentals of fluid mechanics, covers topics such as the performance and aerodynamics of different kinds of vehicles, as well as test techniques for their aerodynamics. The book also covers other concepts related to automobiles such as cooling systems and ventilations for vehicles. The text is recommended for mechanical engineers and phycisists in the automobile industry who would like to understand more about aerodynamics of motor vehicles and its importance on the field of road safety and automobile production.
Publisher: Elsevier
ISBN: 1483102076
Category : Technology & Engineering
Languages : en
Pages : 577
Book Description
Aerodynamics of Road Vehicles details the aerodynamics of passenger cars, commercial vehicles, sports cars, and race cars; their external flow field; as well as their internal flow field. The book, after giving an introduction to automobile aerodynamics and some fundamentals of fluid mechanics, covers topics such as the performance and aerodynamics of different kinds of vehicles, as well as test techniques for their aerodynamics. The book also covers other concepts related to automobiles such as cooling systems and ventilations for vehicles. The text is recommended for mechanical engineers and phycisists in the automobile industry who would like to understand more about aerodynamics of motor vehicles and its importance on the field of road safety and automobile production.