Principles of Computational Fluid Dynamics

Author: Pieter Wesseling

Publisher: Springer Science & Business Media

ISBN: 3642051456

Category: Mathematics

Page: 644

View: 535

This up-to-date book gives an account of the present state of the art of numerical methods employed in computational fluid dynamics. The underlying numerical principles are treated in some detail, using elementary methods. The author gives many pointers to the current literature, facilitating further study. This book will become the standard reference for CFD for the next 20 years.

Numerische Simulation des Geräusches massiv abgelöster Strömung bei großer Reynoldszahl und kleiner Machzahl

Author: Knacke, Thilo

Publisher: Universitätsverlag der TU Berlin

ISBN: 3798327351

Category: Technology & Engineering

Page: 240

View: 1205

Strömungsinduzierte Geräusche stellen heute ein zunehmendes Problem dar, besonders in der Umgebung von Flughäfen. Eine flächendeckende Lärmminderung ließe sich hier in erster Linie durch konstruktive Maßnahmen zur Abschwächung der wesentlichen Schallentstehungsmechanismen am Flugzeug erzielen. Dies setzt jedoch voraus, dass verlässliche aeroakustische Vorhersagen getroffen werden können, wozu nicht nur präzise Berechnungsverfahren für die Schallausbreitung, sondern auch für das mittlere Strömungsfeld und für die aerodynamischen Geräuschquellen erforderlich sind. In der vorliegenden Arbeit wird ein im Bereich subsonischer Strömungssimulationen etabliertes, druckbasiertes 3D-Finite-Volumen-Verfahren für den Einsatz in aeroakustischen Grobstruktursimulationen weiterentwickelt. Der hier vordergründig betrachtete Strömungszustand und Kennzahlbereich ist typisch für das Entstehen von „airframe noise“, aerodynamischem Lärm, welcher primär durch die turbulente Umströmung von Fahrwerk und Hochauftriebshilfen startender oder landender Flugzeuge verursacht wird. Die Kopplung von kompressiblen Grobstruktursimulationen im Quellgebiet mit nachgeschalteten akustischen Extrapolationen ermöglicht eine Berechnung dieser Umströmungsgeräusche bis ins Fernfeld. Nach kurzer Darstellung der physikalischen Grundlagen und verschiedener Möglichkeiten zur numerischen Simulation wird das ausgewählte Verfahren im Detail analysiert und eine Schwachstelle in der zur Berechnung der Massenflüsse eingesetzten Interpolation nach Rhie & Chow identifiziert. Der Schwerpunkt der Weiterentwicklung liegt anschließend auf der sorgfältigen Herleitung einer Familie konsistenter Approximationen zur Bestimmung von Massenflüssen über Kontrollvolumengrenzflächen auf nichtversetzten Gittern. Zwei neue Varianten der Massenflussberechnung werden in das bestehende Druckkorrekturverfahren integriert. Deren Verhalten wird im Vergleich zur ursprünglichen Implementierung an einem akademischen Testfall bewertet. Es folgt eine Abstimmung von Numerik und Feinstrukturmodell am Zerfall isotroper Turbulenz und nach der Qualifizierung des verbesserten Verfahrens schließlich dessen Anwendung zur Berechnung von Strömungsgeräuschen an einer generischen Fahrwerksverstrebung und an einer 3-Komponenten-Hochauftriebskonfiguration. Die Ergebnisse dieser Simulationen weisen überwiegend eine sehr gute Übereinstimmung mit experimentell ermittelten Daten auf. Auf Basis einer aeroakustischen Analyse der hochaufgelösten Simulationsergebnisse am Vorflügel gelingt letztlich ein statistischer Nachweis für den dort dominierenden Schallentstehungsmechanismus. Flow-induced noise represents an increasing problem today, particularly in the vicinity of airports. Comprehensive aircraft noise reduction could primarily be achieved through design changes which mitigate the major noise generation mechanisms. However, such changes require reliable aeroacoustic predictions, which is only possible if appropriate numerical tools are available. These must allow the precise calculation of the sound and mean flow fields as well as the most relevant aerodynamic noise sources. In this work a pressure-based 3D finite volume method, which is already well-established in the area of subsonic flow computation, is further developed in order to enable its application for aeroacoustic large-eddy simulations. The flow state and the range of similarity parameters considered here are chosen to be representative of typical airframe noise. This is mainly caused by separated flow around deployed landing gear and high-lift devices during aircraft takeoff and landing. The coupling of compressible large-eddy simulations in the main sound source regions with subsequent acoustic extrapolations provides access to the prediction of such aerodynamic noise up to the farfield. The selected method is analysed in detail following a brief overview of the physical background and state-of-the-art numerical simulation techniques. A weak point is identified in the Rhie & Chow interpolation which is employed for the calculation of mass fluxes. Particular emphasis is then placed on the careful derivation of a family of consistent approximations for the determination of mass flux over control volume faces on co-located grids. Two new flux formulations are integrated into the existing pressure correction method. Their behaviour is validated and compared to that of the original implementation on an academic test case. Following a thorough reassessment of the balance between numerical and modelled dissipation on the decay of isotropic turbulence, the improved method is finally applied to compute the flow-induced noise around a generic two-struts configuration and around a three-component high-lift configuration. The simulation results predominantly exhibit very good agreement with experimental data. Based on highly-resolved flow field data acquired from the simulation of the high-lift system, a concise aeroacoustic analysis is offered. Statistical evidence of the dominant noise generation mechanism near a leading edge slat is provided.

Recent Advances in Computational Engineering

Proceedings of the 4th International Conference on Computational Engineering (ICCE 2017) in Darmstadt

Author: Michael Schäfer,Marek Behr,Miriam Mehl,Barbara Wohlmuth

Publisher: Springer

ISBN: 3319938916

Category: COMPUTERS

Page: N.A

View: 1987

Boundary-value problems for transonic flow

Author: Alexander G Kuz'min,Aleksandr Grigorʹevich Kuzʹmin

Publisher: John Wiley & Sons Inc

ISBN: 9780471486411

Category: Mathematics

Page: 304

View: 3901

Transonic flow occurs around moving objects as they approach and cross the sound barrier. Serious problems can occur at this point, such as shock-induced flow separation which can cause the aircraft to spin out of control. Another important practical problem is the achievement of higher aerodynamic performance of aircraft at cruise conditions, which leads to considerable fuel savings. The success in application of numerical methods for simulation of transonic flow and aircraft design depends on developments in the underlying mathematical theory. This book presents a breakthrough in the solvability analysis of boundary value problems, which makes it possible to establish convergence of finite element approximations for shock-free flow and to provide a framework for putting the existing numerical methods on a more sound basis. Also, physical aspects concerned with patterns of formation and propagation of weak shock waves are analysed. This contributes to the understanding of the extreme sensitivity of transonic flow to perturbation of freestream conditions. The developed theoretical knowledge base yields promising concepts of the airfoil design and active flow control by airfoil/wing shape modifications or suction/blowing through a perforated surface. Boundary Value Problems for Transonic Flow * Focuses on Computational Fluid Dynamics. * Addresses practical problems, such as airfoil design and flow control. * Presents developments made in the last two decades. In essence this is a much needed monograph for researchers and engineers in applied mathematics and numerical analysis applied to aerodynamics and for algorithm developers in Computational Fluid Dynamics in the aircraft industry. It gives design engineers the underlying mathematical theory necessary for developing new concepts for airfoil/wing design and flow control.

Numerische Strömungsmechanik

Author: Joel H. Ferziger,Milovan Peric

Publisher: Springer-Verlag

ISBN: 3540682287

Category: Science

Page: 509

View: 7796

Das Buch bietet einen Überblick über die numerischen Methoden zur Lösung strömungsmechanischer Probleme. Die in der Praxis meistgenutzten Methoden werden detailliert beschrieben. Behandelt werden auch fortgeschrittene Methoden, wie die Simulation von Turbulenzen und Parallel-Verarbeitung. Das Buch beschreibt die Grundlagen und Prinzipien der verschiedenen Methoden. Numerische Genauigkeit und Abschätzung sowie Fehlerreduktion werden detailliert mit vielen Beispielen behandelt. Alle Computercodes sind über den Server ftp.springer.de des Springer-Verlages erhältlich (Internet).

RAIRO.

Modélisation Mathématique Et Analyse Numérique : M2N.. Mathematical modelling and numerical analysis

Author: EDP Sciences

Publisher: N.A

ISBN: N.A

Category: Numerical analysis

Page: N.A

View: 2707

Slow Viscous Flow

Author: William E. Langlois,Michel O. Deville

Publisher: Springer Science & Business Media

ISBN: 3319038354

Category: Mathematics

Page: 324

View: 8994

Leonardo wrote, “Mechanics is the paradise of the mathematical sciences, because by means of it one comes to the fruits of mathematics”; replace “Mechanics” by “Fluid mechanics” and here we are. - From the Preface to the Second Edition Although the exponential growth of computer power has advanced the importance of simulations and visualization tools for elaborating new models, designs and technologies, the discipline of fluid mechanics is still large, and turbulence in flows remains a challenging problem in classical physics. Like its predecessor, the revised and expanded Second Edition of this book addresses the basic principles of fluid mechanics and solves fluid flow problems where viscous effects are the dominant physical phenomena. Much progress has occurred in the half a century that has passed since the edition of 1964. As predicted, aspects of hydrodynamics once considered offbeat have risen to importance. For example, the authors have worked on problems where variations in viscosity and surface tension cannot be ignored. The advent of nanotechnology has broadened interest in the hydrodynamics of thin films, and hydromagnetic effects and radiative heat transfer are routinely encountered in materials processing. This monograph develops the basic equations, in the three most important coordinate systems, in a way that makes it easy to incorporate these phenomena into the theory. The book originally described by Prof. Langlois as "a monograph on theoretical hydrodynamics, written in the language of applied mathematics" offers much new coverage including the second principle of thermodynamics, the Boussinesq approximation, time dependent flows, Marangoni convection, Kovasznay flow, plane periodic solutions, Hele-Shaw cells, Stokeslets, rotlets, finite element methods, Wannier flow, corner eddies, and analysis of the Stokes operator.

Mathematical Reviews

Author: N.A

Publisher: N.A

ISBN: N.A

Category: Mathematics

Page: N.A

View: 9992

Geometric Continuum Mechanics and Induced Beam Theories

Author: Simon R. Eugster

Publisher: Springer

ISBN: 3319164953

Category: Technology & Engineering

Page: 146

View: 5500

This research monograph discusses novel approaches to geometric continuum mechanics and introduces beams as constraint continuous bodies. In the coordinate free and metric independent geometric formulation of continuum mechanics as well as for beam theories, the principle of virtual work serves as the fundamental principle of mechanics. Based on the perception of analytical mechanics that forces of a mechanical system are defined as dual quantities to the kinematical description, the virtual work approach is a systematic way to treat arbitrary mechanical systems. Whereas this methodology is very convenient to formulate induced beam theories, it is essential in geometric continuum mechanics when the assumptions on the physical space are relaxed and the space is modeled as a smooth manifold. The book addresses researcher and graduate students in engineering and mathematics interested in recent developments of a geometric formulation of continuum mechanics and a hierarchical development of induced beam theories.

Optimization and Computational Fluid Dynamics

Author: Dominique Thévenin,Gábor Janiga

Publisher: Springer Science & Business Media

ISBN: 9783540721536

Category: Technology & Engineering

Page: 294

View: 9779

The numerical optimization of practical applications has been an issue of major importance for the last 10 years. It allows us to explore reliable non-trivial configurations, differing widely from all known solutions. The purpose of this book is to introduce the state-of-the-art concerning this issue and many complementary applications are presented.

Angewandte Mathematik: Body and Soul

Band 2: Integrale und Geometrie in IRn

Author: Kenneth Eriksson,Donald Estep,Claes Johnson

Publisher: Springer-Verlag

ISBN: 3540269509

Category: Mathematics

Page: 362

View: 7995

"Angewandte Mathematik: Body & Soul" ist ein neuer Grundkurs in der Mathematikausbildung für Studienanfänger in den Naturwissenschaften, der Technik, und der Mathematik, der an der Chalmers Tekniska Högskola in Göteborg entwickelt wurde. Er besteht aus drei Bänden sowie Computer-Software. Das Projekt ist begründet in der Computerrevolution, die ihrerseits völlig neue Möglichkeiten des wissenschaftlichen Rechnens in der Mathematik, den Naturwissenschaften und im Ingenieurwesen eröffnet hat. Es besteht aus einer Synthese der mathematischen Analysis (Soul) mit der numerischen Berechnung (Body) sowie den Anwendungen. Die Bände I-III geben eine moderne Version der Analysis und der linearen Algebra wieder, einschließlich konstruktiver numerischer Techniken und Anwendungen, zugeschnitten auf Anfängerprogramme im Maschinenbau und den Naturwissenschaften. Weitere Bände behandeln Themen wie z.B. dynamische Systeme, Strömungsdynamik, Festkörpermechanik und Elektromagnetismus. Dieser Band entwickelt das Riemann-Integral, um eine Funktion zu einer gegebenen Ableitung zu bestimmen. Darauf aufbauend werden Differentialgleichungen und Anfangswertprobleme mit einer Vielzahl anschaulicher Anwendungen behandelt. Die lineare Algebra wird auf n-dimensionale Räume verallgemeinert, wobei wiederum dem praktischen Umgang und numerischen Lösungstechniken besonderer Platz eingeräumt wird. Die Autoren sind führende Experten im Gebiet des wissenschaftlichen Rechnens und haben schon mehrere erfolgreiche Bücher geschrieben. "[......] Oh, by the way, I suggest immediate purchase of all three volumes!" The Mathematical Association of America Online, 7.7.04

Fundamentals of Computational Fluid Dynamics

Author: H. Lomax,Thomas H. Pulliam,David W. Zingg

Publisher: Springer Science & Business Media

ISBN: 3662046547

Category: Science

Page: 250

View: 5359

The chosen semi-discrete approach of a reduction procedure of partial differential equations to ordinary differential equations and finally to difference equations gives the book its distinctiveness and provides a sound basis for a deep understanding of the fundamental concepts in computational fluid dynamics.

Numerical Modeling in Materials Science and Engineering

Author: Michel Rappaz,Michel Bellet,Michel Deville

Publisher: Springer Science & Business Media

ISBN: 3642118216

Category: Technology & Engineering

Page: 540

View: 1188

Computing application to materials science is one of the fastest-growing research areas. This book introduces the concepts and methodologies related to the modeling of the complex phenomena occurring in materials processing. It is intended for undergraduate and graduate students in materials science and engineering, mechanical engineering and physics, and for engineering professionals or researchers.

Computational Modeling in Biological Fluid Dynamics

Author: Lisa J. Fauci,Shay Gueron,Institute of Mathematics and Its Applications

Publisher: Springer Science & Business Media

ISBN: 9780387952338

Category: Mathematics

Page: 238

View: 8174

This volume contains invited and refereed papers based upon presentations given in the IMA workshop on Computational Modeling in Biological Fluid Dynamics during January of 1999, which was part of the year-long program "Mathematics in Biology." This workshop brought together biologists, zoologists, engineers, and mathematicians working on a variety of issues in biological fluid dynamics. A unifying theme in biological fluid dynamics is the interaction of elastic boundaries with a surrounding fluid. These moving boundary problems, coupled with the equations of incompressible, viscuous fluid dynamics, pose formidable challenges to the computational scientist. In this volume, a variety of computational methods are presented, both in general terms and within the context of applications including ciliary beating, blood flow, and insect flight. Our hope is that this collection will allow others to become aware of and interested in the exciting accomplishments and challenges uncovered during this workshop.

Books in Series

Author: N.A

Publisher: N.A

ISBN: 9780835221092

Category: Monographic series

Page: 1756

View: 5338

Applied Mathematics: Body and Soul

Volume 1: Derivatives and Geometry in IR3

Author: Kenneth Eriksson,Donald Estep,Claes Johnson

Publisher: Springer Science & Business Media

ISBN: 9783540008903

Category: Mathematics

Page: 426

View: 2110

(Volume 1)

Grenzschicht-Theorie

Author: H. Schlichting,Klaus Gersten

Publisher: Springer-Verlag

ISBN: 3662075547

Category: Technology & Engineering

Page: 852

View: 3714

Die Überarbeitung für die 10. deutschsprachige Auflage von Hermann Schlichtings Standardwerk wurde wiederum von Klaus Gersten geleitet, der schon die umfassende Neuformulierung der 9. Auflage vorgenommen hatte. Es wurden durchgängig Aktualisierungen vorgenommen, aber auch das Kapitel 15 von Herbert Oertel jr. neu bearbeitet. Das Buch gibt einen umfassenden Überblick über den Einsatz der Grenzschicht-Theorie in allen Bereichen der Strömungsmechanik. Dabei liegt der Schwerpunkt bei den Umströmungen von Körpern (z.B. Flugzeugaerodynamik). Das Buch wird wieder den Studenten der Strömungsmechanik wie auch Industrie-Ingenieuren ein unverzichtbarer Partner unerschöpflicher Informationen sein.

Robust Numerical Methods for Singularly Perturbed Differential Equations

Convection-Diffusion-Reaction and Flow Problems

Author: Hans-Görg Roos,Martin Stynes,Lutz Tobiska

Publisher: Springer Science & Business Media

ISBN: 3540344675

Category: Mathematics

Page: 604

View: 7156

This new edition incorporates new developments in numerical methods for singularly perturbed differential equations, focusing on linear convection-diffusion equations and on nonlinear flow problems that appear in computational fluid dynamics.