Modeling Complex Turbulent Flows

Modeling Complex Turbulent Flows
Author: Manuel D. Salas
Publisher: Springer Science & Business Media
Total Pages: 402
Release: 1999-04-30
Genre: Science
ISBN: 9780792355908

Turbulence modeling both addresses a fundamental problem in physics, 'the last great unsolved problem of classical physics,' and has far-reaching importance in the solution of difficult practical problems from aeronautical engineering to dynamic meteorology. However, the growth of supercom puter facilities has recently caused an apparent shift in the focus of tur bulence research from modeling to direct numerical simulation (DNS) and large eddy simulation (LES). This shift in emphasis comes at a time when claims are being made in the world around us that scientific analysis itself will shortly be transformed or replaced by a more powerful 'paradigm' based on massive computations and sophisticated visualization. Although this viewpoint has not lacked ar ticulate and influential advocates, these claims can at best only be judged premature. After all, as one computational researcher lamented, 'the com puter only does what I tell it to do, and not what I want it to do. ' In turbulence research, the initial speculation that computational meth ods would replace not only model-based computations but even experimen tal measurements, have not come close to fulfillment. It is becoming clear that computational methods and model development are equal partners in turbulence research: DNS and LES remain valuable tools for suggesting and validating models, while turbulence models continue to be the preferred tool for practical computations. We believed that a symposium which would reaffirm the practical and scientific importance of turbulence modeling was both necessary and timely.

Turbulence Models and Their Application

Turbulence Models and Their Application
Author: Tuncer Cebeci
Publisher: Springer Science & Business Media
Total Pages: 140
Release: 2003-12-04
Genre: Science
ISBN: 9783540402886

After a brief review of the more popular turbulence models, the author presents and discusses accurate and efficient numerical methods for solving the boundary-layer equations with turbulence models based on algebraic formulas (mixing length, eddy viscosity) or partial-differential transport equations. A computer program employing the Cebeci-Smith model and the k-e model for obtaining the solution of two-dimensional incompressible turbulent flows without separation is discussed in detail and is presented in the accompanying CD.

Engineering Turbulence Modelling and Experiments 6

Engineering Turbulence Modelling and Experiments 6
Author: Wolfgang Rodi
Publisher: Elsevier
Total Pages: 1011
Release: 2005-05-05
Genre: Science
ISBN: 0080530958

Proceedings of the world renowned ERCOFTAC (International Symposium on Engineering Turbulence Modelling and Measurements).The proceedings include papers dealing with the following areas of turbulence:·Eddy-viscosity and second-order RANS models ·Direct and large-eddy simulations and deductions for conventional modelling ·Measurement and visualization techniques, experimental studies ·Turbulence control ·Transition and effects of curvature, rotation and buoyancy on turbulence ·Aero-acoustics ·Heat and mass transfer and chemically reacting flows ·Compressible flows, shock phenomena ·Two-phase flows ·Applications in aerospace engineering, turbomachinery and reciprocating engines, industrial aerodynamics and wind engineering, and selected chemical engineering problems Turbulence remains one of the key issues in tackling engineering flow problems. These problems are solved more and more by CFD analysis, the reliability of which depends strongly on the performance of the turbulence models employed. Successful simulation of turbulence requires the understanding of the complex physical phenomena involved and suitable models for describing the turbulent momentum, heat and mass transfer. For the understanding of turbulence phenomena, experiments are indispensable, but they are equally important for providing data for the development and testing of turbulence models and hence for CFD software validation. As in other fields of Science, in the rapidly developing discipline of turbulence, swift progress can be achieved only by keeping up to date with recent advances all over the world and by exchanging ideas with colleagues active in related fields.

Progress in Wall Turbulence: Understanding and Modeling

Progress in Wall Turbulence: Understanding and Modeling
Author: Michel Stanislas
Publisher: Springer Science & Business Media
Total Pages: 465
Release: 2010-10-26
Genre: Technology & Engineering
ISBN: 9048196035

This book will consist of a coherent collection of recent results on near wall turbulence including theory, new experiments, DNS, and modeling with RANS, LES and Low Order Dynamical Systems.

New Approaches in Modeling Multiphase Flows and Dispersion in Turbulence, Fractal Methods and Synthetic Turbulence

New Approaches in Modeling Multiphase Flows and Dispersion in Turbulence, Fractal Methods and Synthetic Turbulence
Author: F.C.G.A. Nicolleau
Publisher: Springer Science & Business Media
Total Pages: 159
Release: 2011-10-29
Genre: Technology & Engineering
ISBN: 940072506X

This book contains a collection of the main contributions from the first five workshops held by Ercoftac Special Interest Group on Synthetic Turbulence Models (SIG42. It is intended as an illustration of the sig’s activities and of the latest developments in the field. This volume investigates the use of Kinematic Simulation (KS) and other synthetic turbulence models for the particular application to environmental flows. This volume offers the best syntheses on the research status in KS, which is widely used in various domains, including Lagrangian aspects in turbulence mixing/stirring, particle dispersion/clustering, and last but not least, aeroacoustics. Flow realizations with complete spatial, and sometime spatio-temporal, dependency, are generated via superposition of random modes (mostly spatial, and sometime spatial and temporal, Fourier modes), with prescribed constraints such as: strict incompressibility (divergence-free velocity field at each point), high Reynolds energy spectrum. Recent improvements consisted in incorporating linear dynamics, for instance in rotating and/or stably-stratified flows, with possible easy generalization to MHD flows, and perhaps to plasmas. KS for channel flows have also been validated. However, the absence of "sweeping effects" in present conventional KS versions is identified as a major drawback in very different applications: inertial particle clustering as well as in aeroacoustics. Nevertheless, this issue was addressed in some reference papers, and merits to be revisited in the light of new studies in progress.

Turbulence, Coherent Structures, Dynamical Systems and Symmetry

Turbulence, Coherent Structures, Dynamical Systems and Symmetry
Author: Philip Holmes
Publisher: Cambridge University Press
Total Pages: 403
Release: 2012-02-23
Genre: Mathematics
ISBN: 1107008255

Describes methods revealing the structures and dynamics of turbulence for engineering, physical science and mathematics researchers working in fluid dynamics.

Parallel Computational Fluid Dynamics 2006

Parallel Computational Fluid Dynamics 2006
Author: Jang-Hyuk Kwon
Publisher: Elsevier
Total Pages: 320
Release: 2007-09-12
Genre: Computers
ISBN: 0080550045

The proceedings from Parallel CFD 2006 covers all aspects of parallel computings and its applications. Although CFD is one of basic tools for design procedures to produce machineries, such as automobiles, ships, aircrafts, etc., large scale parallel computing has been realized very recently, especially for the manufactures. Various applications in many areas could be experienced including acoustics, weather prediction and ocean modeling, flow control, turbine flow, fluid-structure interaction, optimization, heat transfer, hydrodynamics.- Report on current research in the field in an area which is rapidly changing - Subject is important to all interested in solving large fluid dynamics problems - Interdisciplinary activity. Contributions include scientists with a variety of backgrounds

Studies in Turbulence

Studies in Turbulence
Author: Thomas B. Gatski
Publisher: Springer Science & Business Media
Total Pages: 609
Release: 2012-12-06
Genre: Science
ISBN: 1461227925

This book contains contributions by former students, colleagues and friends of Professor John L. Lumley, on the occasion of his 60th birthday, in recognition of his enormous impact on the advancement of turbulence research. A variety of experimental, computational and theoretical topics, including turbulence modeling, direct numerical simulations, compressible turbulence, turbulent shear flows, coherent structures and the Proper Orthogonal Decomposition are contained herein. The diversity and scope of these contributions are further acknowledgment of John Lumley's wide ranging influence in the field of turbulence. The large number of contributions by the authors, many of whom were participants in The Lumley Symposium: Recent Developments in Turbulence (held at ICASE, NASA Langley Research Center on November 12 & 13, 1990), has presented us with the unique opportu nity to select a few numerical and theoretical papers for inclusion in the journal Theoretical and Computational Fluid Dynamics for which Professor Lumley serves as Editor. Extended Abstracts of these pa pers are included in this volume and are appropriately marked. The special issue of TCFD will appear this year and will serve as an additional tribute to John Lumley. As is usually the case, the efforts of others have significantly eased our tasks. We would like to express our deep appreciation to Drs. R.

Large-Eddy Simulations of Turbulence

Large-Eddy Simulations of Turbulence
Author: M. Lesieur
Publisher: Cambridge University Press
Total Pages: 240
Release: 2005-08-22
Genre: Mathematics
ISBN: 9780521781244

Large-Eddy Simulations of Turbulence is a reference for LES, direct numerical simulation and Reynolds-averaged Navier-Stokes simulation.