Download or read book Second Order Turbulent Modeling Applied to Momentumless Wakes in Stratified Fluids written by W. Stephen Lewellen Milton Teske and published by . This book was released on 1973 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: The technique of second-order closure for turbulence modeling is used to treat the growth and decay of turbulence, and the generation of internal waves behind a submarine moving at constant velocity through a stratified ocean. A computer model based on the solution of five partial differential equations and approximating nine others is generated. Required model coefficients are obtained by comparison with data obtained from laboratory flows and the atmospheric surface layer. The model is verified by comparison with Naudascher's wake data in the limit of vanishing stratification; with Wu's observations in the limit of starting with a uniformly mixed region in a strongly stratified fluid; and with Hartman and Lewis's analytical predictions in the limit of a small perturbation to the ambient linear density gradient and vanishing turbulence. (Modified author abstract).

Download or read book Turbulent Wakes in a Stratified Fluid Part 1 Model Development Verification and Sensitivity to Initial Conditions written by W. S. Lewellen and published by . This book was released on 1974 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: A computational model has been developed for the turbulent wake of a body moving through a stably stratified fluid. Details of the wake growth, collapse and generation of internal waves were examined by the application of a second-order closure approach to turbulent flow developed at A.R.A.P. over the past few years. Predictions of the model have been verified by comparison with a wide variety of wake flows including wakes with no momentum, wakes with axial momentum, wakes with angular momentum, and for wakes in both stratified and unstratified fluids. A sensitivity investigation reveals that the primary variable affecting the strength of the generated internal waves is the initial Richardson number, with the first local maximum of the vertical height of the wake scaling inversely with the 1/8th power of the initial Richardson number.

Download or read book Fundamentals Of Turbulence Modelling written by Ching Jen Chen and published by CRC Press. This book was released on 1997-12-01 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: Focuses on the second-order turbulence-closure model and its applications to engineering problems. Topics include turbulent motion and the averaging process, near-wall turbulence, applications of turbulence models, and turbulent buoyant flows.

Download or read book Handbook of Turbulence written by Walter Frost and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 511 pages. Available in PDF, EPUB and Kindle. Book excerpt: Turbulence takes place in practically all flow situations that occur naturally or in modern technological systems. Therefore, considerable effort is being expended in an attempt to understand this very complex physical phenome non and to develop both empirical and mathematical models for its description. Such numerical and analytical computational schemes would allow the reliable prediction and design of turbulent flow processes to be carried out. The purpose of this book is to bring together, in a usable form, some of the fundamental concepts of turbulence along with turbulence models and experimental techniques. It is hoped that these have "general applicability" in current engineering design. The phrase "general applicabil ity" is highlighted because the theory of turbulence is still so much in a formative stage that completely general analyses are not available now, nor will they be available in the immediate future. The concepts and models described herein represent the state-of-the art methods that are now being used to give answers to turbulent flow problems. As in all turbulent flow analysis, the methods are a blend of analytical and empirical input, and the reader should be cognizant of the simplification and restrictions imposed upon the methods when applyingthem to physical situations different from those for which they have been developed.

Download or read book Turbulence Models and Their Application in Hydraulics written by Wolfgang Rodi and published by CRC Press. This book was released on 1993-01-01 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an introduction to the subject of turbulence modelling in a form easy to understand for anybody with a basic background in fluid mechanics, and it summarizes the present state of the art. Individual models are described and examined for the merits and demerits which range from the simple Prandtl mixing length theory to complex second order closure schemes.

Download or read book Computational Science and High Performance Computing III written by Egon Krause and published by Springer Science & Business Media. This book was released on 2008-10-12 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains 18 contributions to the Third Russian-German Advanced Research Workshop on Computational Science and High Performance Computing presented in July 2007 at Novosibirsk, Russia. The workshop was organized jointly by the High Performance Computing Center Stuttgart (HLRS) and the Institute of Computational Technologies of the Siberian Branch of the Russian Academy of Sciences (ICT SB RAS) The contributions range from computer science, mathematics and high performance computing to applications in mechanical and aerospace engineering. They show a wealth of theoretical work and simulation experience with a potential of bringing together theoretical mathematical modelling and usage of high performance computing systems presenting the state of the art of computational technologies.

Download or read book Numerical Methods in Fluid Flow Problems 1970 1974 written by United States. National Technical Information Service and published by . This book was released on 1975 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Turbulence Models and Their Application written by Tuncer Cebeci and published by Springer Science & Business Media. This book was released on 2003-12-04 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Second Order Modeling of Boundary free Turbulent Shear Flows written by T. H. Shih and published by . This book was released on 1991 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mathematical Models and Integration Methods written by Oleg V. Kaptsov and published by Walter de Gruyter GmbH & Co KG. This book was released on 2024-09-23 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book compiles works presented at a seminar aiming to attract global experts in differential equations, mathematical modeling, and integration methods. It covers classical and contemporary integration techniques for partial differential equations, including Monge and Darboux's approaches and their extensions. Additionally, it introduces a novel theoretical model for plane turbulent flows, presents gravitational equations derived from the principle of least action, and explores symmetry-preserving conservative finite-difference schemes for hydrodynamic-type equations. Analytical solutions for Maxwell's equations in incompressible viscoelastic mediums are examined, alongside theoretical-group analysis of wake mathematical models and reduction to ordinary differential equations. The book also delves into special classes of two-dimensional ideal fluid motion and advancements in discrete orthogonal polynomial theory, showcasing rapid decay properties near interval boundaries. In conclusion, this comprehensive collection is indispensable for researchers and practitioners in applied mathematics, fluid dynamics, and computational modeling, providing valuable insights into cutting-edge methods and solutions in the field.

Download or read book Multiscale and Multiresolution Approaches in Turbulence written by Pierre Sagaut and published by Imperial College Press. This book was released on 2006 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt: This unique book gives a general unified presentation of the use of the multiscale/multiresolution approaches in the field of turbulence. The coverage ranges from statistical models developed for engineering purposes to multiresolution algorithms for the direct computation of turbulence. It provides the only available up-to-date reviews dealing with the latest and most advanced turbulence models (including LES, VLES, hybrid RANS/LES, DES) and numerical strategies. The book aims at providing the reader with a comprehensive description of modern strategies for turbulent flow simulation, ranging from turbulence modeling to the most advanced multilevel numerical methods. Sample Chapter(s). Chapter 1: A Brief Introduction to Turbulence (4,125 KB). Contents: A Brief Introduction to Turbulence; Turbulence Simulation and Scale Separation; Statistical Multiscale Modeling; Multiscale Subgrid Models: Self-Adaptivity; Structural Multiscale Subgrid Models: Small Scale Estimations; Unsteady Turbulence Simulation on Self-Adaptive Grids; Global Hybrid RANS/LES Methods; Zonal RANS/LES Methods. Readership: Researchers and engineers in academia and industry in aerospace, automotive and other aerodynamics-oriented fields; masters-level students in fluid mechanics, computational fluid dynamics and applied mathematics.

Download or read book Mathematical and Numerical Foundations of Turbulence Models and Applications written by Tomás Chacón Rebollo and published by Springer. This book was released on 2014-06-17 with total page 530 pages. Available in PDF, EPUB and Kindle. Book excerpt: With applications to climate, technology, and industry, the modeling and numerical simulation of turbulent flows are rich with history and modern relevance. The complexity of the problems that arise in the study of turbulence requires tools from various scientific disciplines, including mathematics, physics, engineering and computer science. Authored by two experts in the area with a long history of collaboration, this monograph provides a current, detailed look at several turbulence models from both the theoretical and numerical perspectives. The k-epsilon, large-eddy simulation and other models are rigorously derived and their performance is analyzed using benchmark simulations for real-world turbulent flows. Mathematical and Numerical Foundations of Turbulence Models and Applications is an ideal reference for students in applied mathematics and engineering, as well as researchers in mathematical and numerical fluid dynamics. It is also a valuable resource for advanced graduate students in fluid dynamics, engineers, physical oceanographers, meteorologists and climatologists.

Download or read book Modeling and Simulation of Turbulent Flows written by Roland Schiestel and published by John Wiley & Sons. This book was released on 2010-01-05 with total page 751 pages. Available in PDF, EPUB and Kindle. Book excerpt: This title provides the fundamental bases for developing turbulence models on rational grounds. The main different methods of approach are considered, ranging from statistical modelling at various degrees of complexity to numerical simulations of turbulence. Each of these various methods has its own specific performances and limitations, which appear to be complementary rather than competitive. After a discussion of the basic concepts, mathematical tools and methods for closure, the book considers second order closure models. Emphasis is placed upon this approach because it embodies potentials for clarifying numerous problems in turbulent shear flows. Simpler, generally older models are then presented as simplified versions of the more general second order models. The influence of extra physical parameters is also considered. Finally, the book concludes by examining large Eddy numerical simulations methods. Given the book’s comprehensive coverage, those involved in the theoretical or practical study of turbulence problems in fluids will find this a useful and informative read.

Download or read book Numerical Simulation of Collapsing Turbulent Wakes written by Alex. C. Warn-Varnas and published by . This book was released on 1979 with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt: The collapse of a partially mixed region generated by a prescribed amount of turbulence deposited on a linearly stratified ambient ocean is studied numerically. Different turbulent closures such as first and second order are used to model the turbulent stresses. The resulting equations are solved numerically in a finite-difference formalism of the primitive form of the equations in a box region several times the size of the mixed region. The resulting maximum observed mean field velocities, densities, and turbulent energies in the fluid are obtained and cross-compared for different closures and numerical methods.

Download or read book A Parallel Finite Volume Algorithm for Large eddy Simulation of Turbulent Flows written by Trong T. Bui and published by . This book was released on 1998 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book 43rd AIAA Aerospace Sciences Meeting Exhibit written by and published by . This book was released on 2005 with total page 590 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mathematical and Physical Theory of Turbulence Volume 250 written by John Cannon and published by CRC Press. This book was released on 2006-06-15 with total page 209 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although the current dynamical system approach offers several important insights into the turbulence problem, issues still remain that present challenges to conventional methodologies and concepts. These challenges call for the advancement and application of new physical concepts, mathematical modeling, and analysis techniques. Bringing together ex