Download or read book Mathematical and Numerical Modeling of Turbulent Reactive Flows Using a Hybrid LES PDF Methodology written by João Marcelo Vedovoto and published by . This book was released on 2011 with total page 203 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present work is devoted to the development and implementation of a computational framework to perform numerical simulations of low Mach number turbulent reactive flows. The numerical algorithm designed for solving the transport equations relies on a fully implicit predictor-corrector integration scheme. A physically consistent constraint is retained to ensure that the velocity field is solved correctly, and the numerical solver is extensively verified using the Method of Manufactured Solutions (MMS) in both incompressible and variable-density situations. The final computational model relies on a hybrid Large Eddy Simulation / transported Probability Density Function (LES-PDF) framework. Two different turbulence closures are implemented to represent the residual stresses: the classical and the dynamic Smagorinsky models. The specification of realistic turbulent inflow boundary conditions is also addressed in details, and three distinct methodologies are implemented. The crucial importance of this issue with respect to both inert and reactive high fidelity numerical simulations is unambiguously assessed. The influence of residual sub-grid scale scalar fluctuations on the filtered chemical reaction rate is taken into account within the Lagrangian PDF framework. The corresponding PDF model makes use of a Monte Carlo technique: Stochastic Differential Equations (SDE) equivalent to the Fokker-Planck equations are solved for the progress variable of chemical reactions. With the objective of performing LES of turbulent reactive flows in complex geometries, the use of distributed computing is mandatory, and the retained domain decomposition algorithm displays very satisfactory levels of speed-up and efficiency. Finally, the capabilities of the resulting computational model are illustrated on two distinct experimental test cases: the first is a two-dimensional highly turbulent premixed flame established between two streams of fresh reactants and hot burnt gases which is stabilized in a square cross section channel flow. The second is an unconfined high velocity turbulent jet of premixed reactants stabilized by a large co-flowing stream of burned products.

Download or read book Hybrid LES PDF Methods for the Simulation of Turbulent Reactive Flows written by Venkatramanan Raman and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Consistent Hybrid Finite volume particle Method for the PDF Equations of Turbulent Reactive Flows written by Metin Muradoglu and published by . This book was released on 2000 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Computational Models for Turbulent Reacting Flows written by Rodney O. Fox and published by Cambridge University Press. This book was released on 2003-10-30 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: Table of contents

Download or read book Theory and Modeling of Dispersed Multiphase Turbulent Reacting Flows written by Lixing Zhou and published by Butterworth-Heinemann. This book was released on 2018-01-25 with total page 343 pages. Available in PDF, EPUB and Kindle. Book excerpt: Theory and Modeling of Dispersed Multiphase Turbulent Reacting Flows gives a systematic account of the fundamentals of multiphase flows, turbulent flows and combustion theory. It presents the latest advances of models and theories in the field of dispersed multiphase turbulent reacting flow, covering basic equations of multiphase turbulent reacting flows, modeling of turbulent flows, modeling of multiphase turbulent flows, modeling of turbulent combusting flows, and numerical methods for simulation of multiphase turbulent reacting flows, etc. The book is ideal for graduated students, researchers and engineers in many disciplines in power and mechanical engineering. - Provides a combination of multiphase fluid dynamics, turbulence theory and combustion theory - Covers physical phenomena, numerical modeling theory and methods, and their applications - Presents applications in a wide range of engineering facilities, such as utility and industrial furnaces, gas-turbine and rocket engines, internal combustion engines, chemical reactors, and cyclone separators, etc.

Download or read book Modelling and Simulation of Turbulent Heat Transfer written by B. Sundén and published by WIT Press. This book was released on 2005-02-21 with total page 361 pages. Available in PDF, EPUB and Kindle. Book excerpt: Providing invaluable information for both graduate researchers and R & D engineers in industry and consultancy, this book focuses on the modelling and simulation of fluid flow and thermal transport phenomena in turbulent convective flows. Its overall objective is to present state-of-the-art knowledge in order to predict turbulent heat transfer processes in fundamental and idealized flows as well as in engineering applications. The chapters, which are invited contributions from some of the most prominent scientists in this field, cover a wide range of topics and follow a unified outline and presentation to aid accessibility.

Download or read book A New Hybrid Finite volume particle Method for the PDF Equations of Turbulent Reactive Flows and Performance of Velocity Models written by Özkan Eren and published by . This book was released on 2006 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Multiphase reacting flows modelling and simulation written by Daniele L. Marchisio and published by Springer Science & Business Media. This book was released on 2007-10-16 with total page 269 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the most widely applicable modeling approaches. Chapters are organized in six groups covering from fundamentals to relevant applications. The book covers particle-based methods and also discusses Eulerian-Eulerian and Eulerian-Lagrangian techniques based on finite-volume schemes. Moreover, the possibility of modeling the poly-dispersity of the secondary phases in Eulerian-Eulerian schemes by solving the population balance equation is discussed.

Download or read book Mathematical and Numerical Foundations of Turbulence Models and Applications written by Tomás Chacón Rebollo and published by Birkhäuser. This book was released on 2014-06-17 with total page 517 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 Second Moment Closure Based Hybrid LES RANS Methods for Application in Attached and Separate Turbulent Flows written by Rajib Roy and published by . This book was released on 2017 with total page 119 pages. Available in PDF, EPUB and Kindle. Book excerpt: Numerical modeling of turbulent flows needs to be accurate yet fast and cost effective for practical applications. For flows with boundary layer separation the Large Eddy Simulation (LES) method provides accurate results but the computational cost increases fast with the Reynolds number due to the near wall resolution requirement. To alleviate the cost burden, a statistical (RANS) method can be incorporated in a LES method to build a hybrid model, which applies RANS in the near wall attached flow region (to reduce cost) and LES in the separated flow region (to increase accuracy). In this work, a novel second-moment closure based hybrid RANS-LES model is used to improve the overall accuracy. The new hybrid model coefficients are calibrated in a canonical attached flow and the model is then applied in several other attached and separated turbulent flow cases to evaluate the model performance.Y

Download or read book Statistical Theory and Modeling for Turbulent Flows written by P. A. Durbin and published by Wiley. This book was released on 2010-10-25 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: Providing a comprehensive grounding in the subject of turbulence, Statistical Theory and Modeling for Turbulent Flows develops both the physical insight and the mathematical framework needed to understand turbulent flow. Its scope enables the reader to become a knowledgeable user of turbulence models; it develops analytical tools for developers of predictive tools. Thoroughly revised and updated, this second edition includes a new fourth section covering DNS (direct numerical simulation), LES (large eddy simulation), DES (detached eddy simulation) and numerical aspects of eddy resolving simulation. In addition to its role as a guide for students, Statistical Theory and Modeling for Turbulent Flows also is a valuable reference for practicing engineers and scientists in computational and experimental fluid dynamics, who would like to broaden their understanding of fundamental issues in turbulence and how they relate to turbulence model implementation. Provides an excellent foundation to the fundamental theoretical concepts in turbulence. Features new and heavily revised material, including an entire new section on eddy resolving simulation. Includes new material on modeling laminar to turbulent transition. Written for students and practitioners in aeronautical and mechanical engineering, applied mathematics and the physical sciences. Accompanied by a website housing solutions to the problems within the book.

Download or read book Mathematical Modelling and Numerical Simulations of Chemically Reacting Turbulent Jets written by Kian Mehravaran and published by . This book was released on 2005 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Computational Fluid Dynamics written by Jiyuan Tu and published by Butterworth-Heinemann. This book was released on 2012-11-07 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt: An introduction to CFD fundamentals and using commercial CFD software to solve engineering problems, designed for the wide variety of engineering students new to CFD, and for practicing engineers learning CFD for the first time. Combining an appropriate level of mathematical background, worked examples, computer screen shots, and step by step processes, this book walks the reader through modeling and computing, as well as interpreting CFD results. The first book in the field aimed at CFD users rather than developers. New to this edition: A more comprehensive coverage of CFD techniques including discretisation via finite element and spectral element as well as finite difference and finite volume methods and multigrid method. Coverage of different approaches to CFD grid generation in order to closely match how CFD meshing is being used in industry. Additional coverage of high-pressure fluid dynamics and meshless approach to provide a broader overview of the application areas where CFD can be used. 20% new content .

Download or read book Advances in Particle finite Volume Algorithms for Turbulent Reactive Flows written by Pavel Petkov Popov and published by . This book was released on 2013 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the field of turbulent reactive flow simulations, hybrid particle/finite volume large eddy simulation/probability density function (LES/PDF) methods have been shown to be highly accurate in simulating laboratory-scale flames. Their strengths lie in the combination of the large eddy simulation procedure's ability to resolve the large, non-universal scales of turbulence, combined with the fact that probability density function models for turbulent combustion require no closure for the highly non-linear chemistry source term. This work presents advances in such hybrid particle/finite volume LES/PDF algorithms for turbulent reactive flows. New time stepping, interpolation, and coupling schemes have been proposed with the goal of reducing particle mass consistency (PMC) error (defined as the discrepancy between particle mass density and resolved finite volume density) and overall simulation error. The Multi-step Second-order Runge-Kutta (MRK2) integration scheme is an ODE integration scheme designed for reducing PMC errors when applied to discontinuous velocity fields. When applied to a discontinuous velocity field such as might be produced by a state-of-the art velocity interpolation scheme, MRK2 preserves the continuity of the Lagrangian position mapping and is second-order convergent in time, as opposed to a standard second-order Runge-Kutta scheme, which is only first-order convergent in time when applied to a discontinuous velocity field. The Direct Richardson p-th order (DRp) is a conceptually new family of SDE integration schemes which are weakly p-th order accurate in time, where p is an arbitrary positive integer. Unlike standard SDE integration schemes, which are based on matching appropriate terms in the Ito-Taylor expansion of the stochastic process, the DRp schemes work via Richardson extrapolation between the probability density functions of a set of first-order accurate Euler approximations with differing time steps. In the context of the Large Eddy Simulation/Probability Density Function (LES/PDF) code developed by the Turbulence and Combustion Group at Cornell University, a PDF to LES density coupling scheme via a transported specific volume (TSV) has been developed. While coupling approaches similar to TSV have been used previously in LES/PDF application, the present implementation is the first to allow overall second-order accuracy of the LES/PDF code in space and time. New implicit and explicit schemes for PMC error reduction schemes have been developed and tested in the context of the Sandia-Sydney bluff-body flame. Implicit PMC preservation schemes include new velocity and diffusivity interpolation algorithms, and explicit PMC error correction is achieved via a corrective velocity. While corrective velocity schemes have been used previously, the present algorithm, featuring a smoothed version of the PMC error field, is capable of maintaining the same PMC error levels with a corrective velocity of lower magnitude. Finally, the LES/PDF algorithm, developed by the Turbulence and Combustion group at Cornell, is applied to the Sandia-Sydney bluff-body flames. Comparison is made with experimental data, and the new code is in better agreement with experiment than previous simulations of the same series of flames.

Download or read book Multiscale And Multiresolution Approaches In Turbulence Les Des And Hybrid Rans les Methods Applications And Guidelines 2nd Edition written by Pierre Sagaut and published by World Scientific. This book was released on 2013-03-25 with total page 446 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book aims to provide the reader with an updated general presentation of multiscale/multiresolution approaches in turbulent flow simulations. All modern approaches (LES, hybrid RANS/LES, DES, SAS) are discussed and recast in a global comprehensive framework. Both theoretical features and practical implementation details are addressed. Some full scale applications are described, to provide the reader with relevant guidelines to facilitate a future use of these methods./a

Download or read book Mathematical Modeling of Turbulent Reactive Flows written by Mikael Mortensen and published by . This book was released on 2005 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Institute for Computational Mechanics in Propulsion Seventh Annual Report 1992 written by Charles E. Feiler and published by . This book was released on 1993 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: