Download or read book Study of Transport Phenomena in Turbulent Channel Flows Using Direct Numerical Simulation and Lagrangian Scalar Tracking written by Quoc Tan Nguyen and published by . This book was released on 2016 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Turbulence Numerical Analysis Modelling and Simulation written by William Layton and published by MDPI. This book was released on 2018-05-04 with total page 229 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a printed edition of the Special Issue "Turbulence: Numerical Analysis, Modelling and Simulation" that was published in Fluids
Download or read book Study of Scalar Transport in Turbulent Flows Using Direct Numerical Simulations written by Prakash Vedula and published by . This book was released on 2001 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Lagrangian Properties of Turbulent Channel Flow written by Juan Ignacio Polanco and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Lagrangian perspective, describing a flow from the trajectories of fluid tracers, isa natural framework for studying dispersion phenomena in turbulent flows. In wall-boundedturbulence, the motion of fluid tracers is affected by mean shear and by strong inhomogeneityand anisotropy near walls. We investigate the Lagrangian properties of a turbulent channel flowusing direct numerical simulations at a moderate Reynolds number. Lagrangian accelerationstatistics are compared to particle tracking experiments performed in parallel to this work. Asin homogeneous isotropic turbulence (HIT), the acceleration components along Lagrangianpaths decorrelate over time scales representative of the smallest scales of the flow, while theacceleration norm stays correlated for much longer. The persistence of small-scale anisotropy farfrom the wall is demonstrated in the form of a non-zero cross-correlation between accelerationcomponents. As a result of the average fluxes of kinetic energy in wall turbulence, tracers initiallylocated close to the wall travel and spread over longer distances when tracked backwardsin time than forwards. The relative dispersion of tracer pairs is finally investigated. At shorttimes, pair separation is ballistic for all wall distances. As in HIT, relative dispersion is timeasymmetric, with tracers separating faster when tracked backwards in time. At longer times,mean shear dominates leading to rapid separation in the mean flow direction. A ballisticcascade model previously proposed for HIT is adapted to inhomogeneous flows.
Download or read book Transport Phenomena written by Larry A. Glasgow and published by John Wiley & Sons. This book was released on 2010-12-01 with total page 519 pages. Available in PDF, EPUB and Kindle. Book excerpt: Enables readers to apply transport phenomena principles to solve advanced problems in all areas of engineering and science This book helps readers elevate their understanding of, and their ability to apply, transport phenomena by introducing a broad range of advanced topics as well as analytical and numerical solution techniques. Readers gain the ability to solve complex problems generally not addressed in undergraduate-level courses, including nonlinear, multidimensional transport, and transient molecular and convective transport scenarios. Avoiding rote memorization, the author emphasizes a dual approach to learning in which physical understanding and problem-solving capability are developed simultaneously. Moreover, the author builds both readers' interest and knowledge by: Demonstrating that transport phenomena are pervasive, affecting every aspect of life Offering historical perspectives to enhance readers' understanding of current theory and methods Providing numerous examples drawn from a broad range of fields in the physical and life sciences and engineering Contextualizing problems in scenarios so that their rationale and significance are clear This text generally avoids the use of commercial software for problem solutions, helping readers cultivate a deeper understanding of how solutions are developed. References throughout the text promote further study and encourage the student to contemplate additional topics in transport phenomena. Transport Phenomena is written for advanced undergraduates and graduate students in chemical and mechanical engineering. Upon mastering the principles and techniques presented in this text, all readers will be better able to critically evaluate a broad range of physical phenomena, processes, and systems across many disciplines.
Download or read book Modeling Approaches and Computational Methods for Particle laden Turbulent Flows written by Shankar Subramaniam and published by Academic Press. This book was released on 2022-10-20 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt: Modelling Approaches and Computational Methods for Particle-laden Turbulent Flows introduces the principal phenomena observed in applications where turbulence in particle-laden flow is encountered while also analyzing the main methods for analyzing numerically. The book takes a practical approach, providing advice on how to select and apply the correct model or tool by drawing on the latest research. Sections provide scales of particle-laden turbulence and the principal analytical frameworks and computational approaches used to simulate particles in turbulent flow. Each chapter opens with a section on fundamental concepts and theory before describing the applications of the modelling approach or numerical method. Featuring explanations of key concepts, definitions, and fundamental physics and equations, as well as recent research advances and detailed simulation methods, this book is the ideal starting point for students new to this subject, as well as an essential reference for experienced researchers. Provides a comprehensive introduction to the phenomena of particle laden turbulent flow Explains a wide range of numerical methods, including Eulerian-Eulerian, Eulerian-Lagrange, and volume-filtered computation Describes a wide range of innovative applications of these models
Download or read book Studies in Turbulence written by Thomas B. Gatski and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 609 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Studying Turbulence Using Numerical Simulation Databases III written by Center for Turbulence Research (U.S.) and published by . This book was released on 1990 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Highly resolved Numerical Simulations of Bed load Transport in a Turbulent Open channel Flow written by Bernhard Vowinckel and published by Tudpress Verlag Der Wissenschaften Gmbh. This book was released on 2015-03-27 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt: Phase-resolving Direct Numerical Simulations of bed-load transport in a horizontal turbulent open-channel flow at small relative submergence are presented. The thesis provides a detailed study addressing the impact of the choice of collision model on the scenario of bed-load transport and presents statistical tools to identify and describe the key-mechanisms governing the fluid-particle interaction. The Double-Averaging Methodology is applied for the first time to the situation of mobile rough beds. This methodology provides a framework to convolute the data in such a way that the most prominent flow features are well described by a handy set of double-averaged (in time and space) quantities. The thesis further provides a systematic study elucidating in detail the impact of the key-parameters mobility and sediment supply on the pattern formation of large-scale particle clusters. This is done using a very large computational domain to allow bed-forms to evolve with minimal spatial constraints. It is found that a low transport rate is linked to streamwise oriented ridges, while a large sediment supply results in large-scale clusters that propagate in streamwise direction. A detailed description of fluid quantities links the developed particle patterns to the enhancement of turbulence. The large domain allows for a large number of independent erosion events, such that conditional averaging provides a very clear description of the processes involved for incipient particle motion. Furthermore, the detection of moving particle clusters as well as the investigation of their surrounding flow field is performed by an analysis using a moving frame coordinate system.
Download or read book Numerical Simulation of Turbulent Flows and Noise Generation written by Christophe Brun and published by Springer Science & Business Media. This book was released on 2009-03-07 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt: Large Eddy Simulation (LES) is a high-fidelity approach to the numerical simulation of turbulent flows. Recent developments have shown LES to be able to predict aerodynamic noise generation and propagation as well as the turbulent flow, by means of either a hybrid or a direct approach. This book is based on the results of two French/German research groups working on LES simulations in complex geometries and noise generation in turbulent flows. The results provide insights into modern prediction approaches for turbulent flows and noise generation mechanisms as well as their use for novel noise reduction concepts.
Download or read book Stochastic Lagrangian Modeling for Large Eddy Simulation of Dispersed Turbulent Two Phase Flows written by Abdallah Sofiane Berrouk and published by Bentham Science Publishers. This book was released on 2011 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding the dispersion and the deposition of inertial particles convected by turbulent flows is a domain of research of considerable industrial interest. Inertial particle transport and dispersion are encountered in a wide range of flow configurations, whether they are of industrial or environmental character. Conventional models for turbulent dispersed flows do not appear capable of meeting the growing needs of chemical, mechanical and petroleum industries in this regard and physical environment testing is prohibitive. Direct Numerical Simulation (DNS) and Large Eddy Simulation (LES) ha.
Download or read book Progress in Turbulence written by Joachim Peinke and published by Springer Science & Business Media. This book was released on 2006-05-06 with total page 235 pages. Available in PDF, EPUB and Kindle. Book excerpt: Besides turbulence, there is hardly any other scientific topic which has been considered a prominent scientific challenge for such a long time. The special interest in turbulence is not only based on it being a difficult scientific problem but also on its meaning in the technical world and our daily life. This carefully edited book comprises recent basic research as well as research related to the applications of turbulence. Therefore, both leading engineers and physicists working in the field of turbulence were invited to the iTi Conference on Turbulence held in Bad Zwischenahn, Gemany 21st - 24th of September 2003. Topics discussed include, for example, scaling laws and intermittency, thermal convection, boundary layers at large Reynolds numbers, isotropic turbulence, stochastic processes, passive and active scalars, coherent structures, numerical simulations, and related subjects.
Download or read book Studying Turbulence Using Numerical Simulation Databases V written by Center for Turbulence Research (U.S.) and published by . This book was released on 1994 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Studying Turbulence Using Numerical Simulation Databases written by Center for Turbulence Research (U.S.) and published by . This book was released on 1987 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transport and Mixing in Homogeneous and Confined Turbulent Flows written by Benjamin Kadoch (Maurice, Antoine) and published by . This book was released on 2009 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt: This subject of this thesis is the transport and mixing in turbulent flows. First, the influenceof walls on the Lagrangian transport and mixing of passive scalars in turbulenttwo-dimensional flows is investigated. Two distinct geometries are considered by meansof direct numerical simulation: a biperiodic domain and a circular domain with no-slipboundary conditions for velocity and zero flux for the scalar. A penalization method allowsto take into account boundary conditions, in a classical pseudo-spectral code. Thisstudy shows that the creation of vorticity at the wall strongly influences the Lagrangianstatistics. In particular, extreme values of Lagrangian acceleration appear in confinedflows. Moreover, mixing is more pronounced in the confined case than in the periodiccase. The numerical methods used are then extended to the case of moving obstacles.Furthermore, the role of vortical structures on mixing of passive scalars in isotropic homogeneousthree-dimensional turbulence is studied by using a technique based on nonlinearfiltering of vorticity in a wavelet basis (Coherent Vortex Extraction). This methodshows that vortical structures are responsible for the flow dynamics and mixing of thescalar. Finally, statistically stationary turbulent flows in the presence of a mean scalargradient are described using spectral and Lagrangian analysis, with a particular focus on intermittency.
Download or read book Turbulence in Open Channel Flows written by Hiroji Nakagawa and published by Routledge. This book was released on 2017-10-02 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: A review of open channel turbulence, focusing especially on certain features stemming from the presence of the free surface and the bed of a river. Part one presents the statistical theory of turbulence; Part two addresses the coherent structures in open-channel flows and boundary layers.
Download or read book Turbulent Flows written by Jean Piquet and published by Springer Science & Business Media. This book was released on 2013-04-17 with total page 767 pages. Available in PDF, EPUB and Kindle. Book excerpt: obtained are still severely limited to low Reynolds numbers (about only one decade better than direct numerical simulations), and the interpretation of such calculations for complex, curved geometries is still unclear. It is evident that a lot of work (and a very significant increase in available computing power) is required before such methods can be adopted in daily's engineering practice. I hope to l"Cport on all these topics in a near future. The book is divided into six chapters, each· chapter in subchapters, sections and subsections. The first part is introduced by Chapter 1 which summarizes the equations of fluid mechanies, it is developed in C~apters 2 to 4 devoted to the construction of turbulence models. What has been called "engineering methods" is considered in Chapter 2 where the Reynolds averaged equations al"C established and the closure problem studied (§1-3). A first detailed study of homogeneous turbulent flows follows (§4). It includes a review of available experimental data and their modeling. The eddy viscosity concept is analyzed in §5 with the l"Csulting ~alar-transport equation models such as the famous K-e model. Reynolds stl"Css models (Chapter 4) require a preliminary consideration of two-point turbulence concepts which are developed in Chapter 3 devoted to homogeneous turbulence. We review the two-point moments of velocity fields and their spectral transforms (§ 1), their general dynamics (§2) with the particular case of homogeneous, isotropie turbulence (§3) whel"C the so-called Kolmogorov's assumptions are discussed at length.
