Direct Numerical Simulation of Multi-Phase Flows Using Extended Discontinuous Galerkin Methods PDF Download

Author: Martin Smuda
Publisher:
ISBN:
Category : Galerkin methods
Languages : en
Pages :

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Author: Leandro Damian Gryngarten
Publisher:
ISBN:
Category : Fluid dynamics
Languages : en
Pages :

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This thesis is concerned with the development of numerical techniques to simulate compressible multi-phase flows, in particular a high-accuracy numerical approach with mesh adaptivity. The Discontinuous Galerkin (DG) method was chosen as the framework for this work for being characterized for its high-order of accuracy -thus low numerical diffusion- and being compatible with mesh adaptivity due to its locality. A DG solver named DiGGIT (Discontinuous Galerkin at the Georgia Institute of Technology) has been developed and several aspects of the method have been studied. The Local Discontinuous Galerkin (LDG) method -an extension of DG for equations with high-order derivatives- was extended to solve multiphase flows using Diffused Interface Methods (DIM). This multi-phase model includes the convection of the volume fraction, which is treated as a Hamilton-Jacobi equation. This is the first study, to the author's knowledge, in which the volume fraction of a DIM is solved using the DG and the LDG methods. The formulation is independent of the Equation of State (EOS) and it can differ for each phase. This allows for a more accurate representation of the different fluids by using cubic EOSs, like the Peng-Robinson and the van der Waals models. Surface tension is modeled with a new numerical technique appropriate for LDG. Spurious oscillations due to surface tension are common to all the capturing schemes, and this new approach presents oscillations comparable in magnitude to the most common schemes. The moment limiter (ML) was generalized for non-uniform grids with hanging nodes that result from adaptive mesh refinement (AMR). The effect of characteristic, primitive, or conservative decomposition in the limiting stage was studied. The characteristic option cannot be used with the ML in multi-dimensions. In general, primitive variable decomposition is a better option than with conservative variables, particularly for multiphase flows, since the former type of decomposition reduces the numerical oscillations at material discontinuities. An additional limiting technique was introduced for DIM to preserve positivity while minimizing the numerical diffusion, which is especially important at the interface. The accuracy-preserving total variation diminishing (AP-TVD) marker for ``troubled-cell' detection, which uses an averaged-derivative basis, was modified to use the Legendre polynomial basis. Given that the latest basis is generally used for DG, the new approach avoids transforming to the averaged-derivative basis, what results in a more efficient technique.\r : Furthermore, a new error estimator was proposed to determine where to refine or coarsen the grid. This estimator was compared against other estimator used in the literature and it showed an improved performance. In order to provide equal order of accuracy in time as in space, the commonly used 3rd-order TVD Runge-Kutta (RK) scheme in the DG method was replaced in some cases by the Spectral Deferred Correction (SDC) technique. High orders in time were shown to only be required when the error in time is significant. For instance, convection-dominated compressible flows require for stability a time step much smaller than is required for accuracy, so in such cases 3rd-order TVD RK resulted to be more efficient than SDC with higher orders.\r : \r : All these new capabilities were included in DiGGIT and have provided a generalized approach capable of solving sub- and super-critical flows at sub- and super-sonic speeds, using a high-order scheme in space and time, and with AMR.\r : Canonical test cases are presented to verify and validate the formulation in one, two, and three dimensions. Finally, the solver is applied to practical applications. Shock-bubble interaction is studied and the effect of the different thermodynamic closures is assessed. Interaction between single-drops and a wall is simulated. Sticking and the onset of splashing are observed. In addition, the solver is used to simulate turbulent flows, where the high-order of accuracy clearly shows its benefits. Finally, the methodology is challenged with the simulation of a liquid jet in cross flow.

Author: Efstathios E. Michaelides
Publisher: CRC Press
ISBN: 1000790576
Category : Technology & Engineering
Languages : en
Pages : 478

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Multiphase Flows with Droplets and Particles provides an organized, pedagogical study of multiphase flows with particles and droplets. This revised edition presents new information on particle interactions, particle collisions, thermophoresis and Brownian movement, computational techniques and codes, and the treatment of irregularly shaped particles. An entire chapter is devoted to the flow of nanoparticles and applications of nanofluids. Features Discusses the modelling and analysis of nanoparticles. Covers all fundamental aspects of particle and droplet flows. Includes heat and mass transfer processes. Features new and updated sections throughout the text. Includes chapter exercises and a Solutions Manual for adopting instructors. Designed to complement a graduate course in multiphase flows, the book can also serve as a supplement in short courses for engineers or as a stand-alone reference for engineers and scientists who work in this area.

Author: Grétar Tryggvason
Publisher: Cambridge University Press
ISBN: 1139496700
Category : Computers
Languages : en
Pages : 337

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Accurately predicting the behaviour of multiphase flows is a problem of immense industrial and scientific interest. Modern computers can now study the dynamics in great detail and these simulations yield unprecedented insight. This book provides a comprehensive introduction to direct numerical simulations of multiphase flows for researchers and graduate students. After a brief overview of the context and history the authors review the governing equations. A particular emphasis is placed on the 'one-fluid' formulation where a single set of equations is used to describe the entire flow field and interface terms are included as singularity distributions. Several applications are discussed, showing how direct numerical simulations have helped researchers advance both our understanding and our ability to make predictions. The final chapter gives an overview of recent studies of flows with relatively complex physics, such as mass transfer and chemical reactions, solidification and boiling, and includes extensive references to current work.

Author: Fabian Hempert
Publisher:
ISBN: 9783843935234
Category :
Languages : en
Pages :

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Author: Zhangxin Chen
Publisher: SIAM
ISBN: 0898716063
Category : Computers
Languages : en
Pages : 551

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This book offers a fundamental and practical introduction to the use of computational methods. A thorough discussion of practical aspects of the subject is presented in a consistent manner, and the level of treatment is rigorous without being unnecessarily abstract. Each chapter ends with bibliographic information and exercises.

Author: George Yadigaroglu
Publisher: Springer
ISBN: 3319587188
Category : Technology & Engineering
Languages : en
Pages : 221

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Book Description
This book is the maiden volume in a new series devoted to lectures delivered through the annual seminars “Short Courses on Multiphase Flow,” held primarily at ETH Zurich continuously since 1984. The Zurich short courses, presented by prominent specialists in the various topics covered, have attracted a very large number of participants. This series presents fully updated and when necessary re-grouped lectures in a number of topical volumes. The collection aims at giving a condensed, critical and up-to-date view of basic knowledge on multiphase flows in relation to systems and phenomena encountered in industrial applications. The present volume covers the background of Multiphase Flows (MPF) that introduces the reader to the particular nature and complexity of multiphase flows and to basic but critical aspects of MPFs including concepts and the definition of the quantities of interest, an introduction to modelling strategies for MPFs, flow regimes, flow regime maps and tr ansition criteria. It also deals with the ubiquitous needs of the multiphase-flow modeller, namely pressure drop and phase distribution, i.e., the void fraction and the topology of the phases that determines the flow regimes.

Author: Vivek V. Ranade
Publisher: John Wiley & Sons
ISBN: 3527812040
Category : Technology & Engineering
Languages : en
Pages : 838

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Book Description
Discover the cutting-edge in multiphase flows used in the process industries In Multiphase Flows for Process Industries: Fundamentals and Applications, a team of accomplished chemical engineers delivers an insightful and complete treatment of the state-of-the-art in commonly encountered multiphase flows in the process industries. After discussing the theoretical background, experimental methods, and computational methods applicable to multiphase flows, the authors explore specific examples from the process industries. The book covers a wide range of multiphase flows, including gas-solid fluidized beds and flows with phase change. It also provides direction on how to use current advances in the field to realize efficient and optimized processes. Filling the gap between theory and practice, this unique reference also includes: A thorough introduction to multiphase flows and the process industry Practical discussions of flow regimes, lower order models and correlations, and the chronological development of mathematical models for multiphase flows Comprehensive explorations of experimental methods for characterizing multiphase flows, including flow imaging and visualization In-depth examinations of computational models for simulating multiphase flows Perfect for chemical and process engineers, Multiphase Flows for Process Industries: Fundamentals and Applications is required reading for graduate and doctoral students in the engineering sciences, as well as professionals in the chemical industry.

Author: D.W. Peaceman
Publisher: Elsevier
ISBN: 0080868606
Category : Technology & Engineering
Languages : en
Pages : 191

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Book Description
The use of numerical reservoir simulation with high-speed electronic computers has gained wide acceptance throughout the petroleum industry for making engineering studies of a wide variety of oil and gas reservoirs throughout the world. These reservoir simulators have been designed for use by reservoir engineers who possess little or no background in the numerical mathematics upon which they are based. In spite of the efforts to improve numerical methods to make reservoir simulators as reliable, efficient, and automatic as possible, the user of a simulator is faced with a myriad of decisions that have nothing to do with the problem to be solved. This book combines a review of some basic reservoir mechanics with the derivation of the differential equations that reservoir simulators are designed to solve.

Author: Andrea Alberto Mammoli
Publisher: WIT Press
ISBN: 1845645189
Category : Science
Languages : en
Pages : 345

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Book Description
Multiphase flows, which can involve compressible or incompressible linear or nonlinear, fluids, Are found in all areas of technology, at all length scales and flow regimes. In spite of their ubiquitousness, however multiphase flow continues to be one of the most challenging areas of computational mechanics and experimental methods, with numerous problems remaining unsolved to date. Because the multiphase flow problems are so complex, advanced computational and experimental methods are often required to solve the equations that describe them. The many hhallenges include modelling nonlinear fluids, modelling and tracking interfaces, dealing with multiple length scales, characterizing phase structures, and treating drop breakup and coalescence. Models must be validated, which requires the use of expensive and difficult experimental techniquess. This book presents contributions on the latest research in these techniques, presented at the sixth in a biennial series of conferences on the subject that begain in 2001. Featured topics include: Bubble and drop dynamics, Flow in porous media, Turbulent flow, Multiphase flow simulation, Image processing, Heat transfer, Interaction of gases, liquids and solids, Interface behaviour, Small scale phenomena, Atomization processes, and Liquid film behaviour.