Simulation of Multiphase and Chemical Reactive Flows Based on Five Equation Model


Book Description

In the simulation of scramjet engines, many complex physical phenomena are involved, such as the fuel atomization, mass transition, and chemical reactions. In order to understand these complex physical phenomena, the purpose of the current thesis is to develop an in-house code for analyzing the flow structures of the scramjet engine. In this study, we first used the five-equation multiphase flow model and the Lagrangian method to reproduce the process of the fuel atomization and evaporation in a flow over side jet problem. Shock waves, recirculation zones and breakup processes of droplet particles were well captured. Comparing the results, we found that the five-equation multiphase model shows a better resolution in the shock capturing, comparing with the single phase Navier-Stokes equations. Then, we combined the five-equation multi-phase model and the single-step reaction model to simulate the formation of the cell structures in the detonation tube. The detonation waves under various operating conditions were discussed based on a single-step reaction model to model the complex reactions. Finally, a preliminary simulation of the DLR scramjet is performed. The current works have achieved satisfactory agreement compared to the experimental data no matter in reacting flow case or non-reacting flow case.




Multiphase reacting flows: modelling and simulation


Book Description

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.




Chemical Reactor Modeling


Book Description

Chemical Reactor Modeling closes the gap between Chemical Reaction Engineering and Fluid Mechanics. The second edition consists of two volumes: Volume 1: Fundamentals. Volume 2: Chemical Engineering Applications In volume 1 most of the fundamental theory is presented. A few numerical model simulation application examples are given to elucidate the link between theory and applications. In volume 2 the chemical reactor equipment to be modeled are described. Several engineering models are introduced and discussed. A survey of the frequently used numerical methods, algorithms and schemes is provided. A few practical engineering applications of the modeling tools are presented and discussed. The working principles of several experimental techniques employed in order to get data for model validation are outlined. The monograph is based on lectures regularly taught in the fourth and fifth years graduate courses in transport phenomena and chemical reactor modeling and in a post graduate course in modern reactor modeling at the Norwegian University of Science and Technology, Department of Chemical Engineering, Trondheim, Norway. The objective of the book is to present the fundamentals of the single-fluid and multi-fluid models for the analysis of single and multiphase reactive flows in chemical reactors with a chemical reactor engineering rather than mathematical bias. Organized into 13 chapters, it combines theoretical aspects and practical applications and covers some of the recent research in several areas of chemical reactor engineering. This book contains a survey of the modern literature in the field of chemical reactor modeling.




Multiphase Flow Analysis Using Population Balance Modeling


Book Description

Written by leading multiphase flow and CFD experts, this book enables engineers and researchers to understand the use of PBM and CFD frameworks. Population balance approaches can now be used in conjunction with CFD, effectively driving more efficient and effective multiphase flow processes. Engineers familiar with standard CFD software, including ANSYS-CFX and ANSYS–Fluent, will be able to use the tools and approaches presented in this book in the effective research, modeling and control of multiphase flow problems. Builds a complete understanding of the theory behind the application of population balance models and an appreciation of the scale-up of computational fluid dynamics (CFD) and population balance modeling (PBM) to a variety of engineering and industry applications in chemical, pharmaceutical, energy and petrochemical sectors The tools in this book provide the opportunity to incorporate more accurate models in the design of chemical and particulate based multiphase processes Enables readers to translate theory to practical use with CFD software




Numerical Simulation of Reactive Flow


Book Description

This new edition takes account of the explosive growth in computer technology and the greatly increased capacity for solving complex reactive-flow problems. It presents algorithms for reactive flow simulations, describes some trade-offs involved in their use, and gives guidance for building and using models of complex reactive flows.




Theory and Modeling of Dispersed Multiphase Turbulent Reacting Flows


Book Description

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.




Modeling and Simulation of Reactive Flows


Book Description

Modelling and Simulation of Reactive Flows presents information on modeling and how to numerically solve reactive flows. The book offers a distinctive approach that combines diffusion flames and geochemical flow problems, providing users with a comprehensive resource that bridges the gap for scientists, engineers, and the industry. Specifically, the book looks at the basic concepts related to reaction rates, chemical kinetics, and the development of reduced kinetic mechanisms. It considers the most common methods used in practical situations, along with equations for reactive flows, and various techniques—including flamelet, ILDM, and Redim—for jet flames and plumes, with solutions for both. In addition, the book includes techniques to accelerate the convergence of numerical simulation, and a discussion on the analysis of uncertainties with numerical results, making this a useful reference for anyone who is interested in both combustion in free flow and in porous media. Helps readers learn how to apply applications of numerical methods to simulate geochemical kinetics Presents methods on how to transform the transport equations in several coordinate systems Includes discussions of the basic concepts related to reaction rates, chemical kinetics, and the development of reduced kinetic mechanisms, including the most common methods used in practical situations Offers a distinctive approach that combines diffusion flames and geochemical flow problems




Turbulent Multiphase Flows with Heat and Mass Transfer


Book Description

Numerous industrial systems or natural environments involve multiphase flows with heat and mass transfer. The authors of this book present the physical modeling of these flows, in a unified way, which can include various physical aspects and several levels of complexity. Thermal engineering and nuclear reactors; the extraction and transport of petroleum products; diesel and rocket engines; chemical engineering reactors and fluidized beds; smoke or aerosol dispersion; landslides and avalanches − the modeling of multiphase flows with heat and mass transfer for all these situations can be developed following a common methodology. This book is devoted to the description of the mathematical bases of how to incorporate adequate physical ingredients in agreement with known experimental facts and how to make the model evolve according to the required complexity. Contents Part 1. Approach and General Equations 1. Towards a Unified Description of Multiphase Flows. 2. Instant Equations for a Piecewise Continuous Medium. 3. Description of a “Mean Multiphase Medium”. 4. Equations for the Mean Continuous Medium. Part 2. Modeling: A Single Approach Adaptable to Multiple Applications 5. The Modeling of Interphase Exchanges. 6. Modeling Turbulent Dispersion Fluxes. 7. Modeling the Mean Gas–Liquid Interface Area per Unit Volume. 8. “Large Eddy Simulation” Style Models. 9. Contribution of Thermodynamics of Irreversible Processes. 10. Experimental Methods. 11. Some Experimental Results Pertaining to Multiphase Flow Properties that Are Still Little Understood. Part 3. From Fluidized Beds to Granular Media 12. Fluidized Beds. 13. Generalizations for Granular Media. 14. Modeling of Cauchy Tensor of Sliding Contacts. 15. Modeling the Kinetic Cauchy Stress Tensor. Part 4. Studying Fluctuations and Probability Densities 16. Fluctuations of the Gas Phase in Reactive Two-Phase Media. 17. Temperature Fluctuations in Condensed Phases. 18. Study of the PDF for Velocity Fluctuations and Sizes of Parcels. About the Authors Roland Borghi is Professor Emeritus at Ecole Centrale Marseille in France and works as a consultant in the space, petrol and automobile sectors. His research activities cover fluid mechanics, combustion and flames, and multi-phase and granular flows. He was a member of the CNRS scientific committee and a laureate of the French Academy of Science. Fabien Anselmet is Professor at Ecole Centrale Marseille in France. His research activities focus on the turbulence of fluids and its varied applications in industry and in fields linked to the environment. With a unified, didactic style, this text presents tangible models of multiphase flows with heat and mass transfer with attention to various levels of complexities. It addresses thermal engineering and nuclear reactors, extraction and transport of petroleum products, diesel engines and rocket engines, chemical engineering reactors and fluidized beds, smoke or aerosol dispersion, and landslides and avalanches. Engineers, researchers, and scientists will appreciate the discussions of modeling principles, flows and granular media, and fluctuations around averages.




Computational Flow Modeling for Chemical Reactor Engineering


Book Description

The book relates the individual aspects of chemical reactor engineering and computational flow modeling in a coherent way to explain the potential of computational flow modeling for reactor engineering research and practice.




Introduction to Multiphase Flow


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.