Download or read book Computational Fluid Dynamics CFD Simulation of a Gas Solid Fluidized Bed Residence Time Validation Study written by Baru Debtera and published by GRIN Verlag. This book was released on 2021-11-29 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: Academic Paper from the year 2021 in the subject Physics - Mechanics, , language: English, abstract: In this study, numerical simulations of a gas-solid fluidized bed reactor involving a two-fluid Eulerian multiphase model and incorporating the Kinetic Theory of Granular Flow (KTGF) for the solids phase have been performed using a commercial Computational Fluid Dynamics (CFD) software. The fluidized bed setup consists of 1,5 m height and 0,2 m diameter in which a series of experiments were performed using Helium tracer to determine the Residence Time Distribution (RTD) at various normalized velocities i.e., with different degrees of gas-solids mixing. Both 2D and 3D simulations of the fluidized bed reactor are performed. The main purpose of this study is to understand the hydrodynamic behavior of a gas-solid fluidized bed reactor through a framework of Eulerian multiphase model and to analyze hydrodynamic behavior of the gas-solids mixing.
Download or read book CFD Modeling of Hydrodynamics of Fluidized Bed written by and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this project is to simulate a gas-solid fluidized by applying CFD techniques in order to investigate hydrodynamics and heat transfer phenomena. Reactor model predictions will be compared with the corresponding experimental data reported in the literature to validate the model . To simulate a gas-solid fluidized bed we need to use the multiphase flow approach . First we have to write the equations for the different flow regimes and then different CFD techniques are applied for discretization of those equations. After that a code is written for calculating the values of volume fraction, velocity and temperature.
Download or read book Multiphase Flow and Fluidization written by Dimitri Gidaspow and published by Elsevier. This book was released on 2012-12-02 with total page 489 pages. Available in PDF, EPUB and Kindle. Book excerpt: Useful as a reference for engineers in industry and as an advanced level text for graduate engineering students, Multiphase Flow and Fluidization takes the reader beyond the theoretical to demonstrate how multiphase flow equations can be used to provide applied, practical, predictive solutions to industrial fluidization problems. Written to help advance progress in the emerging science of multiphase flow, this book begins with the development of the conservation laws and moves on through kinetic theory, clarifying many physical concepts (such as particulate viscosity and solids pressure) and introducing the new dependent variable--the volume fraction of the dispersed phase. Exercises at the end of each chapterare provided for further study and lead into applications not covered in the text itself. - Treats fluidization as a branch of transport phenomena - Demonstrates how to do transient, multidimensional simulation of multiphase processes - The first book to apply kinetic theory to flow of particulates - Is the only book to discuss numerical stability of multiphase equations and whether or not such equations are well-posed - Explains the origin of bubbles and the concept of critical granular flow - Presents clearly written exercises at the end of each chapter to facilitate understanding and further study
Download or read book Computational Fluid Dynamics CFD of Chemical Processes written by Young-Il Lim and published by MDPI. This book was released on 2021-02-22 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this Special Issue, one review paper highlights the necessity of multiscale CFD, coupling micro- and macro-scales, for exchanging information at the interface of the two scales. Four research papers investigate the hydrodynamics, heat transfer, and chemical reactions of various processes using Eulerian CFD modeling. CFD models are attractive for industrial applications. However, substantial efforts in physical modeling and numerical implementation are still required before their widespread implementation.
Download or read book CFD Simulation of Hydrodynamics of Three Phase Fluidized Bed written by and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The gas-liquid-solid fluidized bed has emerged in recent years as one of the most promising devices for three-phase operation. Such a device is of considerable industrial importance as evident from its wide application in chemical, refining, petrochemical, biochemical processing, pharmaceutical and food industries. Selection and design is one of the main parameter in the performance of three phase system. Success is dependent on the effective contact between the phases. Even though a large number of experimental studies have been done in different process parameters and physical properties, the complex hydrodynamics of three phase fluidized bed reactors are not well understood due to complicated phenomena such as particle- article, liquid- article and particle- ubble interactions. For this reason, computational fluid dynamics (CFD) has been promoted as a useful tool for understanding multiphase reactors for precise design and scale up. In the present work three different configuration of cylindrical column has been taken for studying co-current gas-liquid-solid fluidization with the help of commercial CFD codes as FLUENT. The main focus for analyzing the results is on the column with 1.88 m height and diameter of 0.1 m containing solid particles as glass beads of size 2.18 mm and 4.05 mm. In the present study of three phase fluidized simulation the hydrodynamic parameters investigated includes phase hold up, velocity profiles of all phases, bed expansion, bed voidage, static pressure drop, frictional pressure drop at wall, and energy flows. The operating variables varied includes liquid and air inlet velocity, initial solid static bed height and particle size. The dynamic characteristics obtained from CFD simulation have been validated with the experimental results and a good agreement has been observed. Eulerian-Eulerian granular multiphase flow approach is capable of predicting the overall performance of gas- iquid- olid fluidized bed. The expanded bed height is s.
Download or read book CFD Modeling of Complex Chemical Processes written by Li Xi and published by MDPI. This book was released on 2021-09-01 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: Computational fluid dynamics (CFD), which uses numerical analysis to predict and model complex flow behaviors and transport processes, has become a mainstream tool in engineering process research and development. Complex chemical processes often involve coupling between dynamics at vastly different length and time scales, as well as coupling of different physical models. The multiscale and multiphysics nature of those problems calls for delicate modeling approaches. This book showcases recent contributions in this field, from the development of modeling methodology to its application in supporting the design, development, and optimization of engineering processes.
Download or read book Engineering Fluid Dynamics written by Bjørn H. Hjertager and published by MDPI. This book was released on 2018-04-06 with total page 211 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a printed edition of the Special Issue "Engineering Fluid Dynamics" that was published in Energies
Download or read book Engineering Applications of Computational Fluid Dynamics written by Ku Zilati Ku Shaari and published by Springer. This book was released on 2014-11-28 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents the results of Computational Fluid Dynamics (CFD) analysis that can be used for conceptual studies of product design, detail product development, process troubleshooting. It demonstrates the benefit of CFD modeling as a cost saving, timely, safe and easy to scale-up methodology.
Download or read book Cfd Modeling of Gas Liquid Solid Fluidized Bed written by Ramesha D. K. and published by LAP Lambert Academic Publishing. This book was released on 2012-06 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gas liquid solid fluidized beds are used extensively in the refining, petrochemical, pharmaceutical, biotechnology, food and environmental industries. Some of these processes use solids whose densities are only slightly higher than the density of water. Because of the good heat and mass transfer characteristics, three-phase fluidized beds or slurry bubble columns have gained considerable importance in their application in physical, chemical, petrochemical, electrochemical and biochemical processing. The first part discusses about importance of gas-liquid-solid fluidized bed, their modes of operation, important hydrodynamic properties those have been studied either related to modeling or experimental analysis and applications of gas-liquid-solid fluidized bed. The second part gives an overview of the methodology used in CFD to solve problems relating mass, momentum and heat transfer. Also comparative study of various CFD related software is given in this section. Third part contains the details about problem description and approach used in FLUENT to get the solution. Finally results of simulation and comparison with experimental results are shown.
Download or read book Kinetic Theory of Granular Flows and Multi scale CFD Modeling for Fluidized Beds written by Yujian Sun and published by . This book was released on 2016 with total page 157 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fluidized beds are widely used in chemical industry for carrying out gas-solids reactions. Their advantages include superior heat transfer, low pressure drop compared to fixed beds, high throughput, and the ability to regenerate or reprocess the spent particles in a separate unit from the main reactor, when operated in a circulating fluidized bed mode. In spite of these desirable features, this type of gas-solids contactors also present challenges in understanding the detailed hydrodynamics, mixing and contacting pattern, as well as their effects on reactions. Design of commercial fluidized beds often requires scale-up from a smaller lab or pilot plant, but the behavior of the different scales must be linked by proper reactor models that take into account the possible changes in hydrodynamics and contacting patterns between the scales. This can be challenging because the prediction and extension of key parameters used in a model, such as axial dispersion number is usually not available, and phenomenological models for these parameters based on science are often missing. To meet these challenges, computational fluid dynamics, or CFD, can be utilized as a tool to extract the needed information by coarse-graining from the detailed hydrodynamics of the multiphase system, thus aiding in more rational design and scale-up of fluidized bed reactors. The CFD models in turn have their own parameters that need phenomenological models, which xii are easier to construct from fundamentals. Two types of simulation methods, i.e. Eulerian-Eulerian and Eulerian-Lagrangian, are investigated in this study. For the Eulerian method (also called two-fluid model, or TFM), in which the discrete solid particles are assumed as a continuous granular phase interpenetrated with the gas, the constitutive models for solids phase stress are needed. In this work, a new set of such models is developed from kinetic theory of granular flows with a new collision model. In this model, both the normal and tangential part of relative velocity between two colliding particles is damped due to inelastic collision, while the traditional model only takes into account the normal part. With this modification, the previously under-estimated dissipation rate of fluctuation energy is increased as expected. The models are implemented in OpenFOAM, an open-source CFD platform, to simulate a fluidized bed. The model improves the prediction of solids volume fraction without extra computational cost. In the Lagrangian or DEM (discrete element method) approach, the effort is motivated by Bhusarapus (2005) pioneering finding using CARPT (computer-aided radioactive particle tracking) that the traditional tracer method for measuring solids residence time distribution (RTD) cannot capture the actual residence time due to inability to distinguish the time that a particle temporarily spends out of the riser after first entry to or before last exit from the riser. By implementing the algorithm developed in this work to record separately the time that each particle actually spends in the riser, Lagrangian simulation is performed for a small circulating fluidized bed in OpenFOAM. The results clearly demonstrate the difference between RTD obtained from simulated traditional tracer method and that from the Lagrangian approach. Other information can be extracted as well such as the first passage time distribution, macromixing index, and interchange coefficient between a core region and an annular region, if using a core-annulus model. The potential capability of this CFD approach is boundless.
Download or read book Coupled CFD DEM Modeling written by Hamid Reza Norouzi and published by John Wiley & Sons. This book was released on 2016-09-14 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt: Discusses the CFD-DEM method of modeling which combines both the Discrete Element Method and Computational Fluid Dynamics to simulate fluid-particle interactions. Deals with both theoretical and practical concepts of CFD-DEM, its numerical implementation accompanied by a hands-on numerical code in FORTRAN Gives examples of industrial applications
Download or read book Essentials of Fluidization Technology written by John R. Grace and published by John Wiley & Sons. This book was released on 2020-06-15 with total page 626 pages. Available in PDF, EPUB and Kindle. Book excerpt: A concise and clear treatment of the fundamentals of fluidization, with a view to its applications in the process and energy industries.
Download or read book CFD Modeling and Simulation in Materials Processing 2016 written by Lifeng Zhang and published by John Wiley & Sons. This book was released on 2016-02-08 with total page 297 pages. Available in PDF, EPUB and Kindle. Book excerpt: This collection explores computational fluid dynamics (CFD) modeling and simulation of engineering processes, with contributions from researchers and engineers involved in the modeling of multiscale and multiphase phenomena in material processing systems. The papers cover the following processes: Iron and Steelmaking (Tundish, Casting, Converter, Blast Furnace); Microstructure Evolution; Casting with External Field Interaction; and Smelting, Degassing, Ladle Processing, Mechanical Mixing, and Ingot Casting. The collection also covers applications of CFD to engineering processes, and demonstrates how CFD can help scientists and engineers to better understand the fundamentals of engineering processes.
Download or read book Computational Fluid Dynamics Applications in Bio and Biomedical Processes written by Satya Eswari Jujjavarapu and published by Springer Nature. This book was released on 2024-01-17 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers emerging areas in novel design and their hydrodynamic properties relevant to bioreactors, environmental system, electrochemical systems, food processing and biomedical engineering. This book uses an interdisciplinary approach to provide a comprehensive prospective simulation modeling and hydrodynamic study in advanced biotechnological process and includes reviews of the most recent state of art in modeling and simulation of flows in biological process, such as CFD. Written by internationally recognized researchers in the field, each chapter provides a strong introductory section that is useful to both readers currently in the field and readers interested in learning more about these areas.
Download or read book Fast Fluidization written by and published by Academic Press. This book was released on 1994-12-23 with total page 453 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the last decade, circulating fluidization or fast fluidization has developed rapidly, superseding standard bubbling fluidization in many applications; for example, fast fluidization provides a better means forcontrolling emissions from the combustion of high-sulfur fuels and excels when used in boilers in steam plant and power stations. China initiated the study of fast fluidization in the early 1970s. Focusing on the substantial research cultivated in that country, with Kwauk at the leading edge, this latest volume in the Advances in Chemical Engineering Series is written in the context of the international state of the art and addresses some of the most vital issues surrounding this fluidization method."
Download or read book CFD Modeling and Simulation in Materials Processing 2018 written by Laurentiu Nastac and published by Springer. This book was released on 2018-01-10 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: This collection presents contributions on computational fluid dynamics (CFD) modeling and simulation of engineering processes from researchers and engineers involved in the modeling of multiscale and multiphase phenomena in material processing systems. The following processes are covered: Additive Manufacturing (Selective Laser Melting and Laser Powder Bed Fusion); Ironmaking and Steelmaking (Ladle Metallurgical Furnace, EAF, Continuous Casting, Blown Converter, Reheating Furnace, Rotary Hearth Furnace); Degassing; High Pressure Gas Atomization of Liquid Metals; Electroslag Remelting; Electrokinetic Deposition; Friction Stir Welding; Quenching; High Pressure Die Casting; Core Injection Molding; Evaporation of Metals; Investment Casting; Electromagnetic Levitation; Ingot Casting; Casting and Solidification with External Field (electromagnetic stirring and ultrasonic cavitation) Interaction and Microstructure Evolution The collection also covers applications of CFD to engineering processes, and demonstrates how CFD can help scientists and engineers to better understand the fundamentals of engineering processes.
Download or read book Modeling and Computational Fluid Dynamics Simulation of a Bubbling Fluidized Bed Process at Different Scales written by Jungkee Jang and published by . This book was released on 2012 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:
