Download or read book Visual Study of Hydrodynamics in a Two dimensional Gas solid Fluidized Bed written by Lisa Nalani Freeman and published by . This book was released on 1992 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydrodynamic effects play important roles in fluidized bed combustion processes. Since the motion of "bubbles" is an important influence on fluidized bed heat transfer, a better understanding of their behavior is necessary for improving the design of fluidized bed boilers. Using a two-dimensional bed, silica sand particles were fluidized with air at room conditions. The bubbling bed was videotaped, and both qualitative and quantitative information were gathered. Bubble characteristics such as size, rise velocity and frequency were studied while particle size and superficial gas velocity were varied. Results were compared with some existing theories and other similar research. The effect of internal surfaces at several heights in the bed was also studied. General bubble behavior agreed well with descriptions from previous research, and the expected spherical-cap bubble shape was observed. Both bubble size and rise velocity increased with particle size and with fluid velocity. Bubble frequency increased with fluid velocity, but decreased with increasing particle size and height in the bed. These results agree with previous work done using optical probes to measure bubble characteristics. Comparisons of data with empirical models showed general agreement. The presence of internal surfaces had the effect of reducing the bubble size, rise velocity, and frequency, and also of reducing the influence of changing particle size and superficial velocity on the bed behavior.
Download or read book Numerical Simulation of the Hydrodynamics of a Two dimensional Gas solid Fluidized Bed by New Finite Volume Based Finite Element Method written by Navid Famili Mohammad Hosein and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental and Computational Studies of Hydrodynamics in Three phase and Two phase Fluidized Beds written by and published by . This book was released on 1994 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of the present study was to investigate the hydrodynamics of three-phase fluidized beds, their rheology, and experimentally verify a predictive three fluid hydrodynamic model developed at the Illinois Institute of Technology, Chicago. The recent reviews show that there exist no such models in the literature. The IIT hydrodynamic model computes the phase velocities and the volume fractions of gas, liquid, and particulate phases. Model verification involves a comparison of these computed velocities and volume fractions to experimental values. In this thesis, a three fluid model is presented. The input into the model can be particulate viscosities either measured with a Brookfield viscometer or derived using the mathematical techniques of kinetic theory of granular flows pioneered by Savage and others. The computer simulation of a three-phase fluidized bed in an asymmetric mode qualitatively predicts the gas, liquid and solid hold-ups (volume fractions) and flow patterns in the industrially important churn-turbulent (bubbly coalesced) regimes. The computations in a fluidized bed with a symmetric distributor incorrectly showed no bubble coalescence. A combination of X-ray and [gamma]-ray densitometers was used to measure the solids and the liquid volume fractions in a two dimensional bed in the bubble coalesced regime. There is a good agreement between the theory for an asymmetric distributor and the experiments.
Download or read book Hydrodynamics written by Jin - Hai Zheng and published by BoD – Books on Demand. This book was released on 2012-03-14 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt: With the amazing advances of scientific research, Hydrodynamics - Theory and Application presents the engineering applications of hydrodynamics from many countries around the world. A wide range of topics are covered in this book, including the theoretical, experimental, and numerical investigations on various subjects related to hydrodynamic problems. The book consists of twelve chapters, each of which is edited separately and deals with a specific topic. The book is intended to be a useful reference to the readers who are working in this field.
Download or read book Numerical modeling of the hydrodynamics of gas fluidized beds written by Yusan Wang and published by . This book was released on 1988 with total page 187 pages. Available in PDF, EPUB and Kindle. Book excerpt: This research involves a numerical study of the hydrodynamics of gas fluidized beds. We use the continuum model, treating both gas and particles as interpenetrating continua. The motion of gas and particles is strongly coupled by the interactions between them. For simplicity, we only consider drag forces. We use MacCormack's numerical method to solve the hyperbolic like equations and successive error vector propagation method or a marching tridiagonal method to solve the elliptic equation for pressure, depending on the situation considered (i.e. boundary conditions and geometry). In order to understand the basic phenomena, we consider the propagation of a finite disturbance of sine wave shape in one dimension. The disturbance grows in amplitude and forms a voidage shock. Next, the two dimensional case is analyzed, starting from the uniform fluidization condition. A jet is introduced at the bottom and the formation of a bubble and its motion is observed. Additionally, we introduce a bubble inside the bed and observe its effect on bed hydrodynamics. We then calculate the rise velocity of the bubble and find that it compares well with empirical correlations. We also consider the two dimensional case with a rectangular obstacle. The initial condition is calculated using D'Arcy's law. We observe the particle packing on the top and the local expansion phenomenon under the obstacle as well as the interaction of a rising bubble. The numerical results for this case agree qualitatively with experimental observations reported by others.
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 Advances in Chemical Engineering written by and published by Academic Press. This book was released on 1998-08-10 with total page 433 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume is comprised of reviews to inform the chemical engineering community about important developments in science and technology, and to serve as starting points for further advances. Included are chapters on chemical reactions of all sorts, combustion synthesis, fluid dynamics and the analysis and design of chemical reactors, and industrial cases in environmental engineering.
Download or read book Hydrodynamics of a Two dimensional Gas liquid Packed Bed written by Nicholas Scott Martino and published by . This book was released on 2002 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigation on a Gas solid Fluidized Bed Hydrodynamics Using a Non intrusive Technology to Visualize Flow Field written by Md. Rashedul Hasan Sarker and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Two dimensional Flow Modeling written by Robert C. MacArthur and published by . This book was released on 1982 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental Study of the Hydrodynamics and Cluster Formation in a Circulating Fluidized Bed written by and published by . This book was released on 1991 with total page 127 pages. Available in PDF, EPUB and Kindle. Book excerpt: A novel non-invasive gas-solid flow measuring technique being developed and tested for studying the hydrodynamics inside the riser of a Circulating Fluidized Bed (CFB). First of the two aims of the overall program, namely, design, development and testing of the technique to characterize the particle and gas velocities in two-phase flows was accomplished in the past year. The fringe-model'' laser Doppler anemometry concept has been modified and extended by using particles coated with a fluorescent dye and introducing a narrow band pass filter in the receiving optics. The technique permits optical discrimination between the scattered light (laser wavelength from undyed particles) and the fluorescence emission (longer wavelength). Results from extensive testing of various dye-solvent combinations, counter processor settings, signal-to noise optimization and subsequent flow measurements in the test section have shown that the technique can effectively discriminate between two classes of particles--the smaller seed particles for the gas phase data and the larger bed particles. Use of a two-watt Argon-Ion laser assisted in the non-intrusive probing of the gas-solid flow and in enhancing the signal-to-noise ratio. An uncertainty analysis of LDA measurements is presented. Design of the cold flow CFB model, presently under fabrication, is outlined in this report. The Plexiglas CFB model will be employed for the riser core-annular flow studies using the fluorescence-emission based laser-Doppler anemometry. The results from this study will present a unique detailed description of the complex gas-solid behavior in the CFB riser.
Download or read book Circular written by and published by . This book was released on 1989 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1971 with total page 776 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hydrodynamics of Gas liquid solid Fluidized and Semi fluidized Beds written by Hara Mohan Jena and published by . This book was released on 2009 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Energy Research Abstracts written by and published by . This book was released on 1992-10 with total page 508 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Two dimensional Hydrodynamic Calculations written by Francis Harvey Harlow and published by . This book was released on 1959 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: Previous discussions of a computing method for solving two dimensional hydrodynamic problems are here amplified and extended. Results of computations are presented for problems involving shock diffraction and refraction, surface instabilities, and viscous flow.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 892 pages. Available in PDF, EPUB and Kindle. Book excerpt:
