Download or read book Numerical Investigation of the Gas spray Jet Interaction with Fluidized Beds written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In many industrial fluidized bed reactors, for example fluid catalytic cracking units, coaters and fluid cokers, the reactant feed is introduced into the system in the form of a gas jet or spray for different purposes. A good understanding of the interaction between the feed injection and the bed can lead to improved reactor design and operation. Despite the fact that numerical models and simulations have been used extensively to investigate fluidization processes, still little is known about the interactions of the jet/spray with fluidized beds. In this thesis, gas jets and liquid spray in several gas-solid systems are numerically studied. The Eulerian-Eulerian multi-fluid model with appropriate closure correlations is employed, and two- and three-dimensional numerical simulations are performed accordingly. The numerical simulations can be divided into two groups: two-phase (gas-solid) and three-phase (gas-liquid-solid) simulations. First, a three-dimensional numerical simulation of a single gas jet injection in a cylindrical bubbling fluidized bed is performed and is compared favorably to available experimental data and empirical correlations. After that, the injection of multiple gas jets into a small bubbling fluidized bed is numerically investigated. The influence of the secondary gas injection on the flow hydrodynamics, as well as interactions between the gas jet and the surrounding gas, solids, bubbles, and other jets is studied numerically, and the mixing of the secondary gas with the bed materials is also analyzed. To study the liquid spray in gas-solid systems, several three-phase systems of the low-flow-rate bottom spray into a flat-based spouted bed with a draft tube (DTSB), an evaporating gas-liquid spray into a uniform gas-solid crossflow, and an evaporative water spray into a hot riser are simulated, respectively. Appropriate models are chosen to describe the interactions between spray droplets and particles, as well as the inter-phase heat and mass t.
Download or read book Numerical Investigation of Gas Solid Fluidized Beds Model Development Validation and Application written by Peter Ostermeier and published by . This book was released on 2022 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 1028 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book Impact of Local Fluidized Bed Hydrodynamics on Jet bed Interaction written by Maryam Mohagheghi Dar Ranji and published by . This book was released on 2014 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt: In Fluid CokingTM or Fluid Catalytic Cracking liquid feedstocks are injected into a bed of fluidized particles. Uniform distribution of liquid feed on fluidized particles increases the yield of valuable products and improves operability in these processes. Contact between the injected liquid and the bed particles can be greatly affected by the liquid properties and local bed hydrodynamics. The impact of parameters such as liquid properties, fluidization velocity, nozzle atomization gas flowrate, nozzle location and inclination were investigated on the distribution of liquid sprayed into a fluidized bed with a reliable and fast response capacitance meter. This method was also extended to monitor the agglomerate breakup kinetics. The research showed that a liquid whose viscosity and contact angle on the surface of solid particles are similar to the liquid used in the high temperature commercial reactors provides a good simulation of liquid distribution into a fluidized bed with room temperature experiments. VarsolTM was selected for a cold simulation of Fluid CokersTM. The research also presents an innovative design of a cold model fluidized bed to investigate the impact of the velocity of particles, relative to the spray nozzle, on solidliquid contact since it varies greatly with location in actual Fluid Cokers. This design provided an inexpensive and accessible means to study the effect of the relative velocity between the spray jet and particles independently of other bed hydrodynamic characteristics. The investigation found that distribution of the injected liquid in the bed can be improved by either increasing the atomization gas flowrate or, preferably, the fluidization velocity. Study of nozzles at different locations and inclinations identified the dominant effects of bed hydrodynamics at the nozzle and jet tips on the distribution of liquid on solid particles. A model for the interactions between sprayed liquid and fluidized particles was developed for two cases: a) a stationary spray nozzle and no net motion of the fluidized solids and b) a moving nozzle with a relative velocity between spray nozzle and particles. The model results were compared with experimental results and were found to provide consistent information on the liquid concentration of the agglomerates.
Download or read book Modeling and Simulation of Turbulent Combustion written by Santanu De and published by Springer. This book was released on 2017-12-12 with total page 663 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a comprehensive review of state-of-the-art models for turbulent combustion, with special emphasis on the theory, development and applications of combustion models in practical combustion systems. It simplifies the complex multi-scale and nonlinear interaction between chemistry and turbulence to allow a broader audience to understand the modeling and numerical simulations of turbulent combustion, which remains at the forefront of research due to its industrial relevance. Further, the book provides a holistic view by covering a diverse range of basic and advanced topics—from the fundamentals of turbulence–chemistry interactions, role of high-performance computing in combustion simulations, and optimization and reduction techniques for chemical kinetics, to state-of-the-art modeling strategies for turbulent premixed and nonpremixed combustion and their applications in engineering contexts.
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 Fluid Dynamics of Turbulent Fluidized Beds for Geldart s Group B Particles written by Tom Wytrwat and published by Cuvillier Verlag. This book was released on 2022-02-15 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: An in-depth experimental study of the fluid dynamics of turbulent fluidized beds with particles of Geldart’s Group B was carried out. For this purpose, fluidization behavior was investigated in different fluidized bed plants having diameters in the range of 0.05 m to 1 m. Pressure fluctuation analysis has been used as an identification tool for the turbulent fluidized bed regime. Different fluidization conditions have been investigated by variation of the fluidized bed properties, the bed material properties, and the gas properties. Based on the measured data, a correlation predicting the transition velocity from bubbling to turbulent fluidization is introduced. To investigate the local flow structure, capacitance probe measurements have been carried out. Using this measurement technique, local solids concentrations and properties of rising bubbles have been determined and analyzed. Finally, an empiric fluid dynamic model was developed using the local measurement data. It is mainly based on capacitance probe measurements and shows high accuracy in comparison to pressure data.
Download or read book Applied mechanics reviews written by and published by . This book was released on 1948 with total page 400 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 1989 with total page 508 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Investigation of Gas Absorber Dynamics Including Axial Diffusion Effects written by Thomas Ching-Tsong Hsu and published by . This book was released on 1965 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monthly Catalog of United States Government Publications written by United States. Superintendent of Documents and published by . This book was released on 1968 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: February issue includes Appendix entitled Directory of United States Government periodicals and subscription publications; September issue includes List of depository libraries; June and December issues include semiannual index
Download or read book Proceedings of the 5th Joint ASME JSME Fluids Engineering Division Summer Conference 2007 parts A and B Symposia written by American Society of Mechanical Engineers. Fluids Engineering Division and published by . This book was released on 2007 with total page 1070 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Numerical Investigation of Radiation driven Gas Flow Above a Subliming Surface written by N. X. Rao and published by . This book was released on 1990 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Spouted and Spout Fluid Beds written by Norman Epstein and published by Cambridge University Press. This book was released on 2010-12-23 with total page 363 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the pioneering text by Mathur and Epstein over 35 years ago, much of the work on this subject has been extended or superseded, producing an enormous body of scattered literature. This edited volume unifies the subject, pulling material together and underpinning it with fundamental theory to produce the only complete, up-to-date reference on all major areas of spouted bed research and practice. With contributions from internationally renowned research groups, this book guides the reader through new developments, insights and models. The hydrodynamic and reactor models of spouted and spout-fluid beds are examined, as well as such topics as particle segregation, heat and mass transfer, mixing and scale-up. Later chapters focus on drying, particle-coating and energy-related applications based on spouted and spout-fluid beds. This is a valuable resource for chemical and mechanical engineers in research and industry.
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1999 with total page 974 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Spouted Beds written by Kishan Mather and published by Elsevier. This book was released on 2012-12-02 with total page 321 pages. Available in PDF, EPUB and Kindle. Book excerpt: Spouted Beds is a comprehensive 13-chapter book that covers the spouting phenomenon and the special features and applications of spouted beds. After briefly discussing the history and features of spouted bed compared to fluidized bed, the book deals with the fluid and solid dynamics of spouted beds. The book then gives a description of the internal geometrical structure of a stable bed, as well as the estimation of maximum spoutable bed depth. The subsequent chapters examine the attrition and heat and mass transfer in spouted beds, both between fluid and particles and within particles. The book further discusses theoretical aspects on using a spouting bed in carrying out gas phase chemical reaction. It also describes the application of spouted bed to a large variety of mechanical, thermal, diffusional, and chemical processes, whether on the bench, pilot, or commercial scale. This is followed by a discussion on the various process and equipment modifications to a standard spouted bed that have been devised to achieve specific ends. The final chapter outlines some practical hints for the benefit of the spouted bed designer and operator. This book is an ideal resource text to spouted bed designers, operators, and manufacturers.
