Download or read book Evaporation and Heating of Laminar and Turbulent Falling Liquid Films written by Amir Faghri and published by . This book was released on 1976 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Evaporating Falling Film on Horizontal Tubes written by Philip J. P. Liu and published by . This book was released on 1975 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Modeling of Complex Heat Transfer Phenomena in Cooling Applications written by Xiaofei Hou and published by . This book was released on 2015 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multiphase and multicomponent flows are frequently encountered in the cooling applications due to combined heat transfer and phase change phenomena. Two-fluid and homogeneous mixture models are chosen to numerically study these flows in the cooling phenomena. Therefore this work is divided in two main parts. In the first part, a two-fluid model algorithm for free surface flows is presented. The two fluid model is usually used as a tool to simulate dispersed flow. With its extension, it may also be applied to large interface (separated) flow. In the second part, the homogeneous mixture model for the multicomponent flow is employed to solve evaporation problems. Finally the simulation is focused on the mixed transitional or turbulent flow with and without evaporation. In detail, this thesis consists of six chapters. The first chapter is devoted to an introduction to the two-fluid and homogeneous mixture models employed in the multiphase/multicomponent flow. The multiphase classification is explained and the previous works on the two models are reviewed. The second chapter is mainly focused on the application of the Fractional step method algorithm in the two-fluid model. In addition, the Conservative Level Set method(interface sharpening) is applied to overcome the weakness of the two-fluid model (numerical diffusion of the interface), which is often encountered in the simulations using this model. With the proposed algorithm, the two-fluid model suitable for the dispersed flow is extended to the separated flow. The homogeneous mixture model is introduced in the third chapter. As an application of this model, different evaporation cases have been tested. A hydrodynamically fully developed laminar flow in a horizontal duct is firstly studied. It is used to verify the model in a laminar flow considering constant physical properties. Water falling films are often applied to enhance the heat transfer. Therefore the second case analyzes the natural convection in a cavity with liquid film (assuming variable physical properties), and validates the falling film model. Finally, a third case is focused on mixed convective flow interacting with a water falling liquid film. The effects of heat flux on the evaporation rate and the flow structure are investigated employing numerical experiments. In the fourth chapter, the laminarization phenomena of turbulent forced flow in a vertical pipe with constant heat flux is studied. These studies validate the prediction ability of large eddy simulation in this complex situation. Afterwards additional cases in a long vertical pipe (100 times diameters) are conducted and the results are compared with the existing experimental data. Throughout the whole pipe, the flow state follows a complicated process, which includes turbulent-laminar and laminar-turbulent transitions. This problem is of great significance in industrial applications for it may result in the enhancement or impairment of heat transfer. Based on the previous verification of the model in turbulent and transitional flow, the simulation of the cooling in a uniformly heated vertical tube is conducted in the fifth chapter with an ascending flow of air and a falling film. This case also involves the transitional complex flow and boundary conditions of falling film with simultaneous heat/mass transfer. The variable factors affecting the evaporation and thermal efficiency have been analyzed. In Appendix C, as an application in engineering of the work developed within the thesis, a series of flows in a complex geometry of a refrigerator chamber without or with fins are simulated to obtain their effects on the flow distribution and mixing feature. In the last chapter, the main conclusions are summarized and the future works are listed.
Download or read book Process Analysis Design and Intensification in Microfluidics and Chemical Engineering written by Santana, Harrson Silva and published by IGI Global. This book was released on 2019-01-18 with total page 367 pages. Available in PDF, EPUB and Kindle. Book excerpt: Microfluidics represent great potential for chemical processes design, development, optimization, and chemical engineering bolsters the project design of industrial processes often found in large chemical plants. Together, microfluidics and chemical engineering can lead to a more complete and comprehensive process. Process Analysis, Design, and Intensification in Microfluidics and Chemical Engineering provides emerging research exploring the theoretical and practical aspects of microfluidics and its application in chemical engineering with the intention of building pathways for new processes and product developments in industrial areas. Featuring coverage on a broad range of topics such as design techniques, hydrodynamics, and numerical modelling, this book is ideally designed for engineers, chemists, microfluidics and chemical engineering companies, academicians, researchers, and students.
Download or read book Latent Heat Transfer written by G. S. H. Lock and published by . This book was released on 1996 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt: This beginning graduate text is the first comprehensive work on latent heat transfer. It covers all forms: evaporation, sublimation, melting, condensation, freezing, and deposition. Throughout the book there is emphasis on the fundamentals that apply to both industrial and environmental processes. Three introductory chapters on the history and significance of thermodynamics and fluid mechanics are followed by self-contained treatments of solidification, fluidification, condensation, evaporation and boiling. The final chapter includes worked examples. Overall, the book provides insight for graduate students in engineering.
Download or read book Computational Modeling of Falling Liquid Film Free Surface Evaporation written by Emmanuel O. Doro and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A computational model is developed to investigate fundamental flow physics and transport phenomena of evaporating wavy-laminar falling liquid films of water and black liquor. The computational model is formulated from first principles based on the conservation laws for mass, momentum, energy and species in addition to a phase transport equation for capturing interface deformation and evolution. Free surface waves are generated by monochromatic perturbation of velocity. Continuum models for interfacial evaporation define source terms for liquid vaporization and species enrichment in the conservation laws. A phenomenological crystallization model is derived to account for species depletion due to salt precipitation during black liquor falling film evaporation. Using highly resolved numerical grids on parallel computers, the computational model is implemented to analyze the dynamics of capillary separation eddies in low Reynolds number falling films, investigate the dominant mechanisms of heat transfer enhancement in falling films at moderately high Reynolds numbers and study the fundamental wave structures and wave induced transport in black liquor falling films on flat and cylindrical walls. From simulation results, a theory based on the dynamics of wavefront streamwise pressure gradient is proposed to explain interfacial waves interaction that give rise to multiple backflow regions in films dominated by solitary-capillary waves. The study shows that the mechanism of heat transfer enhancement in moderately high Reynolds number films follows from relatively lower conduction thermal resistance and higher crosswise convective transport at newly formed intermediate wavefronts. Interfacial phenomena such as wave-breaking and vapor entrainment observed in black liquor falling films is explained in terms of a mechanistic theory based on evolution of secondary instabilities and large amplitude wave force imbalances.
Download or read book Falling Liquid Films written by S. Kalliadasis and published by Springer Science & Business Media. This book was released on 2011-09-24 with total page 446 pages. Available in PDF, EPUB and Kindle. Book excerpt: Falling Liquid Films gives a detailed review of state-of-the-art theoretical, analytical and numerical methodologies, for the analysis of dissipative wave dynamics and pattern formation on the surface of a film falling down a planar inclined substrate. This prototype is an open-flow hydrodynamic instability, that represents an excellent paradigm for the study of complexity in active nonlinear media with energy supply, dissipation and dispersion. It will also be of use for a more general understanding of specific events characterizing the transition to spatio-temporal chaos and weak/dissipative turbulence. Particular emphasis is given to low-dimensional approximations for such flows through a hierarchy of modeling approaches, including equations of the boundary-layer type, averaged formulations based on weighted residuals approaches and long-wave expansions. Whenever possible the link between theory and experiment is illustrated, and, as a further bridge between the two, the development of order-of-magnitude estimates and scaling arguments is used to facilitate the understanding of basic, underlying physics. This monograph will appeal to advanced graduate students in applied mathematics, science or engineering undertaking research on interfacial fluid mechanics or studying fluid mechanics as part of their program. It will also be of use to researchers working on both applied, fundamental theoretical and experimental aspects of thin film flows, as well as engineers and technologists dealing with processes involving isothermal or heated films. This monograph is largely self-contained and no background on interfacial fluid mechanics is assumed.
Download or read book Energy Efficiency in Process Technology written by P.A. Pilavachi and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 1266 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since 1975 the Commission has been stimulating R & D work aimed at energy saving. The conference objective was to provide an international forum for the presentation and discussion of recent R & D relevant to energy efficiency, taking into account environmental aspects, in the energy intensive process industries.
Download or read book A Study of Sensible Heating and Evaporation in Free falling Liquid Films written by Jeffrey Alan Shmerler and published by . This book was released on 1986 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Falling Films in Desalination written by Henning Raach and published by Walter de Gruyter GmbH & Co KG. This book was released on 2019-08-05 with total page 323 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers the simulation of evaporating saltwater falling films with and without turbulence wires. The methods presented within can be applied to a variety of applications including the food and pharmaceutical industry, as well as in nuclear technology. This topic is ideal for researchers in chemical engineering.
Download or read book Process Heat Transfer written by Sarit K. Das and published by Alpha Science Int'l Ltd.. This book was released on 2005 with total page 750 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present text is aimed at giving the students a substantial feel of the fundamentals of heat transfer applied to process industry. Though the introduction of the material is made at the undergraduate level for a first course in Process Heat Transfer', it includes enough advanced material for postgraduate courses on Process Heat Transfer' or Heat Exchangers'. The text starts with summary of single phase heat transfer. Subsequently classification, selection and basic theory of heat transfer equipment are explained. Based on this, traditional heat exchangers as well as stirred tanks are treated in detail. Special emphasis has been laid on plate type heat exchangers. The second part introduces two-phase heat transfer followed by apparatus dealing with phase change such as condensers, evaporators, reboilers and cooling towers. Finally, recent advances in process optimization through pinch technology and energy analysis along with transient response of heat exchangers are introduced. The textbook stresses on design approach.
Download or read book Liquid Vapor Phase Change Phenomena written by Van P. Carey and published by CRC Press. This book was released on 2020-02-28 with total page 731 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the second edition of Liquid-Vapor Phase-Change Phenomena was written, research has substantially enhanced the understanding of the effects of nanostructured surfaces, effects of microchannel and nanochannel geometries, and effects of extreme wetting on liquid-vapor phase-change processes. To cover advances in these areas, the new third edition includes significant new coverage of microchannels and nanostructures, and numerous other updates. More worked examples and numerous new problems have been added, and a complete solution manual and electronic figures for classroom projection will be available for qualified adopting professors.
Download or read book Flow and Heat and Mass Transfer in Laminar and Turbulent Mist Gas Droplets Stream over a Flat Plate written by Victor I. Terekhov and published by Springer. This book was released on 2014-07-08 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book the author presents selected challenges of thermal-hydraulics modeling of two-phase flows in minichannels with change of phase. These encompass the common modeling of flow boiling and flow condensation using the same expression. Approaches to model these two respective cases show, however, that experimental data show different results to those obtained by methods of calculation of heat transfer coefficient for respective cases. Partially that can be devoted to the fact that there are non-adiabatic effects present in both types of phase change phenomena which modify the pressure drop due to friction, responsible for appropriate modelling. The modification of interface shear stresses between flow boiling and flow condensation in case of annular flow structure may be considered through incorporation of the so called blowing parameter, which differentiates between these two modes of heat transfer. On the other hand, in case of bubbly flows, the generation of bubbles also modifies the friction pressure drop by the influence of heat flux. Presented are also the results of a peculiar M-shape distribution of heat transfer coefficient specific to flow boiling in minichannels. Finally, some attention is devoted to mathematical modeling of dryout phenomena. A five equation model enabling determination of the dryout location is presented, where the mass balance equations for liquid film, droplets and gas are supplemented by momentum equations for liquid film and two-phase core.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1979 with total page 822 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fundamentals of Multiphase Heat Transfer and Flow written by Amir Faghri and published by Springer Nature. This book was released on 2019-09-13 with total page 820 pages. Available in PDF, EPUB and Kindle. Book excerpt: This textbook presents a modern treatment of fundamentals of heat and mass transfer in the context of all types of multiphase flows with possibility of phase-changes among solid, liquid and vapor. It serves equally as a textbook for undergraduate senior and graduate students in a wide variety of engineering disciplines including mechanical engineering, chemical engineering, material science and engineering, nuclear engineering, biomedical engineering, and environmental engineering. Multiphase Heat Transfer and Flow can also be used to teach contemporary and novel applications of heat and mass transfer. Concepts are reinforced with numerous examples and end-of-chapter problems. A solutions manual and PowerPoint presentation are available to instructors. While the book is designed for students, it is also very useful for practicing engineers working in technical areas related to both macro- and micro-scale systems that emphasize multiphase, multicomponent, and non-conventional geometries with coupled heat and mass transfer and phase change, with the possibility of full numerical simulation.
Download or read book Falling Films in Desalination written by Henning Raach and published by Walter de Gruyter GmbH & Co KG. This book was released on 2019-08-05 with total page 197 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers the simulation of evaporating saltwater falling films with and without turbulence wires. The methods presented within can be applied to a variety of applications including the food and pharmaceutical industry, as well as in nuclear technology. This topic is ideal for researchers in chemical engineering.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1978 with total page 1008 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.
