Heat And Mass Transfer In Drying Of Porous Media

Heat and Mass Transfer in Drying of Porous Media offers a comprehensive review of heat and mass transfer phenomena and mechanisms in drying of porous materials. It covers pore-scale and macro-scale models, includes various drying technologies, and discusses the drying dynamics of fibrous porous material, colloidal porous media and size-distributed particle system. Providing guidelines for mathematical modeling and design as well as optimization of drying of porous material, this reference offers useful information for researchers and students as well as engineers in drying technology, food processes, applied energy, mechanical, and chemical engineering.

This book, "Heat and Mass Transfer in Porous Media", presents a set of new developments in the field of basic and applied research work on the physical and chemical aspects of heat and mass transfer phenomena in a porous medium domain, as well as related material properties and their measurements. The book contents include both theoretical and experimental developments, providing a self-contained major reference that is appealing to both the scientists and the engineers. At the same time, these topics will encounter of a variety of scientific and engineering disciplines, such as chemical, civil, agricultural, mechanical engineering, etc. The book is divided in several chapters that intend to be a short monograph in which the authors summarize the current state of knowledge for benefit of professionals.

This book provides recent advances in research on drying of particulate and porous materials. It is based on a selection of papers presented at the XI Polish Drying Symposium 2005. The contributions cover theoretical, as well as experimental and modeling research on heat and mass transfer processes during drying of porous material and fluidized beds. The book is a pioneering contribution to the science and technology of drying of particulate solids.

Most conventional dryers use random heating to dry diverse materials without considering their thermal sensitivity and energy requirements for drying. Eventually, excess energy consumption is necessary to attain a low-quality dried product. Proper heat and mass transfer modelling prior to designing a drying system for selected food materials can overcome these problems. Heat and Mass Transfer Modelling During Drying: Empirical to Multiscale Approaches extensively discusses the issue of predicting energy consumption in terms of heat and mass transfer simulation. A comprehensive mathematical model can help provide proper insight into the underlying transport phenomena within the materials during drying. However, drying of porous materials such as food is one of the most complex problems in the engineering field that is also multiscale in nature. From the modelling perspective, heat and mass transfer phenomena can be predicted using empirical to multiscale modelling. However, multiscale simulation methods can provide a comprehensive understanding of the physics of drying food materials. KEY FEATURES Includes a detailed discussion on material properties that are relevant for drying phenomena Presents an in-depth discussion on the underlying physics of drying using conceptual visual content Provides appropriate formulation of mathematical modelling from empirical to multiscale approaches Offers numerical solution approaches to mathematical models Presents possible challenges of different modelling strategies and potential solutions The objective of this book is to discuss the implementation of different modelling techniques ranging from empirical to multiscale in order to understand heat and mass transfer phenomena that take place during drying of porous materials including foods, pharmaceutical products, paper, leather materials, and more.

The rapid growth of literature on convective heat and mass transfer through porous media has brought both engineering and fundamental knowledge to a new state of completeness and depth. Additionally, several new questions of fundamental merit have arisen in several areas which bear direct relation to further advancement of basic knowledge and applications in this field. For example, the growth of fundamental heat transfer data and correlations for engineering use for saturated media has now reached the point where the relations for heat transfer coefficients and flow parameters are known well enough for design purposes. Multiple flow field regimes in natural convection have been identified in several important enclosure geometries. New questions have arisen on the nature of equations being used in theoretical studies, i. e. , the Validity of Darcy assumption is being brought into question; Wall effects in high and low velocity flow fields have been found to play a role in predicting transport coefficients; The formulation of transport problems in fractured media are being investigated as both an extension of those in a homogeneous medium and for application in engineering systems in geologic media and problems on saturated media are being addressed to determine their proper formulation and solution. The long standing problem of how to adequately formulate and solve problems of multi-phase heat and mass transfer in heterogeneous media is important in the technologies of chemical reactor engineering and enhanced oil recovery.

Mass Transfer–Driven Evaporation from Capillary Porous Media offers a comprehensive review of mass transfer–driven drying processes in capillary porous media, including pore-scale and macro-scale experiments and models. It covers kinetics of drying of a single pore, pore-scale experiments and models, macro-scale experiments and models, and understanding of the continuum model from pore-scale studies. The book: Explains the detailed transport processes in porous media during drying. Introduces cutting-edge visualization experiments of drying in porous media. Describes the pore network models of drying in porous media. Discusses the continuum models of drying in porous media based on pore-scale studies. Points out future research opportunities. Aimed at researchers, students and practicing engineers, this work provides vital fundamental and applied information to those working in drying technology, food processes, applied energy, and mechanical and chemical engineering.

Although the empirical treatment of fluid flow and heat transfer in porous media is over a century old, only in the last three decades has the transport in these heterogeneous systems been addressed in detail. So far, single-phase flows in porous media have been treated or at least formulated satisfactorily, while the subject of two-phase flow and the related heat-transfer in porous media is still in its infancy. This book identifies the principles of transport in porous media and compares the avalaible predictions based on theoretical treatments of various transport mechanisms with the existing experimental results. The theoretical treatment is based on the volume-averaging of the momentum and energy equations with the closure conditions necessary for obtaining solutions. While emphasizing a basic understanding of heat transfer in porous media, this book does not ignore the need for predictive tools; whenever a rigorous theoretical treatment of a phenomena is not avaliable, semi-empirical and empirical treatments are given.