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Preface to the First Edition
Preface to the First Edition Multiphase flows exist in many natural and technological systems. Owing to the many challenges that are being faced by many applied scientists, practising engineers, undergraduate and graduate students or researchers engaging in the subject of multiphase flows, the advancement of digital computers has apparently refocussed the reliance on computational predictions to better understand and predict the multiphase phenomenon. With increasing prevalence, the feasibility of application of computational models is certainly gaining significant traction. Modelling multiphase flows, in general, encompasses a wide spectrum of different length scales, a broad range of engineering disciplines, and a multitude of different computational approaches. In spite of the comprehensive treatment in the subject of multiphase flows, a single text that provides a systematic exposition of a physical model utilising the computational fluid dynamics concepts, techniques and models remains elusive. Therefore, the authors truly understand the difficulties faced by multiphase modellers to gain sufficient knowledge in employing the necessary computational techniques and models in their investigative studies. For the uninitiated multiphase modeller who is learning about the basic concepts of computational fluid dynamics for the first time, the nitty-gritty elements within this particular mathematically sophisticated discipline can be rather difficult to master. For practical multiphase flows, appropriate models in aptly handling the complexity associated with the state of the different phases are, in general, required. Each of these models requires some prior basic knowledge of which the multiphase modeller may not have sufficiently acquired during his/her course of study. Therefore, the authors fully acknowledge the predicament of multiphase modellers in attempting to obtain sensible results for a range of fl ow problems by simply concentrating on the application rather than understanding the basic theory behind the formulation and limits of applicability of these models. Because of the increasing importance on the use of computational modelling of multiphase flows, the aim of the present text is to try to present the basic techniques used in the treatment of multiphase flows. The authors have tried to strike a balance by covering relevant materials that may be regarded as “ old-fashioned” as well as “new-fashioned.” On the former, the older, tried-and-proven ideas form a wonderfully intuitive and meaningful learning experience for the uninitiated multiphase modeller. On the latter, some extensive development on the computational techniques pertaining specifically to handle different forms of multiphase flows has been presented to keep updatedon the latest computational approaches that are currently being employed in the subject of multiphase flows. Because of the complex nature of multiphase flows, the authors have adopted an unconventional style of presenting the sequence of materials in this book, which has proven to be rather effective in conveying the treatment of different classifications of multiphase flows. For each classification of multiphase flows, every effort has been made to discuss the materials in easy-to-understand chapters (Chapters 4e9). Each of these chapters have been purposefully
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PREFACE TO THE FIRST EDITION
written to cover the relevant transport equations, multiphase models and numerical methods or techniques that are required to solve the appropriate multiphase flow. One feature of these chapters is that the materials are targeted precisely for the treatment of particular multiphase flow under consideration. For a more comprehensive review on the background theory and development especially on the governing equations and numerical methods, the reader can refer to Chapter 2, the governing equations and boundary conditions, and Chapter 3, solution methods for multiphase flows, respectively, which incidentally form the foundation chapters of this book where the building blocks of Chapters 4e9 are built on top of it. More importantly, the authors have provided an extensive range of worked examples in elucidating the application of specific computational techniques to best handle the different classifications of multiphase flows. As such these materials will go a long way to even satisfy the initiated multiphase modeller through an intuitive, physically oriented approach to multiphase modelling. The future trends in handling turbulent multiphase flows are subsequently described in Chapter 10. There, the authors aim to present other sophisticated models to circumvent current approaches to multiphase modelling and point towards the possible realization in resolving more complex multiphase flows. Dr Yeoh would like to acknowledge the untiring support and boundless tolerance of his wife, Natalie, and his older daughters, Genevieve and Ellana, and the new arrival of his youngest daughter, Clarissa, for their enormous understanding and unflinching encouragement during the seemingly unending hours spent in preparing and writing. Professor Tu would like to express his deep gratitude to his wife, Xue, and his son, Tian, who have provided their support in the writing of this text. Special thanks are given to Geoff Smaldon, who first initiated the idea of this book, and to Jonathan Simpson, who took over the project and provided much encouragement in the writing of this book. The authors are especially grateful to Elsevier, the publisher, who have offered immense assistance both in academic elucidation and professional skills in the publication process. To those that the authors have failed to mention but have been involved in one way or another, the authors extend their deepest heartfelt appreciation. Guan Heng Yeoh Jiyuan Tu.
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PREFACE TO THE FIRST EDITION
written to cover the relevant transport equations, multiphase models and numerical methods or techniques that are required to solve the appropriate multiphase flow. One feature of these chapters is that the materials are targeted precisely for the treatment of particular multiphase flow under consideration. For a more comprehensive review on the background theory and development especially on the governing equations and numerical methods, the reader can refer to Chapter 2, the governing equations and boundary conditions, and Chapter 3, solution methods for multiphase flows, respectively, which incidentally form the foundation chapters of this book where the building blocks of Chapters 4e9 are built on top of it. More importantly, the authors have provided an extensive range of worked examples in elucidating the application of specific computational techniques to best handle the different classifications of multiphase flows. As such these materials will go a long way to even satisfy the initiated multiphase modeller through an intuitive, physically oriented approach to multiphase modelling. The future trends in handling turbulent multiphase flows are subsequently described in Chapter 10. There, the authors aim to present other sophisticated models to circumvent current approaches to multiphase modelling and point towards the possible realization in resolving more complex multiphase flows. Dr Yeoh would like to acknowledge the untiring support and boundless tolerance of his wife, Natalie, and his older daughters, Genevieve and Ellana, and the new arrival of his youngest daughter, Clarissa, for their enormous understanding and unflinching encouragement during the seemingly unending hours spent in preparing and writing. Professor Tu would like to express his deep gratitude to his wife, Xue, and his son, Tian, who have provided their support in the writing of this text. Special thanks are given to Geoff Smaldon, who first initiated the idea of this book, and to Jonathan Simpson, who took over the project and provided much encouragement in the writing of this book. The authors are especially grateful to Elsevier, the publisher, who have offered immense assistance both in academic elucidation and professional skills in the publication process. To those that the authors have failed to mention but have been involved in one way or another, the authors extend their deepest heartfelt appreciation. Guan Heng Yeoh Jiyuan Tu.