Conjugate Problems in Convective Heat Transfer 8237X_C000.indd 1 7/24/09 6:33:43 PM H T EAT RANSFER A Series of Reference Books and Textbooks Editor Afshin J. Ghajar Regents Professor School of Mechanical and Aerospace Engineering Oklahoma State University 1. Engineering Heat Transfer: Third Edition, William S. Janna 2. Conjugate Problems in Convective Heat Transfer, Abram S. Dorfman Upcoming titles include: Introduction to Thermal and Fluid Engineering, Allan D. Kraus, James R. Welty, and Abdul Aziz 8237X_C000.indd 2 7/28/09 10:33:37 AM Conjugate Problems in Convective Heat Transfer Abram S. Dorfman Boca Raton London New York CRC Press is an imprint of the Taylor & Francis Group, an informa business 8237X_C000.indd 3 7/24/09 6:33:43 PM CRC Press Taylor & Francis Group 6000 Broken Sound Parkway NW, Suite 300 Boca Raton, FL 33487-2742 © 2010 by Taylor and Francis Group, LLC CRC Press is an imprint of Taylor & Francis Group, an Informa business No claim to original U.S. Government works Printed in the United States of America on acid-free paper 10 9 8 7 6 5 4 3 2 1 International Standard Book Number: 978-1-4200-8237-1 (Hardback) This book contains information obtained from authentic and highly regarded sources. Reasonable efforts have been made to publish reliable data and information, but the author and publisher cannot assume responsibility for the validity of all materials or the consequences of their use. The authors and publishers have attempted to trace the copyright holders of all material reproduced in this publication and apologize to copyright holders if permission to publish in this form has not been obtained. If any copyright material has not been acknowledged please write and let us know so we may rectify in any future reprint. Except as permitted under U.S. Copyright Law, no part of this book may be reprinted, reproduced, transmit- ted, or utilized in any form by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying, microfilming, and recording, or in any information storage or retrieval system, without written permission from the publishers. For permission to photocopy or use material electronically from this work, please access www.copyright. com (http://www.copyright.com/) or contact the Copyright Clearance Center, Inc. (CCC), 222 Rosewood Drive, Danvers, MA 01923, 978-750-8400. CCC is a not-for-profit organization that provides licenses and registration for a variety of users. For organizations that have been granted a photocopy license by the CCC, a separate system of payment has been arranged. Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe. Library of Congress Cataloging-in-Publication Data Dorfman, A. Sh. (Abram Shlemovich) Conjugate problems in convective heat transfer / Abram S. Dorfman. p. cm. -- (Heat transfer) Includes bibliographical references and index. ISBN 978-1-4200-8237-1 (hardcover : alk. paper) 1. Heat--Transmission. 2. Heat--Convection. 3. Fluid dynamics. I. Title. TJ260.D64 2009 621.402’25--dc22 2009018850 Visit the Taylor & Francis Web site at http://www.taylorandfrancis.com and the CRC Press Web site at http://www.crcpress.com 8237X_C000.indd 4 7/24/09 6:33:43 PM In Memory In memory of our dearest, lovely, loving daughter, Ella Fridman. 8237X_C000.indd 5 7/24/09 6:33:43 PM 8237X_C000.indd 6 7/24/09 6:33:43 PM Contents List of Examples ....................................................................................................xi Preface .................................................................................................................xvii Acknowledgments .............................................................................................xxi The Author ........................................................................................................xxiii Introduction .......................................................................................................xxv Nomenclature ..................................................................................................xxvii Part I: Approximate Solutions Chapter 1 Analytical Methods for the Estimation of Heat Transfer from Nonisothermal Walls ............................................................................................3 1.1 Basic Equations...............................................................................................3 1.2 Self-Similar Solutions of the Boundary Layer Equations ........................4 1.3 Solutions of the Boundary Layer Equations in the Power Series ...........5 1.4 Integral Methods ............................................................................................7 1.5 Method of Superposition ............................................................................12 1.6 Solutions of the Boundary Layer Equations in the Series of Shape Parameters ....................................................................................16 References ...............................................................................................................18 Chapter 2 Approximate Solutions of Conjugate Problems in Convective Heat Transfer ........................................................................................................21 2.1 Formulation of a Conjugate Problem of Convective Heat Transfer ................................................................................................21 2.2 The Case of Linear Velocity Distribution across the Thermal Boundary Layer ............................................................................................22 2.3 The Case of Uniform Velocity Distribution across the Thermal Boundary Layer (Slug Flow) .......................................................................28 2.4 Solutions of the Conjugate Convective Heat Transfer Problems in the Power Series .......................................................................................35 2.5 Solutions of the Conjugate Heat Transfer Problems by Integral Methods .........................................................................................................46 References ...............................................................................................................50 vii 8237X_C000.indd 7 7/24/09 6:33:43 PM viii Contents Part II: Theory and Methods Chapter 3 Heat Transfer from Arbitrary Nonisothermal Surfaces in a Laminar Flow ...............................................................................55 3.1 The Exact Solution of the Thermal Boundary Layer Equation for an Arbitrary Surface Temperature Distribution ...............................55 3.2 Generalization for an Arbitrary Velocity Gradient in a Free Stream Flow ..................................................................................62 3.3 General Form of the Influence Function of the Unheated Zone: Convergence of the Series..............................................64 3.4 The Exact Solution of the Thermal Boundary Layer Equation for an Arbitrary Surface Heat Flux Distribution ....................69 3.5 Temperature Distribution on an Adiabatic Surface in an Impingent Flow ............................................................................................73 3.6 The Exact Solution of an Unsteady Thermal Boundary Layer Equation for Arbitrary Surface Temperature Distribution ....................75 3.7 The Exact Solution of a Thermal Boundary Layer Equation for a Surface with Arbitrary Temperature in a Compressible Flow ...........78 3.8 The Exact Solution of a Thermal Boundary Layer Equation for a Moving Continuous Surface with Arbitrary Temperature Distribution ...........................................................................79 3.9 The Other Solution of a Thermal Boundary Layer Equation for an Arbitrary Surface Temperature Distribution ...............................83 3.9.1 Non-Newtonian Fluid with a Power Law Rheology ..................83 3.9.2 The Effect of Mechanical Energy Dissipation .............................86 3.9.3 Axisymmetric Streamlined and Rotating Bodies .......................87 3.9.4 Thin Cylindrical Bodies ..................................................................89 References ...............................................................................................................91 Chapter 4 Heat Transfer from Arbitrary Nonisothermal Surfaces in Turbulent Flow ................................................................................................95 4.1 Basis Relations for the Equilibrium Boundary Layer .............................95 4.2 Solution of the Thermal Turbulent Boundary Layer Equation for an Arbitrary Surface Temperature Distribution ...............................99 4.3 Intensity of Heat Transfer from an Isothermal Surface: Comparison with Experimental Data .....................................................104 4.3.1 Reynolds Analogy .........................................................................104 4.3.2 Relations for Heat Transfer from an Isothermal Surface in Gradientless Flow ........................................................105 4.3.3 Relations for Heat Transfer from an Isothermal Surface in Gradient Flows.............................................................109 4.4 The Effect of the Turbulent Prandtl Number on Heat Transfer on Flat Plates ...............................................................................................111 8237X_C000.indd 8 7/24/09 6:33:43 PM Contents ix 4.5 Coefficients g of Heat Flux Series for Nonisothermal Surfaces .........112 k 4.6 Approximate Relations for Heat Flux in a Transition Regime ............116 References .............................................................................................................118 Chapter 5 General Properties of Nonisothermal and Conjugate Heat Transfer ........121 5.1 The Effect of Temperature Head Distribution on Heat Transfer Intensity .......................................................................................................121 5.1.1 The Effect of the Temperature Head Gradient ..........................122 5.1.2 The Effect of Flow Regime ............................................................132 5.1.3 The Effect of Pressure Gradient ...................................................137 5.2 Gradient Analogy and Reynolds Analogy ............................................137 5.3 Heat Flux Inversion ...................................................................................141 5.4 Zero Heat Transfer Surfaces .....................................................................148 5.5 Examples of Optimizing Heat Transfer in Flow over Bodies..............150 References .............................................................................................................158 Chapter 6 Analytical Methods for Solving Conjugate Convective Heat Transfer Problems ..............................................................................................161 6.1 A Biot Number as a Criterion of the Conjugate Heat Transfer Rate ...............................................................................................161 6.2 General Boundary Condition for Convective Heat Transfer Problems: Errors Caused by Boundary Condition of the Third Kind ....162 6.3 Reduction of a Conjugate Convective Heat Transfer Problem to an Equivalent Heat Conduction Problem ..........................................166 6.4 Temperature Singularities on the Solid–Fluid Interface ......................179 6.4.1 Basic Equations...............................................................................179 6.4.2 Examples of Singularities for Different Flow Regimes and Conditions ...............................................................................181 6.4.3 Estimation of Accuracy of the Assumption of a Thermally Thin Body ....................................................................183 6.5 Universal Functions for Solving Conjugate Heat Transfer Problems — Solution Examples ...............................................................183 6.6 Reducing the Unsteady Conjugate Convective Heat Transfer Problem to an Equivalent Heat Conduction Problem ..........................198 6.6.1 Validity of Quasi-Steady Approximation — The Luikov Number as a Conjugate Criterion in Unsteady Heat Transfer .....199 6.6.2 Universal Eigenfunctions for Unsteady Conjugate Heat Transfer Problems ..........................................................................201 6.7 Integral Transforms and Similar Methods ............................................206 6.8 Solutions in Asymptotic Series in Eigenfunctions ...............................210 6.9 Superposition and Other Methods ..........................................................220 6.10 Green’s Function and the Method of Perturbation ...............................224 References .............................................................................................................227 8237X_C000.indd 9 7/24/09 6:33:43 PM
Description: