Kern’s

Process Heat TransferSecond Edition

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Kern’s

Process Heat Transfer Second Edition

Ann Marie FlynnToshihiro Akashige

Louis Theodore

This edition first published 2019 by John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, USA

and Scrivener Publishing LLC, 100 Cummings Center, Suite 541J, Beverly, MA 01915, USA

© 2019 Scrivener Publishing LLC . First edition © Geoffrey L. Kern.

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Library of Congress Cataloging-in-Publication Data

Names: Flynn, Ann Marie, author. | Kern, Donald Quentin, 1914- author. |

Akashige, Toshihiro, author. | Theodore, Louis, author.

Title: Kern’s process heat transfer / Ann Marie Flynn, Toshihiro Akashige,

Louis Theodore.

Description: Second edition. | Hoboken, New Jersey : John Wiley & Sons, Inc.

; Salem, Massachusetts : Scrivener Publishing, [2018] | Includes

bibliographical references and index. |

Identifiers: LCCN 2018041527 (print) | LCCN 2018044072 (ebook) | ISBN

9781119364177 (ePub) | ISBN 9781119364832 (Adobe PDF) | ISBN 9781119363644

(hardcover)

Subjects: LCSH: Heat--Transmission | Chemical processes. | Thermodynamics. |

Heating

Classification: LCC TP363 (ebook) | LCC TP363 .F59 2018 (print) | DDC

621.402/2--dc23

LC record available at https://lccn.loc.gov/2018041527

Cover images: Russell Richardson

Cover design by: Russell Richardson

Set in size of 11pt and Minion Pro by Exeter Premedia Services Private Ltd., Chennai, India

Printed in the USA

10 9 8 7 6 5 4 3 2 1

Donald Q. Kern1914–1971

Donald Quentin Kern was born in New York City in 1914. He studied at the Massachusetts Institute of Technology and received his Bachelor’s, Master’s and Ph.D. in Chemical Engineering from the Polytechnic Institute of Brooklyn (now New York University Tandon School of Engineering) in 1942. He was employed by Foster Wheeler from 1940 to 1947, and became Director of the Process Engineering Division at the Patterson Foundry & Machine Company in 1948.

In 1950, he published what is now considered the landmark text, Process Heat Transfer. As the first applied heat transfer book, engineers worldwide have come to know Process Heat Transfer as the definitive applied heat trans-fer reference. Eventually, the term “process heat transfer” became a recog-nized specialty within heat transfer, particularly for chemical engineers.

In 1953, Dr. Kern moved to Cleveland where he became the Director of Engineering for the Chemical and Process division at Colonial Iron Works Company. He formed his own firm in Cleveland in 1954, D.Q. Kern and Associates. The company specialized in thermal process technology and served clients in the chemical, petroleum, nuclear, and assorted equip-ment industries. Kern also consulted for the Atomic Energy Commission and the Department of the Interior, and taught graduate courses at the Polytechnic Institute of Brooklyn and Case Western Reserve University.

Donald Kern’s fame would have been secured by Process Heat Transfer alone, but he also co-authored Extended Surface Heat Transfer (1972), pub-lished 60 papers and articles in heat transfer design and economics, and

lectured widely to engineering groups. Kern was also active profession-ally as a member of AIChE and ASME. He was a founder and Chair of the Heat Transfer and Energy Conversion Division of AIChE and Chair of the National Heat Transfer Conference Coordinating Committee. The legacy and contribution of Donald Q. Kern was ensured in 1973 when the AIChE Heat Transfer and Energy Conversion Division (now Transport and Energy Processes Division) commemorated their most prestigious, annual award in his honor.

With thanks to A.E. Bergles and W.J. Warner.

vii

Acknowledgement

Kern’s Process Heat Transfer, Second Edition was nearly a decade in the making, and a dream for Dr. Ann Marie Flynn. Introduced to the origi-nal text as both an undergraduate and graduate student, she subsequently adopted the book during her term as a professor of chemical engineering at Manhattan College. Nearly 70 years after its original publication, Dr. Kern’s Process Heat Transfer was still an extraordinary teaching tool.

It was through her efforts — the search to contact the Kern family, securing the copyright to the first edition, convincing Scrivener Publishing of the need for the book, and assembling the team to accomplish the job — that made her dream become a reality.

Dr. Flynn was able to locate the first member of the Kern family – Dr. Kern’s nephew, the son of his sister, Helen. His nephew recounted stories with Dr. Flynn: the day he served as ring bearer at his uncle’s wedding to the former Natalie Weiss; how he watched as the nearly 900 pages of the original manuscript were typed on a manual typewriter in the middle of Kern’s living room in New York city.

Dr. Kern’s son was located in Chicago (Kern’s wife and daughter had since passed). Kern’s son shared that he was very young when his father died in 1971, so he knew very little about his father’s work. He also shared that as an adult, while he and his wife were hiking in Canada, they came across an engineering firm and decided to stop in. By chance, he men-tioned that his father had once written a book – maybe they had heard of it? Dr. Kern’s son was amazed to discover that the engineers described his father’s book as the “Bible.”

Dr. Kern – son, husband, father, and brother passed away on March 2, 1971 at his home in Shaker Heights, Ohio. Services were held on March 4, 1971 at Riverside Chapel in New York city. In the 21 years since its first printing, Process Heat Transfer had been translated into Russian, Japanese, and Spanish by the time Donald Quentin Kern was laid to rest. He was 56 years old.

On behalf of all students who have already, or will benefit from Dr. Kern’s extraordinary work, the authors will be forever grateful for the blessing and consent provided by the Kern family to go forward with this project.

ix

Con te n ts(Fir s t Ed ition )

PREFACE ..................................................................................... v i i

INDEX TO THE PRINCIPAL APPARATUS CALCULATIONS ............. xi

CHAPTER

1 Pr oce ss He at Tr an sfe r ....................................... 12 Con d u ction ........................................................... 63 Con v e c tion ............................................................ 254 Rad iation .............................................................. 625 Te m p e r atu r e ........................................................ 856 Cou n te r flow : Dou b le -p ip e Exch an ge r s .......... 1027 1-2 Par alle l-cou n te r flow : Sh e ll-an d -Tu b e

xch an ge r s .......................................................... 1278 Flow Ar r an ge m e n ts for In cr e ase d He at

Re cov e r y ............................................................... 1759 Gase s ...................................................................... 190

10 Str e am lin e Flow an d Fr e e Con v e c tion .......... 20111 Calcu lation s for Pr oce ss Con d ition s .............. 22112 Con d e n sation of Sin gle Vap or s ....................... 25213 Con d e n sation of Mixe d Vap or s ....................... 31314 Ev ap or ation ......................................................... 37515 Vap or ize r s , Ev ap or ator s , an d Re b oi le r s ....... 45316 Exte n d e d Su r face s .............................................. 51217 Dir e c t-con tac t Tr an sfe r : Coolin g Tow e r s ..... 56318 Batch an d Un ste ad y State Pr oce sse s ............. 62419 Fu r n ace Calcu lation s ......................................... 67420 Ad d ition al Ap p lication s .................................... 71621 Th e Con tr o l of Te m p e r atu r e an d Re late d

Pr oce ss Var iab le s ................................................ 765

e

x Contents (First Edition)

APPENDIX OF CALCULATION DATA ........................................... 791

AUTHOR INDEX ........................................................................ 847

SUBJECT INDEX ....................................................................... 851

xi

Pr e face (F ir s t Ed ition )

It is the object of this text to provide fundamental instruction in heat transfer while employing the methods and language of industry. This treatment of the subject has evolved from a course given at the Polytechnic Institute of Brooklyn over a period of years. The possibilities of collegiate instruction pat-terned after the requirements of the practicing process engineer were suggested and encouraged by Dr. Donald F. Othmer, Head of the Department of Chemical Engineering. The inclusion of the practical aspects of the subject as an integral part of the pedagogy was intended to serve as a supplement rather than a substitute for a strong foundation in engineering fundamentals. These points of view have been retained throughout the writing of the book.

To provide the rounded group of heat-transfer tools required in process engineering it has been necessary to present a num-ber of empirical calculation methods which have not previously appeared in the engineering literature. Considerable thought has been given to these methods, and the author has discussed them with numerous engineers before accepting and including them in the text. It has been a further desire that all the calcu-lations appearing in the text shall have been performed by an experienced engineer in a conventional manner. On several occa-sions the author has enlisted the aid of experienced colleagues, and their assistance is acknowledged in the text. In presenting several of the methods some degree of accuracy has been sacri-ficed to permit the broader application of fewer methods, and it is hoped that these simplifications will cause neither inconve-nience nor criticism.

It became apparent in the early stages of writing this book that it could readily become too large for convenient use, and this has affected the plan of the book in several important respects.

xii Preface (First Edition)

A portion of the material which is included in conventional texts is rarely applied in the solution of run-of-the-mill engineering problems. Such material, as familiar and accepted as it may be, has been omitted unless it qualified as important fundamental information. Secondly, it was not possible to allocate space for making bibliographic comparisons and evaluations and at the same time present industrial practice. Where no mention has been made of a recent contribution to the literature no slight was intended. Most of the literature references cited cover methods on which the author has obtained additional information from industrial application.

The author has been influenced in his own professional development by the excellent books of Prof. W. H. McAdams, Dr. Alfred Schack, and others, and it is felt that their influence should be acknowledged separately in addition to their incidence in the text as bibliography.

For assistance with manuscript indebtedness is expressed to Thomas H. Miley, John Blizard, and John A. Jost, former associates at the Foster Wheeler Corporation. For checking the numerical calculations credit is due to Krishnabhai Desai and Narendra R. Bhow, graduate students at the Polytechnic Institute. For suggestions which led to the inclusion or exclu-sion of certain material thanks are due Norman E. Anderson, Charles Bliss, Dr. John F. Middleton, Edward L. Pfeiffer, Oliver N. Prescott, Everett N. Sieder, Dr. George E. Tait, and to Joseph Meisler for assistance with proof. The Tubular Exchanger Manufacturers Association has been most generous in granting permission for the reproduction of a number of the graphs con-tained in its Standard. Thanks are also extended to Richard L. Cawood, President, and Arthur E. Kempler, Vice-President, for their personal assistance and for the cooperation of the Patterson Foundry & Machine Company.

Don ald Q. Ke r nNew York City, N.Y.

April 1950

To:

Donald Q. Kern,

Without whom, all of this would not have been possible.

Ann Marie Flynn

To:

My beloved parents, Hidenori and Mieko Akashige,My dearest friends, MD Azim, Corine Laplanche,

Christopher Cacciavillani, Kleant Daci, Michael Pryor, and Anet Kashoa,

My brother, TetsuyaMy peers from the classes of 2017 and 2018 of Manhattan College,

Coauthor and colleague, Dr. Louis Theodore,and

My extraordinary mentor, Dr. Ann Marie Flynn.

Toshihiro AkashigeTo:

Ann Marie Flynn,

A very special person, dedicated to education, who has somehow managed to survive Manhattan College,

and for inviting me to contribute to this unique undertaking.

Louis Theodore

xiii

xv

Contents to the Second Edition

Acknowledgement vii

Contents (First Edition) ix

Preface (First Edition) xi

Dedication xiii

Contents to the Second Edition xv

Preface to the Second Edition xxi

Part I Fundamentals and Principles 1

1 Introduction to Process Heat Transfer 3Introduction 31.1 Units and Dimensional Analysis 41.2 Key Physical Properties 101.3 Key Process Variables and Concepts 141.4 Laws of Thermodynamics 221.5 Heat-Related Theories and Transfer Mechanisms 261.6 Fluid Flow and Pressure Drop Considerations 281.7 Environmental Considerations 351.8 Process Heat Transfer 39References 40

2 Steady-State and Unsteady-State Heat Conduction 43Introduction 432.1 Flow of Heat through a Plane Wall 462.2 Flow of Heat through a Composite Plane Wall:

Resistances in Series 502.3 Flow of Heat through a Pipe Wall 54

xvi Contents to the Second Edition

2.4 Flow of Heat through a Composite Pipe Wall: Resistances in Series 57

2.5 Steady-State Conduction: Microscopic Approach 632.6 Unsteady-State Heat Conduction 682.7 Unsteady-State Conduction: Microscopic Approach 71References 77

3 Forced and Free Convection 79Introduction 793.1 Forced Convection Principles 823.2 Convective Resistances 873.3 Heat Transfer Coefficients: Quantitative Information 893.4 Convection Heat Transfer: Microscopic Approach 1053.5 Free Convection Principles and Applications 1083.6 Environmental Applications 120References 127

4 Radiation 129Introduction 1294.1 The Origin of Radiant Energy 1324.2 The Distribution of Radiant Energy 1334.3 Radiant Exchange Principles 1384.4 Kirchoff ’s Law 1394.5 Emissivity Factors and Energy Interchange 1454.6 View Factors 153References 157

Part II Heat Exchangers 159

5 The Heat Transfer Equation 161Introduction 1615.1 Heat Exchanger Equipment Classification 1625.2 Energy Relationships 1635.3 Log Mean Temperature Difference (LMTD)

Driving Force 1665.4 The Overall Heat Transfer Coefficient (U) 1835.5 The Heat Transfer Equation 208References 216

6 Double Pipe Heat Exchangers 217Introduction 2176.1 Equipment Description and Details 218

Contents to the Second Edition xvii

6.2 Key Describing Equations 2256.3 Calculation of Exit Temperatures 2446.4 Pressure Drop in Pipes and Pipe Annuli 2516.5 Open-Ended Problems 2546.6 Kern’s Design Methodology 2626.7 Practice Problems from Kern’s First Edition 285References 286

7 Shell-and-Tube Heat Exchangers 289Introduction 2897.1 Equipment Description and Details 2907.2 Key Describing Equations 3077.3 Open-Ended Problems 3337.4 Kern’s Design Methodology 3397.5 Other Design Procedures and Applications 3507.6 Computer Aided Heat Exchanger Design 3727.7 Practice Problems from Kern’s First Edition 376References 379

8 Extended Surface/Finned Heat Exchangers 381Introduction 3818.1 Fin Details 3828.2 Equipment Description 3888.3 Key Describing Equations 3908.4 Fin Effectiveness and Performance 3988.5 Kern’s Design Methodology 4188.6 Other Fin Considerations 4338.7 Practice Problems from Kern’s First Edition 434References 435

9 Other Heat Exchangers 437Introduction 4379.1 Condensers 4399.2 Evaporators 4509.3 Boilers and Furnaces 4709.4 Waste Heat Boilers 4809.5 Cogeneration/Combined Heat and Power (CHP) 4889.6 Quenchers 4929.7 Cooling Towers 4989.8 Heat Pipes 508References 510

xviii Contents to the Second Edition

Part III Peripheral Topics 513

10 Other Heat Transfer Considerations 515Introduction 51510.1 Insulation and Refractory 51610.2 Refrigeration and Cryogenics 53310.3 Instrumentation and Controls 54610.4 Batch and Unsteady-State Processes 55510.5 Operation, Maintenance, and Inspection (OM&I) 56110.6 Economics and Finance 569References 585

11 Entropy Considerations and Analysis 589Introduction 58911.1 Qualitative Review of the Second Law 59011.2 Describing Equations 59111.3 The Heat Exchanger Dilemma 59511.4 Application to a Heat Exchanger Network 603References 606

12 Health and Safety Concerns 607Introduction 60712.1 Definitions 61112.2 Legislation 62012.3 Material Safety Data Sheets 62312.4 Health Risk versus Hazard Risk 62812.5 Health Risk Assessment 62912.6 Hazard Risk Assessment 640References 650

Appendix 653

TablesAT.1 Conversion Constants 654AT.2 Thermodynamic Properties of Steam/Steam Tables 658AT.3 Properties of Water (Saturated Liquid) 667AT.4 Properties of Air at 1 atm 669AT.5 Properties of Selected Liquids at 1 atm and 20 C (68 F) 670AT.6 Properties of Selected Gases at 1 atm and 20 C (68 F) 670AT.7 Dimensions, Capacities, and Weights of Standard

Steel Pipes 674AT.8 Dimensions of Heat Exchanger Tubes 676

Contents to the Second Edition xix

AT.9 Tube-Sheet Layouts (Tube Counts) on a Square Pitch 678AT.10 Tube-Sheet Layouts (Tube Counts) on

a Triangular Pitch 680AT.11 Approximate Design Overall Heat Transfer

Coefficients (Btu/hr∙ft2∙ F) 683AT.12 Approximate Design Fouling Coefficient

Factors (hr∙ft2∙ F/Btu) 684

FiguresAF.1 Fanning Friction Factor (f) vs. Reynolds Number (Re) Plot 688AF.2 Psychometric Chart: Low Temperatures:

Barometric Pressure, 29.92 in. Hg. 689AF.3 Psychometric Chart: High Temperatures:

Barometric Pressure, 29.92 in. Hg. 690

Index 691

xxi

Preface to the Second Edition

A second edition? After 65 plus years? Is it reasonable? Does it make sense from a technical and publication perspective? The answer is ordinarily “No.” But for Donald Q. Kern’s classic heat transfer book, Process Heat Transfer, the answer is definitely “Yes.”

The first edition sold approximately 65,000 copies over its lifetime. And for good reason. It stands alongside the powerhouse classics in the chemi-cal engineering literature: Treybal’s Mass Transfer Operations, McCabe and Smith’s Unit Operations of Chemical Engineering, Bird, Stewart, and Lightfoot’s Transport Phenomena (with the second edition arriving on the scene after a half century), etc.

As Kern put it in his Preface: “the object of this text is to promote instruction in heat transfer while employing the methods and language of industry by providing the heat transfer tools required in process engi-neering.” Unbelievably, this book still achieves many of its original objec-tives as many practicing (chemical) engineers involved with heat transfer design include this book as part of their library – as evidenced by an email from a former Manhattan College student who is now working as a Process Engineer:

Subject Line: Can’t Escape KernDate: 5/27/14

I had some calcs to do;Director handed me these off his desk.

Regards,

Will Gallei

xxii Preface to the Second Edition

Even though the relentless passage of time has brought about many changes to the past, there have been relatively few truly innovative changes to the heat transfer equipment employed by industry since 1950 – and that may or may not be good. Still, there are changes that need to be addressed if Kern’s original work is to continue to remain relevant in the 21st century process engineering literature. Topics that are part of the current engineers’ vocabulary but need to be addressed include (but are not limited to) energy conservation and the associated topic of quality energy, nanomaterials, environmental considerations, health and safety (and the accompanying topic of risk), packaged calculation programs, the move from engineering units to the International System of Units (SI), etc.

Some of the above factors convinced the authors of the need for an update to Kern’s classic work so that students would find an easy transition from classroom examples to industrial applications. From an educational perspective, the lead author of this second edition (Flynn) has employed Kern’s Process Heat Transfer as the primary text in the junior-year chemi-cal engineering course at Manhattan College for 18 years. One of the co-authors (Theodore) attempted to model his recent 2013 heat transfer book, Heat Transfer Applications for the Practicing Engineering (John Wiley & Sons) after Kern’s book.

Kern’s second edition is divided into three Parts: Fundamentals and Principles, Heat Exchangers, and Peripheral Topics. The first Part provides a series of chapters concerned with introductory topics that are required when solving heat transfer problems. This part of the book deals with heat transfer principles; topics that receive treatment include steady-state heat conduc-tion, unsteady-state heat conduction, forced convection, free convection, and radiation. Part II is considered by the authors to be the “meat” of the book – addressing heat transfer equipment design procedures and applica-tions. In addition to providing a more meaningful treatment of the various types of heat exchangers, this Part also examines the roles of computers on predicting the performance and the design of heat transfer equipment. It also should be noted that Kern’s original practice problems were included in this part. The concluding Part of the book examines other related topics of interest including insulation and refractory, refrigeration and cryogenics, boilers, cooling towers, quenchers, heat pipes, and batch and unsteady-state processes health and hazard risk, and entropy considerations.

A comment on units and notations. The original units and nota-tions employed by Kern were essentially retained. A short write-up on the International System of Units (SI) is provided in the Appendix to accommodate the clamor for metric units; unit conversion tables are also

Preface to the Second Edition xxiii

included. This accommodation was included despite industry’s continual use of British Engineering units. Finally, and for obvious reasons, Kern adopted chemical engineering notation; fortunately, they have – for the most part – been retained by industry.

The changes to the present edition have evolved from a host of sources, including: course notes, homework assignments, and exam problems pre-pared by Ann Marie Flynn for a core, three-credit, undergraduate course, “Chemical Engineering Principles II: Heat Transfer,” offered by Manhattan College; I. Farag and J. Reynolds, Heat Transfer, A Theodore Tutorial, East Williston, N.Y., 1994; and J. Reynolds, J. Jeris, and L. Theodore, Handbook of Chemical and Environmental Engineering Calculations, John Wiley & Sons, Hoboken, NJ, 2004. Although the bulk of the new material is original and/or taken from sources that the authors have been directly involved with, every effort has been made to acknowledge material drawn from other sources.

Our sincere thanks are extended to Kleant Daci, Michael Pryor, and Anet Kashoa as contributing authors for Chapter 9, Chapter 10, and Chapter 11, respectively. We also appreciate the extraordinary insight and guidance provided by Francesco Ricci and Paul Farber during the writing of this book.

Ann Marie FlynnToshihiro Akashige

Louis TheodoreFloral Park, N.Y.

March, 2019

Note: The authors are in the process of developing a useful resource in the form of a website which will contain over 150 additional problems and 15 hours of exams; solutions for these problems and exams will be available for those who adopt the book for training and/or academic purposes.

Part I

FUNDAMENTALS AND

PRINCIPLES

3

1Introduction to Process Heat Transfer

Introduction

The science of thermodynamics deals with the quantitative transitions and rearrangements of energy as heat in bodies of matter. Heat transfer is the science which deals with the rates of exchange of heat between hot and cold bodies called the source and receiver, respectively. The equipment employed to bring about this heat exchange is referred to as a heat exchanger.

Perhaps the simplest example of the various types of heat exchangers is the double pipe heat exchanger, a unit that will receive extensive treat-ment in Part II, Chapter 6. A simple diagram representing this exchanger is provided in Figure 1.1. This unit consists of two concentric pipes. Each of the two fluids — hot and cold — flow either through the inside of the inner pipe or through the annulus formed between the outside of the inner pipe and the inside of the outer pipe. Generally, it is more economi-cal (from heat efficiency and design perspectives) for the hot fluid (the source) to flow-through the inner pipe and the cold fluid (the receiver)

4 Kern’s Process Heat Transfer, 2nd Edition

through the annulus, thereby reducing heat losses from the hot fluid to the surroundings.

Fundamentally, a temperature difference between the two bodies in close proximity (or between two parts of the same body) results in heat flow from higher to lower temperatures. There are three different (and classic) mechanisms by which this heat transfer can occur: conduction, convection, and radiation. When the heat transfer is the result of molecular motion (e.g., the vibrational energy of molecules in a solid being passed along from molecule to molecule), the mechanism of transfer is conduction. When heat transfer results from macroscopic motion, such as currents in a fluid, the mechanism is convection. When heat is transferred by electromagnetic waves, radiation is the mechanism. In most industrial applications, multi-ple mechanisms are usually involved in the transmission of heat. However, since each mechanism is governed by its own set of physical laws, it is ben-eficial to discuss them independently of each other (see Chapters 2–4).

This introductory chapter consists of the following eight sections:

1.1 Units and Dimensional Analysis 1.2 Key Physical Properties 1.3 Key Process Variables and Concepts 1.4 Laws of Thermodynamics 1.5 Heat-related Theories and Transfer Mechanisms 1.6 Fluid Flow and Pressure Drop Considerations 1.7 Environmental Considerations 1.8 Process Heat Transfer

1.1 Units and Dimensional Analysis

This section is primarily concerned with units. The units used in the text are consistent with those adopted by the engineering profession in the United States [1–3]. One usually refers to them as English or engineering

Figure 1.1 Line diagram of a cocurrent flow heat exchanger.

Cold fluid in

Heat exchangerHot fluid in Hot fluid out

Cold fluid out