Table Of ContentCooling of Electronic Systems
NATO ASI Series
Advanced Science Institutes Series
A Series presenting the results of activities sponsored by the NATO Science Committee,
which aims at the dissemination of advanced scientific and technological knowledge,
with a view to strengthening links between scientific communities.
The Series is published by an international board of publishers in conjunction with the
NATO Scientific Affairs Division
A Life Sciences Plenum Publishing Corporation
B Physics London and New York
C Mathematical Kluwer Academic Publishers
and Physical Sciences Dordrecht, Boston and London
D Behavioural and Social Sciences
E Applied Sciences
F Computer and Systems Sciences Springer-Verlag
G Ecological Sciences Berlin, Heidelberg, New York, London,
H Cell Biology Paris and Tokyo
I Global Environmental Change
NATO-PCO-DATA BASE
The electronic index to the NATO ASI Series provides full bibliographical references
(with keywords and/or abstracts) to more than 30000 contributions from international
scientists published in all sections of the NATO ASI Series.
Access to the NATO-PCO-DAT A BASE is possible in two ways:
- via online FILE 128 (NATO-PCO-DATA BASE) hosted by ESRIN,
Via Galileo Galilei, 1-00044 Frascati, Italy.
- via CD-ROM "NATO-PCO-DATA BASE" with user-friendly retrieval software in
English, French and German (©WTV GmbH and DATAWARE Technologies Inc.
1989).
The CD-ROM can be ordered through any member of the Board of Publishers or
through NATO-PCO, Overijse, Belgium.
Series E: Applied Sciences-Vol. 258
Cooling of Electronic Systems
edited by
S.
Kaka~
University of Miami,
Coral Gables, Florida, U.S.A.
H. YOncO
Middle East Technical Ul')iversity,
Ankara, Turkey
and
K. Hijikata
Tokyo Institute of Technology,
Tokyo, Japan
Springer-Science+Business Media, B.V.
Proceedings of the NATO Advanced Study Institute on
Cooling of Electronic Systems
Cesme /lzmir, Turkey
June 21-July 2, 1993
A C.I.P. Catalogue record for this book is available from the Ubrary of Congress.
ISBN 978-94-010-4476-9 ISBN 978-94-011-1090-7 (eBook)
DOI 10.1007/978-94-011-1090-7
Printed on acid-free paper
All Rights Reserved
© 1994 Springer Science+B usiness Media Dordrecht
Originally published by Kluwer Academic Publishers in 1994
Softcover reprint of the hardcover 1st edition 1994
No part of the material protected by this copyright notice may be reproduced or
utilized in any form or by any means, electronic or mechanical, including photo
copying, recording or by any information-storage and retrieval system, without written
permission from the copyright owner.
TABLE OF CONTENTS
Preface ix
S. Kaka,
Introduction to ASI on Cooling of Electronic Systems 1
A. Bar-Cohen
Trends in the Packaging of Computer Systems 17
S. Oktay
Beyond Thermal Limits in Computer Systems Cooling 47
R.C. Chu and R.E. Simons
Cooling Technology for High Performance Computers: Design Applications 71
R.C. Chu and R.E. Simons
Cooling Technology for High Performance Computers: ffiM Sponsored Uriiversity
Re~~h 97
T. O'Meara and D. Poulikakos
Natural Convection Cooling of an Array of Heated Plates Simulating Printed
Circuit Boards 123
RA. Wirtz, W. Chen and D. Colban
Convection in Arrays of Electronic Packages Containing Longitudinal Fin Heat
Sinks 145
F. Mayinger and Z.G. Wang
Experiments on Natural Convective Air Cooling of a PCBs Array in a Closed
Casing with Inclination 165
M. Unsal
Cooling of Multiple Heat Sources Attached to Two Dimensional Rectangular Fins 179
M. Mobedi, H. Yuncu and B. Yucel
Natural Convection Heat Transfer from Horizontal Rectangular Fin Arrays 189
D. Poulikakos and A. Wietrzak
Cooling of a Microelectronic Sensor by Turbulent Forced Convection 203
vi
M.S. Soylemez and M. ilnsal
Computation of Steady Laminar Natural Convective Heat Transfer from
Localized Heat 225
S. Kaka' and R.M. Cotta
Unsteady Forced Convection in a Duct with and without Array of Block-Like
Electronic Components 239
A. Bejan and S.W. Lee
Optimal Geometry of Convection Cooled Electronic Packages 277
M. lshizuka
A Thermal Design Approach for Electronic Equipment by use of a Personal
Computer and Flow Visualization 293
C. Herman
Experimental Visualization of Temperature Fields and Measurement of Heat Transfer
Enhancement in Electronic System Models 313
M. Can and E. Pulat
Cooling of Electronic Systems by Impinging Air Jets 339
K. Hijikata, K. Fushinobu, T. Nagasaki and P.E. Phelan
Numerical and Experimental Studies for the Conjugate Direct Cooling of a Micro
Heat Generating Element 361
RJ. Krane, I. Ahmed and R. Parsons
The Cooling of Electronic Components with Flat Plate Heat Sinks 391
A. Bar-Cohen
Fundamentals of Nucleate Pool Boiling of Highly-Wetting Dielectric Liquids 415
F.P. lncropera and S. Ramadhyani
Single-Phase Liquid Jet Impingement Cooling of High-Performance Chips 457
F.P. Incropera and S. Ramadhyani
Application of Channel Flows to Single-Phase Liquid Cooling of Chips and
Multi-Chip Modules 507
A.E. Bergles and A. Bar-Cohen
Immersion Cooling of Digital Computers 539
M. Mermet-Guyennet and P. Lecocq
Boiling Coupled with Air Cooling 623
vii
RJ. Krane, J.C. Andersen, J.R. Parsons and A. Bar-Cohen
Thermal Control for Cryogenically Cooled Computer Systems 643
H. Yanca and S. Kaka~
Thermal Contact Conductance-Theory and Applications 677
AD. Kraus
Analysis of Extended Surface Arrays for Air-Cooled Electronic Equipment 703
AD. Kraus
The Choking of Finned Arrays 735
RM. Cotta and R. Ramos
Error Analysis and Improved Formulations for Extended Surfaces 753
A. Bar-Cohen and W .B. Krueger
Detennination of the Weighted-Average Case Temperature for a Single Chip
Package 789
AK. Stubos, N. Kanellopoulos and A. Mitropoulos
Network Modelling of Two-Phase Flow in Porous Structures: An Alternative for
the Study of Chip Cooling Enhancement 811
C J.M. Lasance
Accurate Temperature Prediction in Consumer Electronics: A Must but still a
Myth 825
C J.M. Lasance
Pragmatic Methods for Determining the Parameters Required for the Thermal
Analysis of Electronic Systems 859
AN. Salamatin, VA. Chugunov and O.V. Yartsev
Effective Heat Transfer Coefficients and Temperature Modelling in Electronic
Systems 899
W.Nakayama
Information Processing and Heat Transfer Engineering: Some Generic Views on
Future Research Needs 911
RJ. Krane
Research Needs in Thermal Management of Electronic Systems 945
Index 959
Preface
This volume contains an archived record of the NATO Advanced Study Institute
on Cooling of Electronic Systems held in Cesme-Izmir, Turkey, June 21-July 2, 1993.
The NATO ASis are intended to be high level teaching activities in scientific and
technical areas of current concern. Certainly, the subject of cooling of electronics
needs no justification in this regard. The current trend in electronics is towards
packing more and more circuits in a given space. Therefore circuit power has been
increased to increase circuit speed, and the circuits should operate within specified
temperature limits. The trend towards higher packaging densities and ever higher
heat fluxJlt the module level places importance on the development of heat removal
problems of electronic systems. The modes of heat transfer are often tied together,
which makes the heat transfer problems in electronic systems more challenging.
Because of this fact, heat transfer groups in both the electronics industry and at
universities are concerned with the thermal management of electronic the equipment.
Great improvements in the efficiency of the design and operation could be realized
if the fundamentals of cooling of electronics and micro-electronic devices were better
understood.
The invited lecturers reviewed the current state-of-knowledge of cooling of
electronic systems: The evolution of integrated circuit chips over the years and
leading cooling technologies are described. Natural convection, mixed and forced
convection and turbulent forced convection, unsteady forced convection for the
geometries arising in natural convection and forced convection cooling of electronics
are presented.
Because of the high heat transfer coefficients with liquid, liquid cooling will become
a preferable cooling technique for future electronic systems. Applications of single
phase liquid cooling, fundamentals of nucleate pool boiling of dielectricJiquid boiling
coupled with air cooling including enhancement are presented. Design parameters
of fm efficiency, fin effectiveness, fin admittance and the choking of finned arrays are
presented.
Data from literature regarding the hardware dimensions, power consumption at
the system levels and the rate of heat dissipation at the component level are
discussed and the advances in manufacturing and assembling technology are reviewed.
Practical methods fur the determination of the parameters required· for the thermal
analysis of electronic systems and accurate temperature predication in consumer
electronics are discussed.
ix
X
The sponsorship of the NATO Scientific Affairs Division are greatfully
acknowledged.
Our special gratitude goes to Drs. N. Egrican, T. Ayhan and M. Onsal for their
help in coordinating sessions during the Institute. We are very thankful to Mr. Dean
Brown and Mrs. Renhua Shen for their invaluable efforts in making the Institute a
success. A word of appreciation is also due to the members of the section chairmen
for their efforts in expediting the technical sessions.
Finally, our heartfelt thanks to all invited lecturers and authors, who provided the
substance of the Institute, and the participants for their attendance, questions, and
comments.
S. Kaka~
H. Yiincii
K. Hijikata
INTRODUCTION TO ASI ON COOLING OF ELECTRONIC SYSTEMS
Sadik kaka~
Department of Mechanical Engineering
University of Miami, Coral Gables, FL 33124
ABSTRACf. Cooling requirements in microelectronics are among the toughest barriers of
to develop faster, smaller, and still more reliable systems. During the Institute, studies and
review of papers on forced and natural air convection and liquid cooling (direct and indirect)
were presented. This Institute also address the need for further research on the heat
transfer in electronics. It is aimed to introduce various cooling methods in electronics and
to compare the advantages and disadvantages of various cooling techniques to see the extend
to which the designer can depend on them in the future.
1. Introduction
In the past three decades electronics has developed to surround all faces of modern life.
At the same time, with increasing number of applications reliability has become a real
crucial problem. The failure of a brand-new stereo may be tolerable, however a problem
in the sophisticated computers supporting vital systems of business, health and defense could
result in not only disruption of that service, but also disastrous events, perhaps, in terms of
human lives. Realizing the importance of the problem, much emphasis has been given to
the improvement of the reliability level as well as to the improvement of the electrical
performances of the electronic devices.
Improvement in the technology made it possible in early 1960s to integrate monolithic
circuits on a silicon chip. This enabled electronic manufacturers to build larger number of
smaller chips on smaller circuit boards. In the last twenty five years as chip sizes reduced
from approximately 100 to 1 ~m and the number of components in one chip increased
approximately from 1 to lOS (Figure 1)(1].
The chip is a rectangular slice of single crystal silicon which includes microscopic electronic
circuits.
A chip is housed in a package which contains the electrical leads. A package may contain
more than one chip and it is also termed as module. Packages are mounted on the printed
wiring board (PWB). The system is composed of the printed wiring boards.
Besides the increases in the scale of circuit integration, the ambitions desire towards faster
computers has led to the placement of integrated circuits (IC) packages closer together.
Hence, it has become common practice to assemble a large number of chips on a single
multilayer ceramic module and, in turn, to assemble multiple modules on a single board.
For large-scale computers, the heat removal from the chips is the major technical problem
in achieving higher data processing speeds.
Two dimensional assemblies are typical, however, three dimensional configurations are also
S. Kaka{: et al. (e ds. ), Cooling ofE lectronic Systems, 1-15.
© 1994 Kluwer Academic Publishers.
