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Imperial College Press
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Imperial College Press
57 Shelton Street
Covent Garden
London WC2H 9HE
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World Scientific Publishing Co. Pte. Ltd.
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British Library Catatoguing-in-Publication Data
A catalogue record for this book is available from the British Library.
BUILDING AERODYNAMICS
Copyright O 2001 by Imperial College Press
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For photocopying of material in this volume, please pay a copying fee through the Copyright
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ISBN 1-86094-187-7
Printed in Singapore.
Building Aerodynamics Acknowledgements. V
Acknowledgements
It is impossible to mention, or even be conscious of, all those people whose
work and contact have affected one's thinking or have implanted ideas which
have later flourished. To try to do so would produce omissions which one
would regret and which would never be fully redeemed. I would like, therefor,
to thank all who have educated me in Wind Engineering, and hope that they
think that I have done the subject justice in this book.
However, I would like to express my delight that Nick Cook and Wayne
Pearce have come to Bristol to carry on the work of Wind Engineering here,
and to thank them for all the help them have given me in the writing of this
book. I would like to thank Colin Wood for his help in filling the gaps in my
knowledge.
Several of the photographs, which are Crown Copyright, appear in the
text and do so by courtesy of the Director of the Building Research
Establishment.
I would like to thank Pauline, whose encouragement and backing made me
accept the contract to write this book in the first place, and who has kept me
in comfort while I finished it.
Building Aerodynamics Preface VM
Preface
This book is written specifically for the practicing Architect and Engineer.
The various interactions of the wind with buildings are considered in their
separate Chapters, each of which has an Introduction in which the interaction
is explained in general terms. Detailed data are presented in the rest of each
chapter explaining the extent of quantifiable information which can be made
available by the Wind Engineer to the Design Team so that the best
compromise between the requirements of wind and all the other competing
considerations can be made. Typical Tables and Figures from real situations
are presented as illustrations of all measurements and calculations. Theory
has been kept to a minimum, and is only presented when, in the author's
opinion, the analysis is not well known or is central to the argument.
It is hoped that the introductions to all the chapters will be of interest to
everyone, but to try to prevent a reader from being put off by long detailed
discussions which might not interest him, a Summary for each chapter is
presented under "Summaries" which suggests the parts of the chapter which
can be omitted by some readers without loss of envolvement in the team
discussions, whilst, at the same time, drawing the same reader's attention is to
those parts of the chapter which are appropriate to his detailed understanding
of the subject.
Although written for the practicing Architect and Engineer, it is
appropriate to the student Architect and Engineer because his needs are the
same.
Building Aerodynamics Contents IX
Contents
Summaries 1
1 The Wind 9
1.1 Global Circulation. 9
1.2 Extratropical Cyclones or Temperate Systems. 12
1.3 Strong Wind Speeds. 13
1.3.1. Mean Velocity Profile. 14
1.3.2. Turbulence Profile. 16
1.3.3. Spectral Density Function. 16
1.3.4. Length Scales of Turbulence. 18
1.4. Stability of the Atmosphere. 19
1.4.1. Definition. 19
1.4.2. Implications. 20
1.4.2.1. Inversions.
1.4.2.2. Stable and Unstable Atmospheres.
1.4.2.3. Application to Wind Tunnels.
1.5. Application to the Wind Engineer. 22
1.5.1. Displacement Height and Ground Roughness. 23
1.5.2. Reference Wind Speed. 24
1.5.3. Justification for Using Strong Wind Data. 26
1.5.3.1. Wind Loading.
1.5.3.2. Wind Environment.
Description:This book starts, by explaining briefly the origins of wind. It then proceeds to the normal forms of presentation for wind data, and explains how each is used in the appropriate analysis. The general aerodynamics of bluff bodies is explained in Chapter 2. Wind loading, wind environment, rain, ventil
