Basic Ship TheoryK.J. Rawson E.C volume 1 ppt

//SYS21///INTEGRA/BST/VOL1/REVISES 21-7-2001/BSTA01.3D ± 1 ± [1±24/24] 26.7.2001 4:11PM Basic Ship Theory //SYS21///INTEGRA/BST/VOL1/REVISES 21-7-2001/BSTA01.3D ± 2 ± [1±24/24] 26.7.2001 4:11PM //SYS21///INTEGRA/BST/VOL1/REVISES 21-7-2001/BSTA01.3D ± 3 ± [1±24/24] 26.7.2001 4:11PM Basic Ship Theory K.J. Rawson MSc, DEng, FEng, RCNC, FRINA, WhSch E.C. Tupper BSc, CEng, RCNC, FRINA, WhSch Fifth edition Volume 1 Chapters 1 to 9 Hydrostatics and Strength OXFOR D AUCKLAND BOST ON JOHANNESBURG MELBOURNE NEW DELHI //SYS21///INTEGRA/BST/VOL1/REVISES 21-7-2001/BSTA01.3D ± 4 ± [1±24/24] 26.7.2001 4:11PM Butterworth-Heinemann Linacre House, Jordan Hill, Oxford OX2 8DP 225 Wildwood Avenue, Woburn, MA 01801-2041 A division of Reed Educational and Professional Publishing Ltd A member of the Reed Elsevier plc group First published by Longman Group Limited 1968 Second edition 1976 (in two volumes) Third edition 1983 Fourth edition 1994 Fifth edition 2001 # K.J. Rawson and E.C. Tupper 2001 All rights reserved. No part of this publication may be reproduced in any material form (including photocopying or storing in any medium by electronic means and whether or not transiently or incidentally to some other use of this publication) without the written permission of the copyright holder except in accordance with the provisions of the Copyright, Designs and Patents Act 1988 or under the terms of a licence issued by the Copyright Licensing Agency Ltd, 90 Tottenham Court Road, London, England W1P 0LP. Applications for the copyright holder's written permission to reproduce any part of this publication should be addressed to the publishers British Library Cataloguing in Publication Data Rawson, K.J. (Kenneth John), 1926± Basic ship theory. ± 5th ed. Vol. 1, ch. 1±9: Hydrostatics and strength K.J. Rawson, E.C. Tupper 1. Naval architecture 2. Shipbuilding I. Title II. Tupper, E.C. (Eric Charles), 1928± 623.8 H 1 Library of Congress Cataloguing in Publication Data Rawson, K.J. Basic ship theory/K.J. Rawson, E.C. Tupper. ± 5th ed. p. cm. Contents: v.1. Hydrostatics and strength ± v.2. Ship dynamics and design. Includes bibliographical references and index. ISBN 0-7506-5396-5 (v.1: alk. paper) ± ISBN 0-7506-5397-3 (v.2: alk. paper) 1. Naval architecture I. Tupper, E.C. II. Title. VM156 .R37 2001 623.8 H 1±dc21 2001037513 ISBN 0 7506 5396 5 For information on all Butterworth-Heinemann publications visit our website at www.bh.com Typeset in India at Integra Software Services Pvt Ltd, Pondicherry, India 605005; www.integra-india.com Introduction Symbols and nomenclature 1 Art or science? 1.1 Authorities 2 Some tools 2.1 Basic geometric concepts 2.2 Properties of irregular shapes 2.3 Approximate integration 2.4 Computers 2.5 Appriximate formulae and rules 2.6 Statistics 2.7 Worked examples 2.8 Problems 3 Flotation and trim 3.1 Flotation 3.2 Hydrostatic data 3.3 Worked examples 3.4 Problems 4 Stability 4.1 Initial stability 4.2 Complete stability 4.3 Dynamical stability 4.4 Stability assessment 4.5 Problems 5 Hazards and protection 5.1 Flooding and collision 5.2 Safety of life at sea 5.3 Other hazards 5.4 Abnormal waves 5.5 Environmental pollution 5.6 Problems 6 The ship girder 6.1 The standard calculation 6.2 Material considerations 6.3 Conclusions 6.4 Problems 7 Structural design and analysis 7.1 Stiffened plating 7.2 Panels of plating 7.3 Frameworks 7.4 Finite element techniques 7.5 Realistic assessment of structral elements 7.6 Fittings 7.7 Problems 8 Launching and docking 8.1 Launching 8.2 Docking 8.3 Problems 9 The ship environment and human factors 9.1 The external environment. The sea 9.2 Waves 9.3 Climate 9.4 Physical limitations 9.5 The internal environment 9.6 Motions 9.7 The air 9.8 Lighting 9.9 Vibration and noise 9.10 Human factors 9.11 Problems Bibliography Answers to problems Index //SYS21///INTEGRA/BST/VOL1/REVISES 21-7-2001/BSTA01.3D ± 11 ± [1±24/24] 26.7.2001 4:11PM Foreword to the ®fth edition Over the last quarter of the last century there were many changes in the maritime scene. Ships may now be much larger; their speeds are generally higher; the crews have become drastically reduced; there are many dierent types (including hovercraft, multi-hull designs and so on); much quicker and more accurate assessments of stability, strength, manoeuvring, motions and powering are possible using complex computer programs; on-board computer systems help the operators; ferries carry many more vehicles and passengers; and so the list goes on. However, the fundamental concepts of naval architec- ture, which the authors set out when Basic Ship Theory was ®rst published, remain as valid as ever. As with many other branches of engineering, quite rapid advances have been made in ship design, production and operation. Many advances relate to the eectiveness (in terms of money, manpower and time) with which older proced- ures or methods can be accomplished. This is largely due to the greater eciency and lower cost of modern computers and proliferation of information available. Other advances are related to our fundamental understanding of naval architecture and the environment in which ships operate. These tend to be associated with the more advanced aspects of the subject: more complex programs for analysing structures, for example, which are not appropriate to a basic text book. The naval architect is aected not only by changes in technology but also by changes in society itself. Fashions change as do the concerns of the public, often stimulated by the press. Some tragic losses in the last few years of the twentieth century brought increased public concern for the safety of ships and those sailing in them, both passengers and crew. It must be recognized, of course, that increased safety usually means more cost so that a con¯ict between money and safety is to be expected. In spite of steps taken as a result of these experiences, there are, sadly, still many losses of ships, some quite large and some involving signi®cant loss of life. It remains important, therefore, to strive to improve still further the safety of ships and protection of the environment. Steady, if somewhat slow, progress is being made by the national and interna- tional bodies concerned. Public concern for the environment impacts upon ship design and operation. Thus, tankers must be designed to reduce the risk of oil spillage and more dangerous cargoes must receive special attention to protect the public and nature. Respect for the environment including discharges into the sea is an important aspect of de®ning risk through accident or irresponsible usage. A lot of information is now available on the Internet, including results of much research. Taking the Royal Institution of Naval Architects as an example xi //SYS21///INTEGRA/BST/VOL1/REVISES 21-7-2001/BSTA01.3D ± 12 ± [1±24/24] 26.7.2001 4:11PM of a learned society, its website makes available summaries of technical papers and enables members to join in the discussions of its technical groups. Other data is available in a compact form on CD-rom. Clearly anything that improves the amount and/or quality of information available to the naval architect is to be welcomed. However, it is considered that, for the present at any rate, there remains a need for basic text books. The two are complementary. A basic understanding of the subject is needed before information from the Internet can be used intelligently. In this edition we have maintained the objective of conveying principles and understanding to help student and practitioner in their work. The authors have again been in a slight dilemma in deciding just how far to go in the subjects of each chapter. It is tempting to load the books with theories which have become more and more advanced. What has been done is to provide a glimpse into developments and advanced work with which students and practitioners must become familiar. Towards the end of each chapter a section giving an outline of how matters are developing has been included which will help to lead students, with the aid of the Internet, to all relevant references. Some web site addresses have also been given. It must be appreciated that standards change continually, as do the titles of organizations. Every attempt has been made to include the latest at the time of writing but the reader should always check source documents to see whether they still apply in detail at the time they are to be used. What the reader can rely on is that the principles underlying such standards will still be relevant. 2001 KJR ECT xii Foreword to the fifth edition //SYS21///INTEGRA/BST/VOL1/REVISES 21-7-2001/BSTA01.3D ± 13 ± [1±24/24] 26.7.2001 4:11PM Acknowledgements The authors have deliberately refrained from quoting a large number of refer- ences. However, we wish to acknowledge the contributions of many practi- tioners and research workers to our understanding of naval architecture, upon whose work we have drawn. Many will be well known to any student of engineering. Those early engineers in the ®eld who set the fundamentals of the subject, such as Bernoulli, Reynolds, the Froudes, Taylor, Timoshenko, Southwell and Simpson, are mentioned in the text because their names are synonymous with sections of naval architecture. Others have developed our understanding, with more precise and compre- hensive methods and theories as technology has advanced and the ability to carry out complex computations improved. Some notable workers are not quoted as their work has been too advanced for a book of this nature. We are indebted to a number of organizations which have allowed us to draw upon their publications, transactions, journals and conference proceedings. This has enabled us to illustrate and quantify some of the phenomena dis- cussed. These include the learned societies, such as the Royal Institution of Naval Architects and the Society of Naval Architects and Marine Engineers; research establishments, such as the Defence Evaluation and Research Agency, the Taylor Model Basin, British Maritime Technology and MARIN; the classi®cation societies; and Government departments such as the Ministry of Defence and the Department of the Environment, Transport and the Regions; publications such as those of the International Maritime Organisation and the International Towing Tank Conferences. xiii [...]... 21- 7-20 01/ BSTA 01. 3D ± 18 ± [1 24/24] 26.7.20 01 4 :11 PM xviii Introduction Pre®xes to denote multiples and sub-multiples to be axed to the names of units are: Factor by which the unit is multiplied Prefix Symbol 1 000 000 000 000 =10 12 1 000 000 000 =10 9 1 000 000 =10 6 1 000 =10 3 10 0 =10 2 10 =10 1 0 :1= 10 1 0: 01= 10À2 0:0 01= 10À3 0:000 0 01= 10À6 0:000 000 0 01= 10À9 0:000 000 000 0 01= 10 12 0:000 000 000 000 0 01= 10 15 ... Length 1 yd 1 ft 1 in 1 mile 1 nautical mile (UK) 1 nautical mile (International) 0. 914 4 m 0.3048 m 0.0254 m 16 09.344 m 18 53 .18 m Area 1 in2 1 ft2 1 yd2 1 mile2 645 :16  10 À6 m2 0:092903 m2 0:83 612 7 m2 2:58999  10 6 m2 Volume 1 in3 1 ft3 1 UK gal 16 :38 71  10 À6 m3 0:028 316 8 m3 0:004546092 m3 ˆ 4:546092 litres Velocity 1 ft=s 1 mile=hr 1 knot (UK) 1 knot (International) 0:3048 m=s 0:44704 m=s ; 1: 60934... km=hr 0: 514 77 m=s ; 1: 85 318 km=hr 0: 514 44 m=s ; 1: 852 km=hr Standard acceleration, g Mass 32 :17 4 ft=s2 1 lb 1 ton 9:80665 m=s2 0:45359237 kg 10 16:05 kg ˆ 1: 016 05 tonnes Mass density 1 lb=in3 1 lb=ft3 27:6799  10 3 kg=m3 16 : 018 5 kg=m3 Force 1 pdl 1 lbf 0 .13 8255 N 4.44822 N Pressure 1 lbf=in2 18 52 m 6894:76 N=m2 0:0689476 bars 2 Stress 1 tonf=in 15 :4443  10 6 N=m2 15 :443 MPa or N=mm2 Energy 1 ft pdl 1 ft... water 64 lb=ft 35 ft3 =ton 1: 0252 tonne=m 0:9754 m3 =tonne 1: 025 tonne=m3 0:975 m3 =tonne Mass density fresh water 62:2 lb=ft3 36 ft3 =ton 0:9964 tonne=m3 1: 0033 m3 =tonne 1: 0 tonne=m3 1: 0 m3 =tonne Young's modulus E (steel) 13 ,500 tonf=in2 2:0855  10 7 N=cm2 209 GN=m2 or GPa Atmospheric pressure 14 :7 lbf=in2 10 1,353 N=m2 10 :13 53 N=cm2 10 5 N=m2 or Pa or 1. 0 bar 1: 025 Aw (tonnef=m) 1: 025 Aw tonnef=m W b... water) (Units of tonf and feet) Weight density: Salt water Fresh water Speci®c volume: Salt water Fresh water ÁGML tonf ft in 12 L 1. 016 tonne 0. 01 MN=m3 0.0098 MN=m3 99.5 m3 =MN 10 2.0 m3 =MN //SYS 21/ //INTEGRA/BST/VOL1/REVISES 21- 7-20 01/ BSTA 01. 3D ± 19 ± [1 24/24] 26.7.20 01 4 :11 PM Introduction xix Of particular signi®cance to the naval architect are the units used for displacement, density and stress... frequency volume in general xx //SYS 21/ //INTEGRA/BST/VOL1/REVISES 21- 7-20 01/ BSTA 01. 3D ± 21 ± [1 24/24] 26.7.20 01 4 :11 PM Symbols and nomenclature xxi GEOMETRY OF SHIP AM AW Ax B BM CB CM CP CVP CWP D F GM GML IL IP IT L LOA LPP LWL S T Á  r Æ midship section area waterplane area maximum transverse section area beam or moulded breadth metacentre above centre of buoyancy block coecient midship section... (m2 ) w 3 2 Aw (m ) 10 0:52 Aw(N=cm) 10 ,052 Aw (N=m) 10 4 Aw (N=m) One metre trim moment, tonnef m , Á in tonnef ) (Á in MN or m   ÁGML MN m m L   ÁGML MN m m L Force displacement Á 1 tonf 1. 016 05 tonnef 9964.02N 1. 016 tonnef 9964 N Mass displacement Æ 1 ton 1. 016 05 tonne NPC NPM b b b b Y MCT 1HH (salt water) (Units of tonf and feet) Weight density: Salt water Fresh water Speci®c volume: Salt water... a function of p, L and V, e.g mH ˆ m= 1 L3 , xH ˆ x= 1 L2 V 2 , LH ˆ L= 1 L3 V 2 2 2 2 (c) A lower case subscript is used to denote the denominator of a partial derivative, e.g Yu ˆ @Y=@u • (d) For derivatives with respect to time the dot notation is used, e.g x ˆ dx=dt //SYS 21/ //INTEGRA/BST/VOL1/REVISES 21- 7-20 01/ BSTC 01. 3D ± 1 ± [1 6/6] 26.7.20 01 4 :12 PM 1 Art or science? Many thousands of years... transverse plane from the top of the ¯at keel to the design waterline If unspeci®ed, it refers to amidships The draught amidships is the mean draught unless the mean draught is referred directly to draught mark readings //SYS 21/ //INTEGRA/BST/VOL1/REVISES 21- 7-20 01/ BSTC02.3D ± 10 ± [7± 51/ 45] 26.7.20 01 4 :13 PM 10 Basic ship theory Fig 2.4 Moulded and displacement lines Fig 2.5 The moulded depth is the perpendicular... lbf 1 cal 1 Btu 0.04 214 01 J 1. 35582 J 4 .18 68 J 10 55.06 J Power 1 hp 745.700 W Temperature 1 Rankine unit 1 Fahrenheit unit 5=9 Kelvin unit 5=9 Celsius unit Note that, while multiples of the denominators are preferred, the engineering industry has generally adopted N=mm2 for stress instead of MN=m2 which has, of course, the same numerical value and are the same as MPa //SYS 21/ //INTEGRA/BST/VOL1/REVISES . fraction C D drag coe. C L lift coe. C T speci c total resistance coe. C W speci c wave-making resistance coe. D drag force F n Froude number I idle resistance J advance number of propeller K Q torque coe. K T thrust. m=s 2 Work, energy joule J  Nm Power watt W  J= s Electric charge coulomb C  As Electric potential volt V  W=A Electric capacitance farad F  As=V Electric resistance ohm   V=A Frequency hertz. both directions; for example, the choice of machinery to serve speed and endurance re¯ects back on the volume required and the architecture of the ship which aects safety and structure. And so