BASIC NAVAL ARCHITECTURE

by

KENNETH C. BARNABY a.B.E .. D,Sc., A.C,G,I.

An H onorary Vice-President of the !J.oyal In.rtitution of Nallai Architects

FrouJe Mu/allist Parsons MeJal1i.st

Author of1nstirution of Naval Architects 1860-1960 (AlIen and Unwin)

Author of 100 Years of Specialized Shipbuilding and Engineering (HutelU.son)

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HUTCHINSON SCIENTIFIC AND TECHNICAL

LONDON

--------------------_._-

CONTENTS

EXTRACT FROM PREFACE TO FIRST EDITION

PREFACE TO FIFTH EDITION

I. INTRODUCTORY

I. Ship Terms. 2. Symbols and Notation. 3. Order of Presentation. 4. Dimensions and Rules. 5. Appearance.

n. HULL FORM-DELINEATION AND GEOMETRY

6. Definitions. 7. Lines Drawing and Fairing the Lines 8. Conic and Cylindrical Development 9. Sheer Line.

1II. THE CALCULATION OF AREAS, MOMENTS, ETC.

10. Mensuration Rules. 11. Trapezoidal and Mean Ordinate Rules.

Page 13 13

15 15 15 16 16 17

19 19 28

29 32

34 34 35

12. Mathematical Basis for the Simpson and Tchebycheff Rules.

13. Simpson's First Rule. 14. Simpson's Second Rule. 15. "5 + 8 - I" Rule. 16. Durand's Rules. 17. Tchebycheff's Rules. 18. Half Spacing. 19. Effect of "Knuckles" and End Correction. 20. Choice and Accuracy of Rules. 21. The Planimeter. . 22. The Integrator. 23. The Integraph. 24. The Calculation of First Moments and Moments of

Inertia. 25 . "3 + 10 - I" Rule for Moments. 26. Radial or "Polar" Integration.

IV. FLUIDS AT REST-FIRST PRINCIPLES

27. Pressure Head. 28. The Density of Sea Water.

3

36 37 38

39 40

41

43 43 44 45 46 48

CONTENTS

29. Total Pressure and Centre of Pressure. 5~ 30. Calculation of the Centre of Pressure. 5' 3" Centre of Pressure on Inclined Plane. 6: )2. Floating Structures-Principle of Archimedes. 6: 33. Buoyancy, Pressure and Volume. 6,

V. TRANSVERSE STABILITY 6,

34. The Metacentre and Axes of Inclination. 6< 35. Heeling and Righting Moments. 6' 36. Initial Stability and Metacentric Height. 6: 37. Free Surface. 6< 38. Inclining Experiment. 7 39. Stability at Large Angles. T 40. Layer Correction. 7, 4'. Barnes' Method for Stability. 7' 42. Stability by Integrator. 8, 43. Cross Curves of Stability. 8 44. Alternative Methods for Transverse Stability. 8, 45. Dynamical Stability. 8,

VI. TRIM, LONGITUDINAL STABILITY AND ADDITION OF

WEIGHTS, ETC. 8, 46. Principal Axes of Inclination. 8, 47. Trim and Trimming Moments. 8' 48. Longitudinal Metacentre. 8, 49. Moment to Change Trim One Inch. 9' 50. Formula for Moment to Change Trim One Inch. 9: p. The Addition of Weights. 9 51. Suspended Weights. 9: 53. Movable Weights. 9: 54. Stability when Grounding or Docking. 9 55. The Stability of Submarines. 9.

VII. HYDROSTATIC CURVES AND THE DISPLACEMENT

SHEET

56. Displacement Calculation. 57. Vertical Centre of Buoyancy (V.c.B.). 58. Longitudinal Centre of Buoyancy (L.C.B.). 59. Tons Per Inch (T.P.I.). 60. Transverse Metacentre from Sheet.

9' 9'

fOC

IOC

10:

10]

CONTENTS

61. Longitudinal Metacentre from Sheet and Centre of Flotation. 10!

62. Moment to Change Trim One Inch from Sheet. 103 63. Change of Displacement for One Foot Change of

Trim at Perpendiculars. 103 64. The Plotting of Hydrostatic Curves. 103 65. Morrish Formula. 105 66. Bonjean Curves. 105 67. Wetted Surface by Measurement. 107 68. Wetted Surface by Formula. 107 69. Wetted Surface of Abnormally Shallow-Draught

Forms. 108

VI!!. RULES FOR FREEBOARD, SUBDIVISION AND

ST ABILITY 109

70. National and International Regulations. 109 71. Load Line Markings. 109 72. Minimum Summer Freeboard. 1I0 73. Standard Sheer and Sheer Difference Correction. Ill. 74. Round of Beam Correction. 113 75. Nomenclature and Dimensions, etc., in Freeboard

and Subdivision Rules. II 3 76. The Criterion of Service Numeral (C,). 1I6 77. Factor of Subdivision. "7 78. Use of Standard Floodable Length Curve. 119

79. Correction of Standard Curves. 120 80. Modifications for Restricted Plying Limits. 120 81. Permeability Interpolation Formula. 122-82. Basic Principles and Equations for Floodable Length

Curves. 122-83. Explanation of Form Corrections to Floodable Length

Curves. 125 84. Special Rules concerning Subdivision. 127 85. Added Weight Method for Flooded Stability. 11.8 86. Lost Buoyancy Method for Flooded Stabiliry. 11.9 87. Flooded Metacentric Height and Angle of Heel. 130 88. Intact Buoyancy and Angle of Heel. 131 89. Stabiliry Requirements. 132

IX. FLUIDS IN MOTION-FIRST PRINCIPLES 135 90. Currents and Streams. 135 91. Dimensions of Measurement Units. 135

!

CONTENTS

92. Total Energy of Water. 140 93. Bemoulli's Steady Motion Theorem. '4' 94. Limitations of Bemoulli's Theorem. 144 95. Venturi Tube and Meter. 145 96. Venturi Effect with Ships in Restricted Waterways. 146 97. Magnus Effect and "Circulation" '47 98. Pitot Tube. '49 99. Streamline Flow around Vessel in Open WateI. 150

100. Impact of Water. 151

X. FLUIDS IN MOTION-GRAVITY AND VISCOSITY

EFFECTS

101. Real Fluids. 102. Viscosity. 103. Effect of Temperature on Viscosity. 104. Kinematic Viscosity. 105. Comparison with Air. 106. Pressure Conditions on Inclined Flat Plate. 107. Flow Pattern at Inclined Flat Plate. 108. Formulae for Pressures on Plates Inclined at Various

Angles. '09. Eddy-making Resistance from Blunt-Ended Fittings. 110. Laws of Dimensional Similarity and Comparison. 11 I. Reynolds Number and Viscous Resistance. 112. Froude Number and Speed/Length Ratio. "3' Combined Viscosity and Gravity Resistance. "4. Froude's Method and Law of Comparison. "5. The Validity of Froude's Assumptions. 116. Presentation of Form and Resistance Data-

Froude's Constants. II7. American Notation for Resistance Data. 118. The Admiralty Constant and "Circular C" 119. Reynolds Number for Propellers and Sails

XI. THE PROPERTIES OF WAVES 173

120. Types of Waves-Pressure Waves. '73 121. Ripples or "Capillary Waves". '73 122. Waves of Oscillation-me Trochoidal Theory in

Deep Water. '74 123. Dimensions of Actual Ocean Waves. 179 126,. Gtou\, Velocity of Wave Trains. Igl 12\. Shallow-Water Waves and Waves of Translation. 18.

G

CONTENTS

XII. SURFACE FRICTION 187

126. F roude's Experiments. 187

127. Reynolds' Experiments. 189

128. Gebers' Experiments. 190

11.9. Laminar and Transitional Flow. 191.

130. Boundary Layer Flow Conditions. 193

131. "Smooth-Turbulent" Friction Lines. 195

131.. Boundary Layer Thickness. 1.01

133. Effect of Rough Surfaces. 201

134. Comparison of Froude's Constants with Modem Formulations. 1.04

135. Calculation of Frictional Resistance and Horse-power. 205

136. Temperature Correction for Surface Friction. 1.06

137. Effect of Fouling. 206

138. Form Effect. 207

139. F rictional Wake. 208 140. Summary of Friction Calculations. 209

Xlii. RESIDUAL RESISTANCE AND FORM 1.11

141. Wave Causation. 211

141.. Growth of Wave-Making Resistance. 212

143. Spacing of Wave Systems. 1.14 144. Residuary Resistance from Standard Series Tests. 217

145. Summary of Taylor Results. 1.18

146. Modem Improved Forms-General Considerations. 222

147. Midship Section Coefficient and Area. 21.3

'48. Parallel Middle Body and Length of Entry. 224

149. Angle of Entrance. 225 150. Curve of Transverse Areas. 226

IjI. Maier-Form Bow. 227

152. Bulbous Bows and "Waveless" Forms 228

153. Residuary Resistance of Destroyer Types. 229

154. Residuary Resistance of Motor Launches. 229

155. Residuary Resistance of Fast Round-Bottom Launches. 230

XIV. EXPERIMENTAL TESTING TANKS OR "MODEL BASINS" 232

156. Types and Dimensions. 232

157. The Scaling Up of Tank Results. 235 158. Turbulence Stimulation and Tank "Storms". 238

159. Telfer Method with "Geosims" 240

7

CONTENTS

XV. AIR RESISTANCE AND SAIL PROPULSION 242

lOO. Comparison of Air and Water Resistance. 242 161. True and Relative or "Apparent" Wind. 244 162. Air Resistance of Ships. 245 163. Sail Propulsion. 249 164. The "Gimcrack" Sail Coefficients. 2jl 165. Sail Plans. 256 166. Centre of Effort and "Lead". 257 167. Resistance and Balance of Sailing Vessels. 259 168. Sail Area and Power to Carry Sail. 261 169. Multi-hulled Vessels. 262

XVI. MARINE PROPELLERS 265 170. Jet Propulsion and Fluid Efficiency. 265 171. Apparent and Real Slip. 268 172. Wake Factors and Wake Percentage. 269 173. Paddle Wheels. 270 174. Volpich and Bridge Method of Paddle Wheel Design. 272 175. Stern Wheels. 274 176. Fixed and Feathering Floats. 275 177. Screw Propellers-Theories and Methods of Design. 277 178. Propeller Notation and Constants. 278 179. Propellers and the Law of Similarity. 285 180. Interaction of Hull and Propeller. 287 181. Variation of Hull Efficiency, Thrust Deduction and

Wake. 289 182. The Calculation of Thrust Loads and Bollard Pull 292 183. Kort Nozzles. 298 184. Lateral Thrust Units. 299 185. Blade Area and Numher of Blades. 301 186. Cavitation and High Thrust Loading. 303 187. Fully Cavitating Propellers. 308 188. Examples of Propeller Design. 311

189. Handing of Propellers. 312

190. Strength, Thickness and Materials of Propeller Blades. 313 191. Circulation or Vortex Theory. 315

XVII. THE POWERING OF VESSELS 32C

192. Powering Methods. 320

193. Propulsive Efficiency. 323 194. The Admiralty Constant. 325 195. Direct Power Curves. 327

XVJll.

XIX.

xx.

CONTENTS

196. The "K" Method of Powering. 32.8 197. Tow-rope Horse Power for Dumb Barges, etc. 330 198. Shallow Water Resistance. 331

THE DESIGN AND POWERING OF PLANING CRAFT

'99. The Planing Principle. 2.00. Measurement Coefficients for Planing Hulls. 2.01. Lift and Centre of Pressure. 2.02. The U.S.T.M.B. Series 62 Tests. 203. The Powering of Hard Chine Stepless Hulls. 2.04. Stepped Hulls. 2.05. The Hydrofoil Boat.

MOTION IN A SEAWAY

1.06. Types of Motion. 2.07. Forces Due to Rolling and Pitching. 2.08. Period of Encounter and Forced Rolling and Pitching. 1.09. Relation of Period of Encounter to Narural Period. 210. Steering and Manceuvring. 211 . T uming Circles. 2.12.. Rudder Areas and Pressures. 1.13. Balanced Rudders, Strength of Rudders, etc. 2.14. Heel when Turning. 2.15. Steering by Propellers. 1.16. Flettner, Kitchen and Tutin Rudders. 217. Summary of Steering and Course-Keeping. 2.18. Anti-Rolling Devices. 1.19. Seaworthiness and Proportions. 2.20. The Starting and Acceleration of Ships. 22.1. Stopping, Astern Way and Propeller Drag.

THE STRENGTH OF SHIPS

1.1.2.. Classification Rules. 223. Beam Theory, Bending and Shear Stresses, Deflec-

tions, etc. 2.24. Direct Determination of Bending Moment. 1.2.5. Standard Approximation for Bending Moment. 2.2.6. Still Water and Wave Bending Moments. 1.1.7. Stress and Modulus Calculations. 22.8. Working Stresses. 229. Local!Strength.

336

336 339 340 345 347 349 3P

35'S

356 360 361 361. 364 364 366 3~ 371 371. 373 374 375 380 381

384

388

388

390 393 397 398 401 402 40 3 9

CONTENTS

Z30' Measurement of Static Stresses, Strains and Deflec-tions. 404

z 3" Dynamic Stresses. . 406

z p. Expansion Joints. 407 233. Composite Constf\lction. 40 7

XXI. THE VIBRATION OF SHIPS 409 409 410

421

234. Modes of Vibration for Uniform Bar. z 35. The Vertical Vibration of Ships. 236. The Horizontal Vibration of Ships. 237. Precautions against Vibration. 423

XXII. LAUNCHING CALCULATIONS 42)

238. General Principles. 4'S 239. Launching Curves. 416 240. Way-End Pressures. 418 241. Launching Particulars. 430 242. Releasing Arrangements and Coefficient of Friction. 434 243. Dynamic Effects. 436 244. Broadside Launching. 437

245. Marine Railways. 438

XXIlI. MATERIALS OF CONSTRUCTION 439

246. Wood v. Steel. 439

247. Structure and Growth of Timber. 440 248. Annual Growth Rings. 440 249. Maturing, Seasoning and Moisture Content. 442 250. Time of Felling and Methods of Conversion. 443 lSI. Qualities Required for Shipbuilding Timbers. 444 2)2. Plywoods and Laminated Construction. 444

2)3. Qualities ofIndividual Woods. 445 2\4. Plastic Hulls. 45 I

2)). Steels. 453 2S6. Aluminium Alloys. 453 2\7. Galvanic Corrosion. 454 258. Precautions against Galvanic Corrosion. 460 259. Local Corrosion. 462

XXIV. SOME DESIGN PROBLEMS 465 zoo. Tonnage Regulations. 465 261. Weight Estimates. 468 262. Special Types. 470

263. Computers. 473

10

264. Ram bows APPENDIX

CONTENTS

265. Polar Moment ofInertia of Propeller. 266. Calculation of Propeller Stresses.

NUMBERS AND CONVERSION FACTORS

NAME INDEX

SUBJECT INDEX AND GLOSSARY

LIST OF ABBREVIATIONS

A.T.T.C.-American Towing Tank Conference.

B.S.R.A.-The British Ship Research Association.

D.T.M.B.-David Taylor Model Basin.

493

495

499

LE.S.S.-Transactions of the Institution of Engineers and Shipbuilders in Scotland.

I.N.A.-Transactions of the Royal Institution of Naval Architects.

LT.T.C.-International Towing Tank Conference.

N.A.C.A.-National Advisory Committee for Aeronautics, U.S.A.

N.E.C.-Transactions of the North-East Coast Institution of Engineers and Shipbuilders.

N.P.L.-The National Physical Laboratory, Teddington and Feltham.

S.N.A.M.E.-Transactions of the Society of Naval Architects and Marine Engineers.

U.S.N.-United States Navy.

Il

SUBJECT INDEX AND GLOSSARY Tlte numhers reftt to pages, not articles

Acceleration (definition), 137(<1) Acceleration of Ships, 381 Added weight method for stabili,y, 128 Addition of weights, 91 Admiralty constant, 171, J2~ Advance, 365 --, speed of, 2.69 Air coefficients, 155 -- data, 138(,1) -- resistance of ships, 245 Alexander formula for block coefficient,

221

Aluminium alloys, 407, 452, 453- 60 Angle of entrance, 19, Table 24, 225 Angular velocity, 137(C) Annual rings, 440 Anode, Figs. 132,133, 4P- 46) Anti-fouling, 2.06 -- rolling devices, 375-80 Apparent slip, 2.68 --wind,2.44 Appearance, 17 Apron (a sh.aped piece of timher ahaft the

sum), 15 Arc.form, 224

Archimedes, Principle of, 62. Ardency, 257, Fig. 88 Areas, Curve of, 2.1, 226

Ash, 440, 44 5 Aspect ratio, 19, Fig. 64, 160 Atmosphere, Standard, 138 Attwood's formula for stability, 67, 74 Autumn wood, 441, Fig. ll.9 Axes of inclination, 66, 86

Balsa wood, 440, 44 5 Barge form, 330 Bamcs' method, 75-80 Beam ,heory, 390

Bearing pressure (launching), 430, Fig. 124

Beating (sailing to windwarJ), 149 Beaufort Scale, Fig. 67, 184, Table 1.7,

243 Beaufoy's formula (rudders), 161, 368 Beech,446 Belly (sails), 256 Bending moments, 393-402 Benjamin's meulOd (s,abiliry), 84 Bernoulli's theorem, 141-5 Bias corrector, 31), 374 Bilge diagonals, 19 -- keel, 19, 376 Binary notation, 474 Birch,446 B1asius formula, Fig. <>9, J 92 Block coefficient, 19, 114, 221 Blockage, 234 Blom method (s,ability), 84 "B.M." (metacerttric radius), 66

Body plan, 20

Bollard pull, 292-8, Tables », 33 Bonjean curves, 105

Bonnet (additional ca/was below the foot of a sail), 15

Bossing, 20, 290 Boundary layer, Fig. 61,158 ---- thickness, 193 Bow lines, 20

Boxing the heart, Fig. 130,443 Breadth for freeboard, 113 Broad reach (sailing with tne wind abaft the

kam, between. running and reaelting),

249 Broadside launching, 437 Budget plate (see under Deadwood),

21

Bulbous bows, 228, 475 Bulk modulus, 144

499

SUBJECT INDEX AND GLOSSARY

Buoyancy, 63, 100, 1;1

Burbling, 158 Butt (of timber), 440 Buttocks, :10

(t', ("circular c"), 170 Camber, 20

Cambered ways, 432, Fig. 11.7 Camhium, 440, 442 Camels, 62-Camphor wood, 446 Canal barges, 330 Cant frames, 20

Capillary waves, 173 Cascade effect, 278 Catamarans, 263 Cat-harpings (small ropes hunching up the

lee shrouds), 15 Cathode, Figs. 132, 133 Cathodic protection, 455-463 Cavitation, 286, 303-3 II -- number, 286 -- tunnel, 287, 304 Cedar, 446 Centre of buoyancy, 21, 62, 66, 100-1

- -- effort, 257 ---- flotation, 86-8 101, 124 ---- lateral resistance, 2) 8 ---- pressure, 57, 59,61 Centrifugal force, 140(n) Change of trim, 87, 103, 12.4 Channel steamers, 2.2.6, 327, ;60 Checking (launching), 436 Chine, 21, )36 Circular constants, 169 -- measure, 177 Circulation, '47, 3 I 5 Classification rules, 385 Clinker, or denchcr built (boathuildinB

with overlapped strake.r in lieu of flush carve! planks), 448

Coefficient of friction (launching), 434 ---- reduction (rudders), 368 -- --- resistance, 170(c) ---- roughness, 20!

---- surface friction, 187 Columbian Pine (see under Oregon Pine)

500

Comparison, Law of"-Froude's, 166 ------ -Propellers, Table 31,

1.80,286 ------ -Viscosity, 164 Composite construction, 4<>7 Computer Usmoothing", 474 Computers, 473 Cone propeller, 140

Conic development, 2.9 Contra-propener, 2.78, 374 Conversion facrors-oil, Table 5,58 ---- -water, Table 4,58 Conversion of lumber, 443 Copper sheathing, 460 Corrosion, 454 Course keeping, 374 Creep resistance (launching), 434 Criterion of service, 116

Critical velocity of water, 189 Cross curves of stability, 81 Cruiser stem, 227 Currents (hydrodynamic), 135 Cut-up, 21 CylindriC4l1 development, 29 Cypress, 446

Damping coefficients, Table 48, 375 Datum planes, 21 D eadrise, 2t, 338 Dcadwater, 173 Deadwood, 11

- - in timber, 442 D ecremental equation, 375 D educted spaces, 465 Deflection of beams, 390 Denny-Brown Stabiliser, Fig. 119, 378 -- Mumford formula (wetted surface),

108 D ensity, 15 , 57, 1;8 Denudation of floa ts, 162. Depth for freeboard, "3(c) Depth and fullness, corrections for, I I I

Design data, Table 5 8, 469 D estroyers, Admiralty constants, Table 39,

327 --, propulsive efficiency, 219, Jl.4 --, residuary resistance, Table 25, 229 De-zincification, 460

SUBJECT INDEX AND GLOSSARY

Diagonals, 22

Dimensional similarity, 163 Dimensions and rules, 16 -- of measurement units, 135-40 Dipping, 3,6 I)isplacement calculations and Sheet, :z:z,

Table 10, 96-100

Displacement ratio, 170, 218 Docking stability, 93 Dogshores, 425, 434 Douglas fir, 446 Drag coefficient, 157, .251, Fig. 119,

379 -- induced, 242

-- profile, 242

Drags (launching), 436 Draught for freeboard, 114(J) Draught marks, 22, 62

Dry rot, 442 Durand's Rules, 40 Dynamic effects (launching), 436 -- pressure, 242

-- stresses, 406 Dynamical similarity, 164 -- stability, 68, 84

-- --, T orquay, 187, 231. Extrapolator, Tclfer's, '99

Factor of subdivision, 117

F<lirings,22 Feathering padclIes, 275 Felling (of trees), 443 Ferries, 471 Fetch (of waves), 180

Fibre-glass, 451

Fir, 449 First muments, 49 "Five-eight-one rule", 39 Fixed Roats, 27S

Flare, 22

Flettner rudder, J 73 Floating docks, 473 Floodable length, 116, 119 Flooded stabili ty, 128

Flow pattern and coefficients, 157 Fluid efficiency, 2.65 Force (definition), 138 (g) Form effect, 2.07 Fouling, 206

Free surface, 69, rp, 2. II Eddy making, 161, 2.22 ---- corrcction, 7( Electro-chemical series, 455 Frccboard (definition), 22

Electrolysis, 4H -- markings, 109 Elm, 446 -- ratio, I I S Encounter, period of, 361 -- rules, 11<r4 End correction (mensuration), 43 -- standard, I t o Energy of water, 140 Friction drag, Table 3, 56 ---- waves, t79 --launching, 434 Entrance, 22, 22.4 --lines, Table J9, 195-210, Table -- angle, 19, 225 66,489 Epochal hull fonn, 228 Friction hurse-power, 205

"E.T.T. formula" (planing hulls), 342 -- summary, 109

Exempted spaces, 465 --, surface, 187-2 [ 0

Expansion joints, 407 --, temperature correction, 206 Experimental tanks, 232 --, wake, 208 ----, Carderock, 232 Froude number, I6S -- --, Clydebank, 240 Froudc's assumptions, validi ty, of 168 -- ---, Fort Steyne, 232, 349 -- constants (frictional), Table 17, 187, -- --, Haslar, 188,239 Table 18, 18& -- --, Stevens,* 1):1, lop, 34I ---- (non-dimensional), 169 -- --, Sr. Albans, 22) -- formula (rudder), t61

*Now termed the "Davidson Laboratory, Stevens Instirute" ,01

SUBJECT INDEX AND GLOSSARY

Froude·s assumptions (wetted surface), 108

--law of comparison, 166

Gaboon, 447 Galvanic corrosion, 454 Gebers' experiments, 190

Geosims (Telfer method), 240

Gimcrack coefficients, Table, 28, 252 Glass fibre, 4S [ HG.M." (transverse metacentric height), 66-

9S, 132 , 380- 1

Gradient wind, 182,254 Greenheart, 447 Gyroscopic stabiliser, 378 ffG.Z." (righting lever), 66-9S

Half spacing, 43 Hard chine hulls, 336-35' Hardwoods, 440 Heartwood, 442. Heaving period, 3S7 Heel when turning, 341, 371 -- (wind pressure), 261

Heeling angle and moment, 67, 130, 261 Hele-Shaw method (streamlines), [SO Hogging stresses, 394 Hooke's law, 390 Hoop effect, 248, 25'4 Horse (har or rail on which a sheet travels),

IS Hounds (mast projections carrying shroud

attachments), I; Hull efficiency, 287 Hydraulic gradient, 189 -- propulsion, 26;, 300 -- smoothness, :20:2

"Hydrofin" (Hook type), 3D Hydrofoil boat, The, 3S1 Hydrogap rudder, 367 Hydrostatic curves, 103 -- pressure, 56--65

Impact of water, 152 Impulse (definition), I}8(f)

\0.

Inclining experiment, 71 Inertia and moments of inertia, 139 Inflow of water, 141 Inside multipliers (mensuration), 34 Intact buoyancy, 129 Integraph, 48 Integrator, 46, 80 Interaction, hull and propeller, 287 Interpolation formula (permeability), 111

---- (subdivision), 118 Iroko, 447 HIron bacteria", 464 "LT.T.e. formula", Table 19, '00, Table

66,489

'T' (propeller constant), 2.80 "J~class" yacht, 225, Table 29, 200-1 Jarrah,448 Jet propulsion, 265 Joessel's formula (rudder), 161

® (speed constant), 169(6) HK" method of powering, 328, Table 40,

Fig. tU, 347 Karri,448 Kauri,448 Kinematic viscosity, 115, Table 14, 156 Kinetic energy, 139(/) Kirsten~Boeing propeller, 373 Kitchen rudder, 373 Knot, 137(6) Knuckle, 23, 43 Kart nozzle, 298

© (speed constant), 169(6) Laminae film (or suh~layer), 202 -- flow, 189, 192 Laminated construction, 444 Larch, 441, 448 Late wood, Fig. 129,440 Lateral resistance, centre of, 257 -- thrust units, 299 Launching calculations, 402

Layer correction, 73, Fig. :28 "Lead" (sails), Fig. 88, 217

-,

1 Lead keel, 460 Lee helm, 257 Leeboards, 262

Leech (or leach), 256 Leeway,2p.

SUBJECT INDEX AND GLOSSARY

"Metacentricshelf7l, 258, 260

Midship section coefficient, 2.), .11.)

Mill scale, 462

Length for freeboard rules, I I J(a) Lift, 157, 2)0, Fig. 98, 305, Fig. 106,

337, Fig. 108, 342, Fig. 11), 352 Lignum vitae, 448 Lines plan, 2) , Fig. 0, 27, 28

List, 86, I J r Lizard Ca snort length of rope with. an eye at

one end), I)

Load Line, J 10

Loblolly pine, 450 Local corrosion, 46:2--- strength, 403 Locked-up stress, 40)

Longitudinal centre of buoyancy, 89, 100

-- metacentre, 89, 101

-- modulus, 401

-- stability, 86-95 Lost buoyancy method, 129

Lundberg method (effective depth), 413

® (length coefficient), 169(a) Magnesium, 461 Magnus effect, 147, 168 Mahogany, 448 Maier bow, 217, 238 Manganese bronze, 314, 460 Manceuvring with twin screws, 372 Margin line, 1 14

Marine railways, 438 Mass (definition), 135 -- correction factor, 414 -- density, '36, IJ8(h) Materials of construction, 439 Maturing, 441 Mean ordinate method, 35, 102

-- width ratio, 301

Measurement units, 135 Mechanical efficiency, 32.3 Medullary rays, 444 Mensuration rules, 34-44 Metacentre, longitudinal , 89, 91 --, transverse, 66, 68-8 j

Mineral grease, 435 Mixing length, 196 Model basins (.fee Experimental tanks) Modulus factor, Table 50, 394 Moisture content, 442. Moment against tipping, 426 - - of inertia, 49, 139, 476, Fig. IJ 5 -- to change trim, 90, 91, 103 Momentum, t38(.) Monel metal, 460 Moorsom system, 465 Morrish fomluia for V.C.B., 105 Motion in a seaway, 356-387 Motor launches, 229, 327 -- sailer, 260, 471 Moulded dimensions, 23 Movable weights, 92 Multi-hulled vessels, 26. Munion (division hetween stem lights) , 15

Nautical mile, IJ6(C), 137(b) Normand formula for M.C.T.I"', 91 Notation, dimensional, 135 --, general, 15 --, Propellers, 278

"0", Froude friction constant, 238

Oak, 443, 449 Obeche, 449 Ocean waves, 174-84 Offsets, 1,3 Optimum efficiency (form), 221(d) Ordinate stations, 24 Oregon pine, 441, 449 Outside multipliers (mensuration), 34

®, 169(b) 215 Paddle wheels, 268, :170-4 Paints, 1,°4, 462 Panama Canal rules, 468 Parabolas, J6-4' Parallel middle body, 24, 224

\03

SUBJECT INDEX AND GLOSSARY

"Park Avenue" boom, 2.57 Perfect fluid, 56, 144, 154 Permeability, II<5(m) -- formula, 12.2.

Peroba, 450 Perpendiculars, 24 Phantom ship, 287

Phosphor bronze, 460 Pitching forces, 360 -- periods, 317 Pitch-pine, 408, 450 Pitot tube, '49 Planimeter, 45 Planing coefficients, .139 -- forms, 336 Plastic hulls, 451 Plying limits, 12.0

Plywood, 444 Polar Moment of inertia, Fig. 135,476 Polyester resin, 451 Pomiglion (a knoh on the end of a gun), 15 Poaping, 215

Popoffka, 17

Porpoising, 338, 346 Position head, 140

Poundal, 136 Power (definition), t39(j) -- to carry sail , 2.61

Powering curves, 327, Fig. 104, Figs. t37--<),49O-'

-- methods, 320, 328 Pressure, absolute, 57 -- gradient, 65 -- head, 56-65 -- on inclined plane, 61 ---- plate, 156 -- wvolume relation, 6) Pressure waves, 173 Prismatic coefficient, 24, 173,216 Pro-metacentre, 69 Propeller area and number of blades, 30r --, constants, 28o, Table )0, 281 ,

Tables 61-5,484 -- design, 277, )11 -- drag, 384 --- ducted, :199 -- frequency, 42) -- handing, :178, 3 I2

50 4

- - inertia, Fig. 135,476 -- materials, )13, 460 -- pitch, 268, :179 -- strength, )1)

-- stresses, 478 - - super~cavitating, )08

-- theories, 277 Propulsive efficiency, )2)

Quarter wheels, 274 Quasi-propulsive efficiency, )la, 32)

Radial integration, 52 Radians, t 3 7( c) Rake, 25 Rayleigh's formula (eddy resistance), 161

Reaching, '59 Real fluids, J 44, 154 -- slip, 268 Redwood, 441,450 Reech method fur st"dbilicy, 83 Relation coefficient, 25 Relative rotative efficiency, 288 -- wind, 244 Residual resistence, 170212-231

---- of destroyer cypes, 229 ---- - hard chine hulls, )40 ---- - motor launches, 229 -- --, standard series, 217

Resistance constants, 169 -- of blunt-ended finings, 161

--, gravity type, 163 --, sailing vessels, 259 --, viscous, 16)

Restricted waterways, 146 Reynolds' experiments, 189 Reynolds number, 164, 2.42., -- --- for propeller, 172 -- stresses, 194, 208 Rhine lighters, JJO Righting moment, 67 Ripples, t73 Rivet hole deduction, 401, 405 Rock elm, 447 Rockered keel, 2.5 Rolling periods, 356 -- forces, 360

SUBJECT INDEX AND GLOSSARY

Rotor ship, 147 Rough surfaces, .20)

Round of beam corrcction, I I 3 Round-up, .2 ~

Rudders, 364-374 Run, 25

® (skin constant), 169«) Sail area, 256, 261 -- propulsion, l.49 Salinity, 17 Sapwood, 441. Scale effect, 168, 240 Scaling-up tank results, 235 Scantling numerals, )88 Schlick constant, 410

Scotchman (an anti-chafe hatten), 11' Seasoning timber, 441. Seaworthiness, 17, )80

Second moment, 139 Shallow water resistance, 331 -- - - waves, 186, 331 Shear stresses, 390, 40) Sheer, :15, J n -- correction, 112

-- deflection, 393 -- ratio, J 16 Ship terms, 15 Shut bevel, 25 Similarity (see Comparison Law) Simpson's First rule, 37, 102

- - Second rule, 38 Singing propellers, JII Sink and source, J ')0

Sinkage in fresh water, 62 __ _ _ restricted waterways, 146

Slacknl."Ss, Fig. 88, 157 Slip, Fig. 91, 268 Slugs, 136 Sluice keel, 21

Smith correction, 403 , 406 Snail, Fig. 80, 234 Soft woods, 441 Space (unit), 136(C) Specific gravity, 19,62, 138(h) Speed (defini tion), t37(a) --/Iength ratio, 161, 170(6)

-- of sound in water, 173 Spinnakers, 256 Spring vessels (see und" Oak), 449 --wood, 441 Spruce, 450 Squat, l.I 5, 336 Stabilisers, 37;, Stability at large angles, 72

---- small angles, Fig. 21,66 --, Bames' method, 75 --, Benjamin's method, 83 --, Blom's method, Fig. 33, 84 - - criterion, 381 -- cross curves, 8 t --, direct wedge method, 84 --, docking, 93 --- , dynamical , 68, 84 - - , flooded, U7-p· --, Leland's method, 8) --, longitudinal, 86-95 -- of submarines, 94 --, Reech's method, 83 -- requiremen IS, I J 2

--, transverse, 66-9~ Stagnation poin t, Fig. 60, J 5' 8 -- pressure, T able 27, 1;8, 243 Starting declivity, 433 Static friction, 435' -- pull, 292, Tables 32, J3 Steels, 453 Steering, 364 -- by propellers, 372 Stepped forms, 344 Stern types, 227

- - wheels, 274 "Storms" in towing tanks, 239 Stream tube, Fig. 50, 143

Streamline (definition) , 13 $

Streamlining, 18, 248 Strength of ships, 388- 408 Stresses in a seaway, 402 Subdivision factor, II7

- - rules, I 13-:18 Submarines, stability, 94 Summer freeboard, 110

Supersonic velocity, 173 Superstructures, corrections f Of, 112

50 1

SUBJECT INDEX AND GLOSSARY

Surface friction, 187-.210

-- tension, 17' --, wetted, 107, 337 Surging, 356 Suspended weights, 92 Symbols and notation, 15 Synchronous rolling and pitching, )61.

Tactical diameter, Fig. 116, 36S Tallene,431 Taylar's methodical series, Tables U-l,

216 Tchebycheff's rules, Table 2., 36, 4[ Teak, 408, 444, 45 I Temperature stress, 404 Thames tonnage, 16 "Three .. ten-one" lUIe (moments), 53 Thrust deduction factor, 287 -- horse-power, 288 -- load and pressure, .192

Timber conversion, 443 --, qualities of, 444 -- structure and growth, 440 Time (unit), '35(A) Timenoguy (prcn. "timrninoggie" -a rope

secured to the anchor to keep the jih sheets from fouling the flu1es), '5

Tip speed, 307 Tipping moment, 427 T obin bronze, 460 T oonage openings, J 15, 467 -- regulations, 465 Tons per inch, 26, 63, 101 Torque, 139(k) Torsional periods, 424 Toxic layer, 207 Transfer, Fig. 116, 36S Transitional flow, 192 Transmission efficiency, 324 T rapezoidal rule, 34 Triggers, launching, 434 Trim and trimming moments, 87, 103 Trimarans, 263 Trochoidal theory, 174 Troost's propeller constants, 282, 2.92,

295, Tables 61-1, 484-8 True wind, 244

506

Tugs, 470 Tumblehome, 26 Tungum,460 Turbulence stimulation, 238 Turbulent flow, 189 Turning circle, 364 -- frame, 2.6 Tutin rudder, 373 Tyloses (see under Oak), 449

Underwater fittings (materials), 460 U.S.T.M.B. Series 62 tests (hard chine

hulls), 345

Velocity (definition), 137(6) --head,140 Ventnor hydroplane, 350 Venturi effect, 146 -- meter, 14S Versine curve, 226 Vertical prismatic coefficient, 26 Vibration, horiwntal frequency, 421 --, modes and nodes, 409 --, precautions against, 423 --, vertical frequency, 409-421 Viscosity, 1 ~4 --, kinematic, 155 -- of air, 155 -- resistance, 164 Voith-Schneider propeller, 373 Vortex theory, 147, JIS Vortices, J 40, 159 Vosper stabiliser, J78

Wake factor and percentage, 169 --gain, 288 -- values, Fig. 96, 29 I WaterHnes, 26 Waterplane coefficient, 26 Watertight decks, IJ2 Wave, capillary, 173 -- causation, 180 --, dapotic, 173 -- energy, 179 -- groups, 185

SUBJECT INDEX AND GLOSSARY

--lengths, 176, Fig. 67, 181

-- line curve, 1.1.6 -- of oscil1ation and periods, 174 -- of translation, 186

-- resistance, l.U

-- trochoidal, 174 "Waveleis" form, 2.2.8 Way end pressure, 428 Weather helm, '57 Weight estimates, 468 -- of oil, Table 5, 58 -- - water Table, 4, ~8 Welding, 403, 453, 463 Western Red Cedar, 446 Wetted surface, 18, 107-8 "Wind and Water", 444

Wind speed, 181 -- tunnels, IS7 Wood v. steel, 439 Work (definition), 139(i) Working stresses, 401. Wych elm, 447

Yacht design (motOr), 470 Yaw-heel and yawing, 378

Zero cir~le, 46 Zimmerman formula (wind), 181

Zinc protectors, 46 t