CONTENTS PART I FLUID MOTIONS Chapter 1 INTRODUCTION The nature of fluids Pressure Viscosity Diffusion Viscosity as a diffusion coefficient 2 2 3 10 15 17 Chapter 2 FLOW PAST A SPHERE I: DIMENSIONAL; ANALYSIS, REYNOLDS NUMBERS, AND FROUDE NUMBERS 19 Introduction 19 Which variables are important? 20 Some dimensional reasoning, and its consequences 21 How to construct dimensionless variables 25 What if you choose the wrong variables? 25 “Dimensional analysis” 31 Significance of Reynolds numbers and Froude numbers 32 Conclusion 34 Chapter 3 FLOW PAST A SPHERE II: STOKES’ LAW, THE BERNOULLI EQUATION, TURBULENCE, BOUNDARY LAYERS, FLOW SEPARATION Introduction The Navier–Stokes equation Flow past a sphere at low Reynolds numbers Inviscid flow The Bernoulli equation Turbulence Boundary layers Flow separation Flow past a sphere at high Reynolds numbers Settling of spheres 35 35 35 36 40 43 48 58 65 70 74 Chapter 4 FLOW IN PIPES AND CHANNELS Introduction Laminar flow down an inclined plane Turbulent flow in pipes and channels: initial material Turbulent shear stress The turbulence closure problem Structure of turbulent boundary layers Flow resistance Velocity profiles Coherent structures in turbulent shear flow 83 83 84 91 93 98 99 103 115 149 Chapter 5 OPEN-CHANNEL FLOW Introduction Two practical problems Uniform flow Energy in open-channel flow 157 157 159 160 164 The hydraulic jump Hydraulic regimes of open-channel flow Gradually varied flow 172 176 178 Chapter 6 OSCILLATORY FLOW Introduction The nature of waves Water motions due to waves Wave boundary layers 190 Combined flow (waves plus current Chapter 7 FLOW IN ROTATING ENVIRONMENTS Introduction Playing on a rotating table The Coriolis effect on the Earth’s surface The Rossby number Inertia currents The Ekman spiral Geostrophic motion Ekman layers Planetary boundary layers 184 184 184 187 194 201 201 201 205 212 213 215 220 227 230 PART II SEDIMENT TRANSPORT Chapter 8 SEDIMENTS, VARIABLES, FLUMES Introduction Sediment Hydrodynamic perspective Particle motions vs. turbulence Observing sediment transport Variables Flumes 237 237 238 241 242 245 246 254 Chapter 9 THRESHOLD OF MOVEMENT Introduction Forces on bed particles Balance of forces Dimensional analysis How is the threshold for movement identified? Representations of the movement threshold Recasting the Shields diagram The Hjulstrøm diagram 260 260 260 265 267 269 272 275 278 Chapter 10 MOVEMENT OF SEDIMENT BY WATER FLOWS Introduction The bed, the flow, and the load Transport mode vs. flow intensity Bed load Suspension in a shear flow: the diffusional theory of suspension The effect of acceleration of gravity 285 285 286 289 294 307 314 Chapter 11 MOVEMENT OF SEDIMENT BY THE WIND 320 Introduction Saltation 320 321 Chapter 12 BED CONFIGURATIONS Introduction Unidirectional-flow bed configurations Oscillatory-flow and combined-flow bed configurations Wind ripples Eolian dunes 350 350 352 419 431 432 Chapter 13 THE SEDIMENT TRANSPORT RATE Introduction The sediment load and the sediment transport rate Predicting the sediment transport rate 450 445 445 445 Chapter 14 MIXED-SIZE SEDIMENTS Introduction A useful thought experiment The bed-surface size distribution Fractional transport rates Gradation independence versus equal mobility A thought experiment gradation independence versus equal mobility Real data on fractional transport rates, from the flume and from the field Movement threshold in mixed-size sediments Deviations from the condition of equal mobility More on sediment-discharge formulas 457 457 458 458 459 460 462 467 471 477 479 PART III CURRENT-GENERATED SEDIMENTARY STRUCTURES Chapter 15 DEPOSITION Introduction Modes of deposition Why deposition or erosion? A note on degradation 483 483 483 491 496 Chapter 16 CROSS STRATIFICATION Stratification and cross stratification The nature of cross stratification Some general points about interpretation The basic idea behind climbing-bed-form cross stratification Important kinds of climbing-bed-form cross stratification Cross stratification not produced by climbing bed forms 497 497 498 499 503 508 526 Chapter 17 PLANAR STRATIFICATION Introduction Features of planar lamination The origin of planar lamination in sands and sandstones Planar lamination in fine sediments 531 531 533 533 533 INDEX PARTIAL LIST OF SYMBOLS