Understanding Hydraulics THIRD EDITION Les Hamill Senior Lecturer in Civil Engineering, School of Marine Science and Engineering, University of Plymouth palgrave macmillan
Preface to third edition Acknowledgements Principal notation Introduction viii x xiii xvi 1 Hydrostatics 1 1.1 Fundamentals 2 1.2 Hydrostatic pressure and force 5 1.3 Force on a plane (flat), vertical immersed surface 9 1.4 Location of the resultant force on a vertical surface 11 1.5 Force on a plane, inclined immersed surface 15 1.6 Force on a curved immersed surface 18 1.7 Variation of pressure with direction and buoyancy 22 1.8 The hydrostatic equation 28 1.9 Stratified fluids 28 Summary 32 2 Pressure measurement 35 2.1 Fundamentals 35 2.2 Piezometers 36 2.3 A simple U-tube manometer 38 2.4 A differential U-tube manometer 40 2.5 The inverted U-tube differential manometer 43 2.6 Adjusting the sensitivity of a manometer 48
iv 2.7 The Bourdon gauge 51 2.8 Surface tension 53 Summary 54 3 Stability of a floating body 57 3.1 Introduction 57 3.2 Factors affecting the stability of a floating body 60 3.3 Calculation of the metacentric height, GM 63 3.4 Period of roll 69 Summary 71 4 Fluids in motion 74 4.1 Introduction to the fundamentals 74 4.2 Classifying various types of fluid flow 79 4.3 Visualising fluid flow 83 4.4 The continuity equation 86 4.5 Understanding the momentum equation 88 4.6 Applying the momentum equation 93 4.7 The energy (or Bernoulli) equation 102 4.8 Applying the energy equation 109 4.9 Drag and lift 115 4.10 Free and forced vortices 117 Summary 120 5 Flow measurement 123 5.1 Introduction 123 5.2 The Venturi meter 124 5.3 The Pitottube. 130 5.4 Small and large orifices 132 5.5 Discharge over a sharp crested weir 142 5.6 Calibration of flow measuring devices 152 5.7 Velocity meters 157 Summary 159
pipeline time v 6 Flow through pipelines 163 6.1 Introduction 164 6.2 Understanding reservoir - flow 166 6.3 Parallel pipelines 175 6.4 Branching pipelines 178 6.5 The development of the pipe friction equations 183 6.6 Head losses at changes of section 201 Summary 206 7 Flow under a varying head - required to empty a reservoir 209 7.1 Introduction 210 7.2 Time to empty a reservoir of uniform cross-section 210 7.3 Time to empty a reservoir of varying cross-section 214 7.4 Flow between two tanks 221 Summary 223 8 Flow in open channels 225 8.1 Fundamentals 226 8.2 Discharge equations for uniform flow 231 8.3 Channel proportions for maximum discharge or velocity 237 8.4 Compound channels and the composite Manning's n 242 8.5 Environmentally acceptable channels 247 8.6 Specific energy and critical depth 247 8.7 Calculation of the critical flow conditions in any channel 257 8.8 Calculation of the critical flow in a trapezoidal channel 262 8.9 Calculation of the critical flow in a rectangular channel 264 8.10 Flow transitions 266 8.11 Gradually varying non-uniform flow 270 8.12 Surge waves in open channels 292 Summary 297 9 Hydraulic structures 300 9.1 Dams 300 9.2 Sluice gates and other control gates 314
vi 9.3 Flow around bridge piers and through bridge waterways 319 9.4 Culverts 331 9.5 Broad crested and Crump weirs 341 9.6 Throated flumes 345 Summary 349 10 Dimensional analysis and hydraulic models 352 10.1 Units and dimensions 353 10.2 Dimensional homogeneity 354 10.3 Dimensional analysis using the Rayleigh method 355 10.4 Dimensional analysis using the Buckingham n theorem 359 10.5 Hydraulic models and similarity 364 Summary 374 11 Turbines and pumps 377 11.1 Introduction 377 11.2 Impulse turbines 381 11.3 Reaction turbines 392 11.4 Performance equations and characteristics of turbines 395 11.5 Rotodynamic pumps 398 11.6 Pump performance equations, affinity laws and specific speed 400 11.7 Pump selection for a particular duty 406 11.8 Avoiding problems with cavitation and surge 413 11.9 Introduction to the analysis of unsteady pipe flow 418 11.10 The ram pump 428 Summary 431 12 Introduction to engineering hydrology 435 12.1 The hydrological cycle 436 12.2 Humankind's intervention in the hydrological cycle 439 12.3 Precipitation 445 12.4 Evaporation, transpiration and evapotranspiration 456 12.5 Infiltration and percolation 459
Derivation Solutions Graph vii 12.6 Surface runoff 464 Summary 475 13 Applications of engineering hydrology 477 13.1 Predicting a catchment's response to rainfall 478 13.2 The unit hydrograph rainfall-runoff model 482 13.3 Statistical analysis of riverflow data 492 13.4 Riverine and surface water flood risk management 507 13.5 Surface water sewer design using the modified rational method 519 13.6 Water supply reservoirs 527 13.7 Groundwater 532 Summary 547 14 Sustainable Drainage Systems (SUDS) 551 14.1 Introduction 552 14.2 What do SUDS do, and why? 554 14.3 Design of SUDS 558 14.4 Potential problems with SUDS 566 Summary 567 Bibliography and references 569 Appendix 1 - of equations 576 Appendix 2 - Appendix 3 - to self test questions 592 paper 617 Index 621