Dewan Tackling Turbulent Flows in Engineering

1. Auflage 2010
ISBN: 978-3-642-14767-8
Verlag: Springer
Format: PDF
Kopierschutz: Wasserzeichen (»Systemvoraussetzungen)

E-Book, Englisch, 124 Seiten

The emphasis of this book is on engineering aspects of fluid turbulence. The book explains for example how to tackle turbulence in industrial applications. It is useful to several disciplines, such as, mechanical, civil, chemical, aerospace engineers and also to professors, researchers, beginners, under graduates and post graduates. The following issues are emphasized in the book: - Modeling and computations of engineering flows: The author discusses in detail the quantities of interest for engineering turbulent flows and how to select an appropriate turbulence model; Also, a treatment of the selection of appropriate boundary conditions for the CFD simulations is given. - Modeling of turbulent convective heat transfer: This is encountered in several practical situations. It basically needs discussion on issues of treatment of walls and turbulent heat fluxes. - Modeling of buoyancy driven flows, for example, smoke issuing from chimney, pollutant discharge into water bodies, etc

Autoren/Hrsg.

Dewan, Anupam

Inhaltsverzeichnis

1;Tackling Turbulent Flowsin Engineering;2
1.1;Preface;4
1.2;Contents;7
1.3;1 Basics of Fluid Mechanics and Convective Heat Transfer;11
1.3.1;Abstract;11
1.3.2;1.1…Fluid Properties;11
1.3.2.1;1.1.1 Viscosity;11
1.3.2.2;1.1.2 Density;12
1.3.2.3;1.1.3 Thermal Conductivity;12
1.3.2.4;1.1.4 Surface Tension;13
1.3.2.5;1.1.5 Speed of Sound and Mach Number;13
1.3.2.6;1.1.6 Newtonian and Non-Newtonian Fluids;13
1.3.3;1.2…Treatments and Visualization of Fluid;14
1.3.3.1;1.2.1 Eulerian and Lagrangian Approaches;14
1.3.3.2;1.2.2 Streamline, Streakline and Pathline;14
1.3.3.3;1.2.3 Integral and Differential Treatments;15
1.3.4;1.3…Vorticity and Irrotational Flow;16
1.3.5;1.4…Force, Strain and Stress;17
1.3.6;1.5…Fluid Acceleration;19
1.3.7;1.6…Mass Conservation;19
1.3.8;1.7…Conservation of Linear Momentum;20
1.3.9;1.8…Navier--Stokes Equations;21
1.3.10;1.9…Conservation of Energy;21
1.3.11;1.10…Boundary Conditions;22
1.3.11.1;1.10.1 No Slip and No Temperature Jump Conditions;22
1.3.11.2;1.10.2 Inlet and Outlet;23
1.3.11.3;1.10.3 Interface;23
1.3.12;1.11…Convective Heat Transfer;23
1.3.13;1.12…Examples;25
1.3.13.1;1.12.1 Flow Normal to an Infinite Circular Cylinder;25
1.3.13.2;1.12.2 Thermal Boundary-Layer Inside a Heated Circular Tube;27
1.3.14;1.13…Concluding Remarks;28
1.3.15;References;28
1.4;2 Fluid Turbulence;29
1.4.1;Abstract;29
1.4.2;2.1…Physical Description;29
1.4.3;2.2…Stability of Laminar Flows;32
1.4.4;2.3…Transition and Onset of Turbulence;32
1.4.5;2.4…Types of Turbulent Flows;33
1.4.6;2.5…Significance of Turbulent Flows and Heat Transfer;34
1.4.7;2.6…Turbulence in the Vicinity of a Solid Wall;35
1.4.8;2.7…Task of a Turbulence Model;38
1.4.9;2.8…Concluding Remarks;39
1.4.10;References;39
1.5;3 Characteristics of Some Important Turbulent Flows;40
1.5.1;Abstract;40
1.5.2;3.1…Boundary-Layer Flow Past a Flat Plate;40
1.5.3;3.2…Forced and Free Convections;43
1.5.4;3.3…Simple Free Shear Flows;44
1.5.5;3.4…Circular Pipe and Parallel Plates;47
1.5.6;3.5…Separated Flows;49
1.5.7;3.6…Concluding Remarks;51
1.5.8;References;51
1.6;4 Reynolds-Averaged Governing Equations and Closure Problem;52
1.6.1;Abstract;52
1.6.2;4.1…Types of Reynolds-Averaging;52
1.6.2.1;4.1.1 Time-Average;53
1.6.2.2;4.1.2 Spatial-Average;53
1.6.2.3;4.1.3 Ensemble-Average;53
1.6.3;4.2…RANS and Scalar Equations;55
1.6.4;4.3…Closure Problem;56
1.6.5;4.4…Concluding Remarks;57
1.6.6;References;57
1.7;5 Models Based on Boussinesq Approximation;58
1.7.1;Abstract;58
1.7.2;5.1…Boussinesq Approximation;58
1.7.3;5.2…Models Based on Boussinesq Approximation;59
1.7.3.1;5.2.1 Mixing Length Models;59
1.7.3.2;5.2.2 One Equation Model;62
1.7.3.2.1;5.2.2.0 Based on Equation for Turbulence Kinetic Energy;62
1.7.3.2.2;5.2.2.0 Based on Equation for Eddy Viscosity;64
1.7.3.3;5.2.3 Two Equation Models;65
1.7.4;5.3…Limitations of Boussinesq Approximation;65
1.7.5;5.4…Examples;65
1.7.6;5.5…Concluding Remarks;65
1.7.7;References;66
1.8;6 k-- epsilon and Other Two Equations Models;67
1.8.1;Abstract;67
1.8.2;6.1…Introduction;67
1.8.3;6.2…Standard k-- epsilon Model;67
1.8.4;6.3…Exact Transport Equations for k and epsilon ;68
1.8.5;6.4…Modelled Transport Equations for k and epsilon ;68
1.8.6;6.5…Features of the k-- epsilon Model;70
1.8.7;6.6…Boundary Conditions;70
1.8.8;6.7…Treatment of Wall;71
1.8.8.1;6.7.1 Wall Functions Approach;71
1.8.8.1.1;6.7.1.1 Standard Wall Functions;71
1.8.8.1.2;6.7.1.2 Non-Equilibrium Wall Functions;72
1.8.8.1.3;6.7.1.3 Enhanced Wall Treatments;73
1.8.8.2;6.7.2 Low Reynolds Number Models;73
1.8.9;6.8…Example: Oscillatory Boundary Layers;75
1.8.10;6.9…Some Modern Variants of k-- epsilon Model;75
1.8.10.1;6.9.1 RNG k-- epsilon Model;76
1.8.10.2;6.9.2 Realizable k-- epsilon Model;76
1.8.10.3;6.9.3 k-- omega Model;77
1.8.11;6.10…V2f Model;78
1.8.12;6.11…Shear Stress Transport k-- omega Model;80
1.8.13;6.12…Other Two Equation Models;81
1.8.14;6.13…Modifications to k-- epsilon Model for Buoyancy Driven Flows;81
1.8.15;6.14…Other Modifications;84
1.8.16;6.15…Concluding Remarks;85
1.8.17;References;86
1.9;7 Reynolds-Stress and Scalar Flux Transport Model;88
1.9.1;Abstract;88
1.9.2;7.1…Introduction;88
1.9.3;7.2…Modeled Equations for Reynolds Stress Transport Model;88
1.9.3.1;7.2.1 Modeling of Turbulent Transport;89
1.9.3.2;7.2.2 Modeling of Pressure Strain;90
1.9.3.3;7.2.3 Modeling of Dissipation;90
1.9.4;7.3…Exact Transport Equation for Scalar Flux;91
1.9.5;7.4…Boundary Conditions;91
1.9.6;7.5…Treatment of Solid Walls;92
1.9.7;7.6…Features of Reynolds-Stress and Scalar Flux Transport Model;93
1.9.8;7.7…Algebraic Stress and Scalar Flux Models;93
1.9.9;7.8…Examples;94
1.9.10;7.9…Concluding Remarks;95
1.9.11;References;96
1.10;8 Direct Numerical Simulation and Large Eddy Simulation;97
1.10.1;Abstract;97
1.10.2;8.1…Introduction;97
1.10.3;8.2…Direct Numerical Simulation;98
1.10.4;8.3…Large Eddy Simulation;99
1.10.5;8.4…Subgrid Scale Models for LES;101
1.10.5.1;8.4.1 Smagorinsky SGS Model;101
1.10.5.2;8.4.2 Dynamic SGS Model;102
1.10.5.3;8.4.3 Scale Similarity SGS Model;103
1.10.6;8.5…DNS vis-à-vis LES;103
1.10.7;8.6…Detached Eddy Simulation and Hybrid Models;103
1.10.8;8.7…Treatment of Walls in LES;104
1.10.8.1;8.7.1 Wall Models That Use Equilibrium Laws;105
1.10.8.2;8.7.2 Velocity and Temperature TBLE Wall Model;106
1.10.9;8.8…Initial, Boundary Conditions and Duration of Computations;108
1.10.10;8.9…Concluding Remarks;109
1.10.11;References;110
1.11;9 Some Case Studies;111
1.11.1;Abstract;111
1.11.2;9.1…Heat Exchangers;111
1.11.3;9.2…Stirred Vessels;113
1.11.4;9.3…Flow in a Tundish Used in Steel Making;114
1.11.5;9.4…Turbulent Plume;115
1.11.6;9.5…LES and DES of Particle Deposition in a Human Throat;117
1.11.7;9.6…Unsteady Cross Ventilation in Buildings;118
1.11.8;9.7…Effect of Turbulent Prandtl Number on Film Cooling;119
1.11.9;9.8…Flow Over Rough Walls with Suction;120
1.11.10;9.9…Separated Convection Due to Backward Facing Step;120
1.11.11;9.10…Concluding Remarks;120
1.11.12;References;121
1.12;10 Conclusions and Recommendations;122
1.12.1;Abstract;122
1.12.2;10.1…Tackling Turbulence;122
1.12.3;10.2…CFD Issues;124
1.12.4;References;124
1.13;Index;125