Theoretical and Computational Aerodynamics
Aerospace Series (PEP)
1. Auflage November 2014
516 Seiten, Hardcover
Wiley & Sons Ltd
Aerodynamics has seen many developments due to the growth of scientific computing, which has caused the design cycle time of aerospace vehicles to be heavily reduced. Today computational aerodynamics appears in the preliminary step of a new design, relegating costly, time-consuming wind tunnel testing to the final stages of design.
Theoretical and Computational Aerodynamics is aimed to be a comprehensive textbook, covering classical aerodynamic theories and recent applications made possible by computational aerodynamics. It starts with a discussion on lift and drag from an overall dynamical approach, and after stating the governing Navier-Stokes equation, covers potential flows and panel method. Low aspect ratio and delta wings (including vortex breakdown) are also discussed in detail, and after introducing boundary layer theory, computational aerodynamics is covered for DNS and LES. Other topics covered are on flow transition to analyse NLF airfoils, bypass transition, streamwise and cross-flow instability over swept wings, viscous transonic flow over airfoils, low Reynolds number aerodynamics, high lift devices and flow control.
Key features:
* Blends classical theories of incompressible aerodynamics to panel methods
* Covers lifting surface theories and low aspect ratio wing and wing-body aerodynamics
* Presents computational aerodynamics from first principles for incompressible and compressible flows
* Covers unsteady and low Reynolds number aerodynamics
* Includes an up-to-date account of DNS of airfoil aerodynamics including flow transition for NLF airfoils
* Contains chapter problems and illustrative examples
* Accompanied by a website hosting problems and a solution manual
Theoretical and Computational Aerodynamics is an ideal textbook for undergraduate and graduate students, and is also aimed to be a useful resource book on aerodynamics for researchers and practitioners in the research labs and the industry.
Preface xvii
Acknowledgements xxi
1 Introduction to Aerodynamics and Atmosphere 1
1.1 Motivation and Scope of Aerodynamics 1
1.2 Conservation Principles 4
1.3 Origin of Aerodynamic Forces 6
1.4 Flow in Accelerating Control Volumes: Application of RTT 9
1.5 Atmosphere and Its Role in Aerodynamics 11
1.6 Static Stability of Atmosphere 17
Bibliography 20
2 Basic Equations of Motion 21
2.1 Introduction 21
2.2 Conservation Principles 23
2.3 Conservation of Linear Momentum: Integral Form 25
2.4 Conservation of Linear Momentum: Differential Form 26
2.5 Strain Rate of Fluid Element in Flows 28
2.6 Relation between Stress and Rate of Strain Tensors in Fluid Flow 32
2.7 Circulation and Rotationality in Flows 35
2.8 Irrotational Flows and Velocity Potential 36
2.9 Stream Function and Vector Potential 37
2.10 Governing Equation for Irrotational Flows 38
2.11 Kelvin's Theorem and Irrotationality 40
2.12 Bernoulli's Equation: Relation of Pressure and Velocity 41
2.13 Applications of Bernoulli's Equation: Air Speed Indicator 42
2.14 Viscous Effects and Boundary Layers 46
2.15 Thermodynamics and Reynolds Transport Theorem 47
2.16 Reynolds Transport Theorem 48
2.17 The Energy Equation 49
2.18 Energy Conservation Equation 52
2.19 Alternate Forms of Energy Equation 54
2.20 The Energy Equation in Conservation Form 55
2.21 Strong Conservation and Weak Conservation Forms 55
2.22 Second Law of Thermodynamics and Entropy 56
2.23 Propagation of Sound and Mach Number 60
2.24 One-Dimensional Steady Flow 61
2.25 Normal Shock Relation for Steady Flow 62
2.26 Rankine--Hugoniot Relation 64
2.27 Prandtl or Meyer Relation 65
2.28 Oblique ShockWaves 69
2.29 Weak Oblique Shock 71
2.30 Expansion of Supersonic Flows 74
Bibliography 76
3 Theoretical Aerodynamics of Potential Flows 77
3.1 Introduction 77
3.2 Preliminaries of Complex Analysis for 2D Irrotational Flows:
Cauchy--Riemann Relations 78
3.3 Elementary Singularities in Fluid Flows 81
3.4 Blasius' Theorem: Forces and Moment for Potential Flows 90
Mechanism 94
3.5 Method of Images 99
3.6 Conformal Mapping: Use of Cauchy--Riemann Relation 101
3.7 Lift Created by Jukowski Airfoil 111
3.8 Thin Airfoil Theory 116
3.9 General Thin Airfoil Theory 129
3.10 Theodorsen Condition for General Thin Airfoil Theory 134
Bibliography 135
4 FiniteWing Theory 137
4.1 Introduction 137
4.2 Fundamental Laws of Vortex Motion 137
4.3 Helmholtz's Theorems of Vortex Motion 138
4.4 The Bound Vortex Element 140
4.5 Starting Vortex Element 140
4.6 Trailing Vortex Element 141
4.7 Horse Shoe Vortex 142
4.8 The Biot-Savart Law 142
4.9 Theory for a Finite Wing 146
4.10 Consequence of Downwash: Induced Drag 147
4.11 Simple Symmetric Loading: Elliptic Distribution 149
4.12 General Loading on a Wing 154
4.13 Asymmetric Loading: Rolling and Yawing Moment 157
4.14 Simplified Horse Shoe Vortex 161
4.15 Applications of Simplified Horse Shoe Vortex System 162
4.16 Prandtl's Lifting Line Equation or the Monoplane Equation 167
Bibliography 169
5 Panel Methods 171
5.1 Introduction 171
5.2 Line Source Distribution 172
5.3 Panel Method due to Hess and Smith 176
5.4 Some Typical Results 183
Bibliography 188
6 Lifting Surface, Slender Wing and Low Aspect RatioWing Theories 189
6.1 Introduction 189
6.2 Green's Theorems and Their Applications to Potential Flows 190
6.3 Irrotational External Flow Field due to a Lifting Surface 192
6.4 Slender Wing Theory 201
6.5 Spanwise Loading 205
6.6 Lift on Delta or TriangularWing 206
6.7 Vortex Breakdown 214
6.8 Slender Body Theory 218
Bibliography 221
7 Boundary Layer Theory 223
7.1 Introduction 223
7.2 Regular and Singular Perturbation Problems in Fluid Flows 224
7.3 Boundary Layer Equations 225
7.4 Boundary Layer Thicknesses 230
7.5 Momentum Integral Equation 233
7.6 Validity of Boundary Layer Equation and Separation 235
7.7 Solution of Boundary Layer Equation 237
7.8 Similarity Analysis 238
7.9 Use of Boundary Layer Equation in Aerodynamics 252
Bibliography 258
8 Computational Aerodynamics 259
8.1 Introduction 259
8.2 A Model Dynamical Equation 260
8.3 Space--Time Resolution of Flows 263
Methods 265
8.4 An Improved Orthogonal Grid Generation Method for Aerofoil 275
8.5 Orthogonal Grid Generation 279
8.6 Orthogonal Grid Generation for an Aerofoil with Roughness Elements 284
8.7 Solution of Navier--Stokes Equation for Flow Past AG24 Aerofoil 287
Bibliography 291
9 Instability and Transition in Aerodynamics 295
9.1 Introduction 295
9.2 Temporal and Spatial Instability 298
9.3 Parallel Flow Approximation and Inviscid Instability Theorems 299
9.4 Viscous Instability of Parallel Flows 301
9.5 Instability Analysis from the Solution of the Orr--Sommerfeld Equation 304
9.6 Transition in Three-Dimensional Flows 318
9.7 Infinite Swept Wing Flow 320
9.8 Attachment Line Flow 321
9.9 Boundary Layer Equations in the Transformed Plane 322
9.10 Simplification of Boundary Layer Equations in the Transformed Plane 324
9.11 Instability of Three-Dimensional Flows 325
9.12 Linear Viscous Stability Theory for Three-Dimensional Flows 328
9.13 Experimental Evidence of Instability on Swept Wings 332
9.14 Infinite Swept Wing Boundary Layer 334
9.15 Stability of the Falkner--Skan--Cooke Profile 337
9.16 StationaryWaves over Swept Geometries 340
9.17 Empirical Transition Prediction Method for Three-Dimensional Flows 340
Bibliography 343
10 Drag Reduction: Analysis and Design of Airfoils 347
10.1 Introduction 347
10.2 Laminar Flow Airfoils 350
10.3 Pressure Recovery of Some Low Drag Airfoils 358
10.4 Flap Operation of Airfoils for NLF 361
10.5 Effects of Roughness and Fixing Transition 362
10.6 Effects of Vortex Generator or Boundary Layer Re-Energizer 364
10.7 Section Characteristics of Various Profiles 364
10.8 A High Speed NLF Aerofoil 365
10.9 Direct Simulation of Bypass Transitional Flow Past an Airfoil 369
Bibliography 378
11 Direct Numerical Simulation of 2D Transonic Flows around Airfoils 381
11.1 Introduction 381
11.2 Governing Equations and Boundary Conditions 382
11.3 Numerical Procedure 384
11.4 Some Typical Results 387
Bibliography 406
12 Low Reynolds Number Aerodynamics 409
12.1 Introduction 409
12.2 Micro-air Vehicle Aerodynamics 412
12.3 Governing Equations in Inertial and Noninertial Frames 413
12.4 Flow Past an AG24 Airfoil at Low Reynolds Numbers 425
Bibliography 442
13 High Lift Devices and Flow Control 445
13.1 Introduction 445
13.2 Passive Devices: Multi-Element Airfoils with Slats and Flaps 449
13.3 Flow Control by Plasma Actuation: High Lift Device and Drag Reduction 465
13.4 Governing Equations for Plasma 468
13.5 Governing Fluid Dynamic Equations 475
13.6 Results and Discussions 476
Bibliography 484
Index 487
