The renewed interest in high-speed propulsion has led to increased activity in the development of the supersonic combustion ramjet engine for hypersonic flight applications. In the hypersonic regime the scramjet engine's specific thrust exceeds that of other propulsion systems. This book, written by a leading researcher, describes the processes and characteristics of the scramjet engine in a unified manner, reviewing both the theoretical and experimental research. The focus is on the phenomena that dictate the thermo-aerodynamic processes encountered in the scramjet engine, including component analyses and flowpath considerations; fundamental theoretical topics related to internal flow with chemical reactions and non-equilibrium effects, high-temperature gas dynamics, and hypersonic effects are included. Cycle and component analyses are further described, followed by flowpath examination. Finally, the book reviews the current experimental and theoretical capabilities and describes ground testing facilities and computational fluid dynamics facilities developed to date for the study of time-accurate, high-temperature aerodynamics.
Author(s): Corin Segal
Series: Cambridge Aerospace Series
Publisher: CUP
Year: 2009
Language: English
Pages: 271
Half-Title......Page 3
Title......Page 5
Series Title......Page 4
Copyright......Page 6
Contents......Page 7
Preface......Page 13
List of Acronyms......Page 17
1.1 The Ramjet and the Supersonic Combustion Ramjet (Scramjet) Engine Cycle......Page 19
1.2 Historical Overview......Page 22
1.3 Summary......Page 30
REFERENCES......Page 32
2.1.1 Field Equations of Fluid Motion......Page 34
2.1.1.2 Momentum Conservation Equations......Page 35
2.1.2 Constitutive Equations......Page 36
2.1.2.3 The Shear-Stress Tensor......Page 37
2.2.1 One-Dimensional Steady Flow......Page 38
2.2.2 The Rankine–Hugoniot Relations......Page 40
2.2.3 Reservoir Conditions and Thermal Choking in Constant-Area Ducts......Page 41
2.3.1 Thermodynamic Relations and the Gibbs Function......Page 43
2.3.2 Chemical Equilibrium......Page 44
2.3.3 The Law of Mass Action and Reaction-Rate Constants......Page 46
2.3.4 Air Equilibrium Composition......Page 48
2.4. Nonequilibrium Considerations......Page 50
REFERENCES......Page 51
3.1 Introduction......Page 53
3.2 Real-Gas Equation of State......Page 54
3.3.1 Pressure, Energy, and the Equation of State......Page 55
3.3.2 Mean Free Path......Page 58
3.3.3 Maxwellian Distribution – Velocity Distribution Function......Page 60
3.3.4 Transport Coefficients......Page 62
3.4 Elements of Statistical Thermodynamics......Page 64
3.4.1.1 Modes of Energy......Page 65
3.4.1.2 Quantum Energy Levels and Degeneracies......Page 67
3.4.2 Counting the Number of Microstates for a Given Macrostate......Page 69
3.4.4 The Boltzmann Distribution......Page 71
3.4.5 Thermodynamic Properties in Terms of the Partition Function......Page 72
3.4.6 Evaluation of the Partition Function......Page 73
3.4.7 Evaluation of Thermodynamic Properties......Page 75
3.5 Hypersonic Flow......Page 77
REFERENCES......Page 79
4.1 Introduction......Page 80
4.2 Ideal Scramjet Cycle......Page 82
4.3 Trajectory and Loads......Page 86
4.4 Performance Analysis......Page 88
4.5 Combined Cycles......Page 90
4.5.1 The Turbine-Based Combined Cycle – TBCC......Page 91
4.5.2 The Rocket-Based Combined Cycle – RBCC......Page 93
4.5.2.1 RBCC Systems' Mode of Operation......Page 94
4.5.2.2 Combined-Cycle Propulsion Technical Issues......Page 96
4.5.2.3 Mode-Specific RBCC Technical Issues......Page 97
REFERENCES......Page 100
5.1.1 Introduction......Page 105
5.1.2.1 Pressure Recovery and Kinetic Energy Efficiency......Page 108
5.1.2.2 The Pressure Coefficient KWP......Page 111
5.1.2.3 Inlet Performance – Compression and Contraction Ratio Effects......Page 113
5.1.3.1 Inlet Starting......Page 116
5.1.3.2 Viscous Interactions......Page 118
5.1.3.3 Shock–Boundary-Layer Interactions......Page 121
5.1.4.1 Intake Air Energy Management......Page 124
5.1.4.2. Flow Deceleration Using a Magnetic Field......Page 125
5.1.4.3 Flow Control Using Fuel Injection......Page 132
5.1.5 Summary......Page 139
5.2 Nozzles......Page 140
REFERENCES......Page 142
6.1 Introduction......Page 145
6.2 Time Scales......Page 146
6.3 Fuel–Air Mixing......Page 148
6.3.1 Parallel, Unbounded, Compressible Flows......Page 149
6.3.1.1 The Definition of the Convective Mach Number......Page 151
6.3.1.2 Two-Dimensional Shear-Layer Growth – Velocity and Density Dependence......Page 153
6.3.1.3 Compressibility Effects on Shear-Layer Growth......Page 154
6.3.1.4 Effects of Heat Release on the Shear Layer......Page 155
6.3.1.5 Mixing Within the Shear Layer......Page 156
6.3.2 Mixing of Angled or Transverse Flows......Page 157
6.3.3 Degree of Mixing and Mixing Efficiency......Page 166
6.3.4 Mixing Enhancement......Page 169
6.4 Chemical Kinetics – Reaction Mechanisms......Page 175
6.4.1 Hydrogen–Air Reaction Mechanisms......Page 176
6.4.1.1 Reduced Mechanisms for Hydrogen–Air Combustion......Page 181
6.4.2 Reaction Mechanisms for Hydrocarbons......Page 183
6.4.3 Summary......Page 188
6.5 Flame Stability......Page 189
6.5.1 Recirculation-Region Flow Field......Page 190
6.5.2 Recirculation-Region Temperature......Page 192
6.5.3 Local Equivalence Ratio Analysis......Page 194
6.5.4 Recirculation-Region Composition Analysis......Page 195
6.5.5 Stability Parameter Formulations......Page 197
6.6 Combustion Chamber Design and Heat-Release Efficiency......Page 200
6.6.1 Isolator......Page 201
6.6.2.1 General Chamber Design Parameters......Page 205
6.6.2.2 Pressure Rise and Combustion Efficiency......Page 207
6.7 Scaling Factors......Page 216
6.8.1 Fuels as Vehicle and Engine Component Coolant Agents......Page 219
6.8.2 Thermal versus Catalytic Decomposition......Page 222
6.8.3 Fuel Management......Page 224
REFERENCES......Page 225
7.2 Hypersonic Flight Domain......Page 233
7.3.1 Combustion-Heated Wind Tunnels......Page 235
7.3.2 Electrically Heated Wind Tunnels......Page 237
7.3.3 Arc-Heated Facilities......Page 239
7.4.1 Shock Tunnels......Page 240
7.4.2 Free-Piston Shock Tubes......Page 242
7.4.3 Expansion Tubes......Page 243
REFERENCES......Page 245
8.1 Introduction......Page 247
8.2.1 Field and Constitutive Equations......Page 248
Binary and Multicomponent Diffusion Coefficients......Page 249
Viscosity......Page 250
Convective Transport......Page 251
8.3 Turbulent Reacting Flow – Length Scales......Page 252
8.4 Computational Approaches for Turbulent, Chemically Reacting Flows......Page 254
8.4.1 Direct Numerical Simulation......Page 255
8.4.2 Reynolds-Averaged Navier–Stokes Simulation......Page 256
8.4.3 Turbulence Models......Page 257
8.4.4 Large-Eddy Simulation (LES)......Page 258
8.5 Scramjet-Flow Computational Results......Page 259
8.5.1 Steady-State Nonreacting Flows......Page 260
8.5.2 Chemically Reacting Flows......Page 262
8.6 Summary......Page 266
REFERENCES......Page 267
Index......Page 269
