Basics of Aerothermodynamics (Progress in Astronautics and Aeronautics Book 204)

The basics of aerothermodynamics are treated in this book with special regard to the fact that outer surfaces of hypersonic vehicles primarily are radiation cooled. The implications of this fact are different for different vehicle classes. In any case the properties of both attached viscous and separated flows are of importance in this regard. After a discussion of flight environment and transport phenomena in general, the most important aerothermodynamic phenomena are treated. Thermal surface effects are particularly considered, taking into account both radiation cooling and/or active cooling, for example of inner surfaces. Finally the simulation means of aerothermodynamics are discussed. Computational methods and their modelling problems as well as the problems of ground facility and flight simulation, including the hot experimental technique, are treated. 3540221328......Page 1 Table of Contents......Page 8 1.1 Classes of Hypersonic Vehicles and their Aerothermodynamic Peculiarities......Page 13 1.2 RV-Type and CAV-Type Flight Vehicles as Reference Vehicles......Page 17 1.3 The Objectives of Aerothermodynamics......Page 20 1.4 The Thermal State of the Surface and Radiation-Cooled Outer Surfaces as Focal Points......Page 21 1.5 Scope and Content of the Book......Page 24 References......Page 25 2.1 The Earth Atmosphere......Page 27 2.2 Atmospheric Properties and Models......Page 30 2.3 Flow Regimes......Page 33 2.4 Problems......Page 37 References......Page 38 3.1 Definitions......Page 40 3.2.1 Introduction and Local Analysis......Page 44 3.2.2 The Radiation-Adiabatic Surface and Reality......Page 50 3.2.3 Qualitative Behaviour of the Radiation-Adiabatic Temperature on Real Configurations......Page 53 3.2.4 Non-Convex Effects......Page 55 3.2.5 Scaling of the Radiation-Adiabatic Temperature......Page 59 3.2.6 Some Parametric Considerations of the Radiation-Adiabatic Temperature......Page 62 3.3.1 Configuration and Computation Cases......Page 65 3.3.2 Topology of the Computed Skin-Friction and Velocity Fields......Page 66 3.3.3 The Computed Radiation-Adiabatic Temperature Field......Page 69 3.4 Results of Analysis of the Thermal State of the Surface in View of Flight-Vehicle Design......Page 74 3.5 Problems......Page 75 References......Page 77 4 Transport of Momentum, Energy and Mass......Page 80 4.1 Transport Phenomena......Page 81 4.2.1 Introduction......Page 85 4.2.2 Viscosity......Page 86 4.2.3 Thermal Conductivity......Page 87 4.2.4 Mass Diffusivity......Page 89 4.2.5 Computation Models......Page 91 4.3.1 Transport of Momentum......Page 92 4.3.2 Transport of Energy......Page 98 4.3.3 Transport of Mass......Page 105 4.4 Remarks on Similarity Parameters......Page 109 References......Page 110 5 Real-Gas Aerothermodynamic Phenomena......Page 112 5.1 Van der Waals Effects......Page 113 5.2 High-Temperature Real-Gas Effects......Page 115 5.4 Thermal and Chemical Rate Processes......Page 119 5.5.1 Normal Shock Wave in Presence of Rate Effects......Page 124 5.5.2 Nozzle Flow in a "Hot" Ground-Simulation Facility......Page 127 5.6 Surface Catalytic Recombination......Page 132 5.7 A Few Remarks on Simulation Issues......Page 138 5.8 Computation Models......Page 139 5.9 Problems......Page 141 References......Page 142 6 Inviscid Aerothermodynamic Phenomena......Page 145 6.1 Hypersonic Flight Vehicles and Shock Waves......Page 146 6.2 One-Dimensional Shock-Free Flow......Page 151 6.3.1 Normal Shock Waves......Page 156 6.3.2 Oblique Shock Waves......Page 162 6.3.3 Treatment of Shock Waves in Computational Methods......Page 171 6.4.1 Bow-Shock Stand-Off Distance at a Blunt Body......Page 173 6.4.2 The Entropy Layer at a Blunt Body......Page 179 6.5 Supersonic Turning: Prandtl-Meyer Expansion and Isentropic Compression......Page 184 6.6 Change of Unit Reynolds Number Across Shock Waves......Page 188 6.7.1 Basics of Newton Flow......Page 191 6.7.2 Modification Schemes, Application Aspects......Page 194 6.8 Mach-Number Independence Principle of Oswatitsch......Page 198 6.9 Problems......Page 204 References......Page 206 7 Attached High-Speed Viscous Flow......Page 209 7.1.1 Attached Viscous Flow as Flow Phenomenon......Page 210 7.1.2 Some Properties of Three-Dimensional Attached Viscous Flow......Page 211 7.1.3 Boundary-Layer Equations......Page 212 7.1.4 Global Characteristic Properties of Attached Viscous Flow......Page 220 7.1.5 Wall Compatibility Conditions......Page 223 7.1.6 The Reference Temperature/Enthalpy Method for Compressible Boundary Layers......Page 227 7.1.7 Equations of Motion for Hypersonic Attached Viscous Flow......Page 229 7.2.1 Boundary-Layer Thicknesses and Integral Parameters......Page 233 7.2.2 Boundary-Layer Thickness at Stagnation Point and Attachment Lines......Page 246 7.2.3 Wall Shear Stress at Flat Surface Portions......Page 248 7.2.4 Wall Shear Stress at Attachment Lines......Page 252 7.2.5 Thermal State of Flat Surface Portions......Page 255 7.2.6 Thermal State of Stagnation Point and Attachment Lines......Page 258 7.3 Case Study: Wall Temperature and Skin Friction at the SÄNGER Forebody......Page 261 7.4 Problems......Page 267 References......Page 268 8 Laminar-Turbulent Transition and Turbulence in High-Speed Viscous Flow......Page 272 8.1 Laminar-Turbulent Transition as Hypersonic Flow Phenomenon......Page 275 8.1.1 Some Basic Observations......Page 276 8.1.2 Outline of Stability Theory......Page 279 8.1.3 Inviscid Stability Theory and the Point-of-Inflexion Criterion......Page 282 8.1.4 Influence of the Thermal State of the Surface and the Mach Number......Page 284 8.1.5 Real Flight-Vehicle Effects......Page 287 8.1.6 Environment Aspects......Page 300 8.2.1 Stability/Instability Theory and Methods......Page 303 8.2.2 Transition Models and Criteria......Page 305 8.2.4 Concluding Remarks......Page 309 8.3 Turbulence Modeling for High-Speed Flows......Page 310 References......Page 312 9 Strong Interaction Phenomena......Page 320 9.1 Flow Separation......Page 321 9.2 Shock/Boundary-Layer Interaction Phenomena......Page 327 9.2.1 Ramp-Type (Edney Type V and VI) Interaction......Page 328 9.2.2 Nose/Leading-Edge-type (Edney Type III and IV) Interaction......Page 337 9.3 Hypersonic Viscous Interaction......Page 341 9.4 Low-Density Effects......Page 353 References......Page 359 10.1 Some Notes on Flight Vehicle Design......Page 365 10.2 Computational Simulation......Page 372 10.3 Ground-Facility Simulation......Page 377 10.4 In-Flight Simulation......Page 381 References......Page 382 11 The RHPM-Flyer......Page 388 References......Page 390 12 Governing Equations for Flow in General Coordinates......Page 392 References......Page 395 13.1 Constants and Air Properties......Page 396 13.2 Dimensions and Conversions......Page 397 References......Page 399 14.1 Latin Letters......Page 400 14.2 Greek Letters......Page 402 14.3.2 Lower Indices......Page 404 14.5 Acronyms......Page 406 C......Page 407 H......Page 408 L......Page 409 R......Page 410 T......Page 411 Z......Page 412 C......Page 413 F......Page 414 L......Page 415 R......Page 416 T......Page 417 X......Page 418 Permissions......Page 419 Springer 3540221328 1 Table of Contents 8 1 Introduction 13 1.1 Classes of Hypersonic Vehicles and their Aerothermodynamic Peculiarities 13 1.2 RV-Type and CAV-Type Flight Vehicles as Reference Vehicles 17 1.3 The Objectives of Aerothermodynamics 20 1.4 The Thermal State of the Surface and Radiation-Cooled Outer Surfaces as Focal Points 21 1.5 Scope and Content of the Book 24 References 25 2 The Flight Environment 27 2.1 The Earth Atmosphere 27 2.2 Atmospheric Properties and Models 30 2.3 Flow Regimes 33 2.4 Problems 37 References 38 3 The Thermal State of the Surface 40 3.1 Definitions 40 3.2 The Radiation-Adiabatic Surface 44 3.2.1 Introduction and Local Analysis 44 3.2.2 The Radiation-Adiabatic Surface and Reality 50 3.2.3 Qualitative Behaviour of the Radiation-Adiabatic Temperature on Real Configurations 53 3.2.4 Non-Convex Effects 55 3.2.5 Scaling of the Radiation-Adiabatic Temperature 59 3.2.6 Some Parametric Considerations of the Radiation-Adiabatic Temperature 62 3.3 Case Study: Thermal State of the Surface of a Blunt Delta Wing 65 3.3.1 Configuration and Computation Cases 65 3.3.2 Topology of the Computed Skin-Friction and Velocity Fields 66 3.3.3 The Computed Radiation-Adiabatic Temperature Field 69 3.4 Results of Analysis of the Thermal State of the Surface in View of Flight-Vehicle Design 74 3.5 Problems 75 References 77 4 Transport of Momentum, Energy and Mass 80 4.1 Transport Phenomena 81 4.2 Transport Properties 85 4.2.1 Introduction 85 4.2.2 Viscosity 86 4.2.3 Thermal Conductivity 87 4.2.4 Mass Diffusivity 89 4.2.5 Computation Models 91 4.3 Equations of Motion, Initial Conditions, Boundary Conditions, and Similarity Parameters 92 4.3.1 Transport of Momentum 92 4.3.2 Transport of Energy 98 4.3.3 Transport of Mass 105 4.4 Remarks on Similarity Parameters 109 4.5 Problems 110 References 110 5 Real-Gas Aerothermodynamic Phenomena 112 5.1 Van der Waals Effects 113 5.2 High-Temperature Real-Gas Effects 115 5.3 Dissociation and Recombination 119 5.4 Thermal and Chemical Rate Processes 119 5.5 Rate Effects, Two Examples 124 5.5.1 Normal Shock Wave in Presence of Rate Effects 124 5.5.2 Nozzle Flow in a "Hot" Ground-Simulation Facility 127 5.6 Surface Catalytic Recombination 132 5.7 A Few Remarks on Simulation Issues 138 5.8 Computation Models 139 5.9 Problems 141 References 142 6 Inviscid Aerothermodynamic Phenomena 145 6.1 Hypersonic Flight Vehicles and Shock Waves 146 6.2 One-Dimensional Shock-Free Flow 151 6.3 Shock Waves 156 6.3.1 Normal Shock Waves 156 6.3.2 Oblique Shock Waves 162 6.3.3 Treatment of Shock Waves in Computational Methods 171 6.4 Blunt-Body Flow 173 6.4.1 Bow-Shock Stand-Off Distance at a Blunt Body 173 6.4.2 The Entropy Layer at a Blunt Body 179 6.5 Supersonic Turning: Prandtl-Meyer Expansion and Isentropic Compression 184 6.6 Change of Unit Reynolds Number Across Shock Waves 188 6.7 Newton Flow 191 6.7.1 Basics of Newton Flow 191 6.7.2 Modification Schemes, Application Aspects 194 6.8 Mach-Number Independence Principle of Oswatitsch 198 6.9 Problems 204 References 206 7 Attached High-Speed Viscous Flow 209 7.1 Attached Viscous Flow 210 7.1.1 Attached Viscous Flow as Flow Phenomenon 210 7.1.2 Some Properties of Three-Dimensional Attached Viscous Flow 211 7.1.3 Boundary-Layer Equations 212 7.1.4 Global Characteristic Properties of Attached Viscous Flow 220 7.1.5 Wall Compatibility Conditions 223 7.1.6 The Reference Temperature/Enthalpy Method for Compressible Boundary Layers 227 7.1.7 Equations of Motion for Hypersonic Attached Viscous Flow 229 7.2 Basic Properties of Attached Viscous Flow 233 7.2.1 Boundary-Layer Thicknesses and Integral Parameters 233 7.2.2 Boundary-Layer Thickness at Stagnation Point and Attachment Lines 246 7.2.3 Wall Shear Stress at Flat Surface Portions 248 7.2.4 Wall Shear Stress at Attachment Lines 252 7.2.5 Thermal State of Flat Surface Portions 255 7.2.6 Thermal State of Stagnation Point and Attachment Lines 258 7.3 Case Study: Wall Temperature and Skin Friction at the SÄNGER Forebody 261 7.4 Problems 267 References 268 8 Laminar-Turbulent Transition and Turbulence in High-Speed Viscous Flow 272 8.1 Laminar-Turbulent Transition as Hypersonic Flow Phenomenon 275 8.1.1 Some Basic Observations 276 8.1.2 Outline of Stability Theory 279 8.1.3 Inviscid Stability Theory and the Point-of-Inflexion Criterion 282 8.1.4 Influence of the Thermal State of the Surface and the Mach Number 284 8.1.5 Real Flight-Vehicle Effects 287 8.1.6 Environment Aspects 300 8.2 Prediction of Stability/Instability and Transition in High-Speed Flows 303 8.2.1 Stability/Instability Theory and Methods 303 8.2.2 Transition Models and Criteria 305 8.2.3 Determination of Permissible Surface Properties 309 8.2.4 Concluding Remarks 309 8.3 Turbulence Modeling for High-Speed Flows 310 References 312 9 Strong Interaction Phenomena 320 9.1 Flow Separation 321 9.2 Shock/Boundary-Layer Interaction Phenomena 327 9.2.1 Ramp-Type (Edney Type V and VI) Interaction 328 9.2.2 Nose/Leading-Edge-type (Edney Type III and IV) Interaction 337 9.3 Hypersonic Viscous Interaction 341 9.4 Low-Density Effects 353 9.5 Problems 359 References 359 10 Simulation Means 365 10.1 Some Notes on Flight Vehicle Design 365 10.2 Computational Simulation 372 10.3 Ground-Facility Simulation 377 10.4 In-Flight Simulation 381 References 382 11 The RHPM-Flyer 388 References 390 12 Governing Equations for Flow in General Coordinates 392 References 395 13 Constants, Functions, Dimensions and Conversions 396 13.1 Constants and Air Properties 396 13.2 Dimensions and Conversions 397 References 399 14 Symbols 400 14.1 Latin Letters 400 14.2 Greek Letters 402 14.3 Indices 404 14.3.1 Upper Indices 404 14.3.2 Lower Indices 404 14.4 Other Symbols 406 14.5 Acronyms 406 Name Index 407 A 407 B 407 C 407 D 408 E 408 F 408 G 408 H 408 I 409 J 409 K 409 L 409 M 410 N 410 O 410 P 410 Q 410 R 410 S 411 T 411 V 412 W 412 Y 412 Z 412 Subject Index 413 A 413 B 413 C 413 D 414 E 414 F 414 G 415 H 415 I 415 K 415 L 415 M 416 N 416 P 416 R 416 S 417 T 417 U 418 V 418 X 418 Permissions 419 ISBN-13:,9783540221326 This book gives an introduction to the basics of aerothermodynamics, as applied in particular to winged re-entry vehicles and airbreathing cruise and acceleration vehicles. Beginning with a broad vehicle classification and a discussion of the flight environment, Basics of Aero-thermodynamics focuses on flight in the earth's atmosphere at speeds below approximately 8.0 km/s at altitudes below approximately 100.0 km. At such flight conditions the outer surfaces of hypersonic flight vehicles primarily are radiation cooled. This is taken into account by an introduction to the problem of the thermal state of the surface, and especially to the phenomena connected with surface radiation cooling. These are themes, which reappear throughout the remaining chapters. The implications of radiation cooling are different for the different vehicle classes. In any case the properties of both attached viscous and separating flows as well as thermo-chemical effects at and near the vehicle surface need to be considered. After a review of the issues of transport of momentum, energy and mass, real-gas effects as well as inviscid and viscous flow phenomena are treated. In view of their special importance for airbreathing hypersonic flight vehicles and for the discrete numerical methods of aerothermodynamics, considerable discussion is devoted to the issues of laminar-turbulent transition and turbulence, which follows a treatment of strong-interaction phenomena. Finally, simulation techniques for aerothermodynamics are considered, including computational methods and their modelling problems, as well as the problems of ground facility and in-flight simulation, including the hot experimental technique. The implications of Oswatitsch's Mach number independence principle are also treated. The book is for graduate students, doctoral students, design and development engineers, but also for technical managers. The reader should be familiar with the basics of fluid mechanics, aerodynamics, and thermodynamics The last two decades have brought two important developments for aeroth- modynamics. One is that airbreathing hypersonic flight became the topic of technology programmes and extended system studies. The other is the emergence and maturing of the discrete numerical methods of aerodyn- ics/aerothermodynamics complementary to the ground-simulation facilities, with the parallel enormous growth of computer power. Airbreathing hypersonic flight vehicles are, in contrast to aeroassisted re-entry vehicles, drag sensitive. They have, further, highly integrated lift and propulsion systems. This means that viscous eflFects, like boundary-layer development, laminar-turbulent transition, to a certain degree also strong interaction phenomena, are much more important for such vehicles than for re-entry vehicles. This holds also for the thermal state of the surface and thermal surface effects, concerning viscous and thermo-chemical phenomena (more important for re-entry vehicles) at and near the wall. The discrete numerical methods of aerodynamics/aerothermodynamics permit now - what was twenty years ago not imaginable - the simulation of high speed flows past real flight vehicle configurations with thermo-chemical and viscous effects, the description of the latter being still handicapped by in­ sufficient flow-physics models. The benefits of numerical simulation for flight vehicle design are enormous: much improved aerodynamic shape definition and optimization, provision of accurate and reliable aerodynamic data, and highly accurate determination of thermal and mechanical loads. Truly mul- disciplinary design and optimization methods regarding the layout of thermal protection systems, all kinds of aero-servoelasticity problems of the airframe, et cetera, begin now to emerge.