Computational Modelling and Simulation of Aircraft and the Environment, Volume 2

Dominic J. Diston was a senior lecturer in aerospace engineering at the University of Liverpool and subsequently associate professor at the University of Nottingham. He also spent 25 years in the aerospace industry and has wide experience in dynamics, control and simulation of vehicles and systems. Major areas of work have included integrated flight/propulsion control, computer-aided engineering and fuel/thermal/power system simulation. All work has been closely linked with projects, most significantly Harrier, Typhoon, Nimrod and F-35.

• Preface xiAerospace Series Preface xiii1 A Simple Flight Model 11.1 Introduction 11.1.1 General Introduction to Volume 2 11.1.2 What Chapter 1 Includes 11.1.3 What Chapter 1 Excludes 21.1.4 Overall Aim 21.2 Flight Path 21.3 Flight Environment <20 km 51.4 Simple Propulsion Model 61.4.1 Reference Parameters 61.4.2 Simple Jet Engine Performance 71.4.3 ‘Better’ Jet Engine Performance 81.4.4 Simple Jet Engine Dynamics 101.5 Simple Aerodynamic Model 101.5.1 Idealised Aircraft 101.5.2 Idealised Wing 111.5.3 Wing/Tail Combination 131.5.4 Lift Distribution 151.5.5 Adding Flight Controls 181.6 Airspeed Definitions 201.7 Flight Model Architecture 212 Equations of Motion 252.1 Introduction 252.1.1 The Problem with Equations of Motion 252.1.2 What Chapter 2 Includes 252.1.3 What Chapter 2 Excludes 262.1.4 Overall Aim 262.2 Spatial Reference Model 262.2.1 Generic Reference Frames 262.2.2 Rotating Reference Frames 282.2.3 Elementary Rotations 292.2.4 Reference Frames for Position and Orientation 302.2.5 Reference Frame for Flight Path 322.2.6 Airspeed and Airstream Direction 332.3 Aircraft Dynamics 342.3.1 Mass Properties 342.3.2 Flight Parameters 352.3.3 Dynamic Equations of Motion 362.4 Aircraft Kinematics 392.4.1 Aircraft Position 392.4.2 Quaternions 402.4.3 Kinematic Equations of Motion 412.5 Initialisation 422.5.1 Balancing Forces 422.5.2 Typical Flight Conditions 442.5.3 Finding Aircraft Flight Parameters for Equilibrium 452.6 Linearisation 482.6.1 Linearisation of Dynamic Equations of Motion 482.6.2 Linearisation of Kinematic Equations of Motion 492.6.3 Linearisation of Aerodynamic Forces and Moments 502.6.4 Linearisation of Propulsive Forces and Moments 512.6.5 Linearisation of Gravitational Forces and Moments 512.6.6 The Complete Linearised System of Equations 523 Fixed-Wing Aerodynamics 553.1 Introduction 553.1.1 Fixed Wings and Aerodynamics 553.1.2 What Chapter 3 Includes 553.1.3 What Chapter 3 Excludes 563.1.4 Overall Aim 563.2 Aerodynamic Principles 563.2.1 Aerofoils 563.2.2 Dimensional Analysis 583.2.3 Lift, Drag, and Pitching Moment 593.2.4 Aerodynamic Centre 613.2.5 Wing Geometry 633.2.6 NACA Four-Digit Sections 643.3 Aerodynamic Model of an Isolated Wing 663.3.1 Aerodynamic Lift 663.3.2 Pitching Moment 683.3.3 Drag Force 693.3.4 Profile Drag 693.3.5 Induced Drag 703.3.6 Wave Drag 733.4 Trailing-Edge Controls 753.4.1 Incremental Lift 753.4.2 Incremental Drag 783.4.3 Incremental Pitching Moment 793.4.4 Hinge Moments 793.5 Factors affecting Lift Generation 813.5.1 Sideslip 813.5.2 Aircraft Rotation 823.5.3 Structural Flexibility 833.5.4 Ground Effect 853.5.5 Indicial Aerodynamics 853.6 Lift Distribution 863.7 Drag Distribution 894 Longitudinal Flight 914.1 Introduction 914.1.1 Flight with Wings Level 914.1.2 What Chapter 4 Includes 914.1.3 What Chapter 4 Excludes 914.1.4 Overall Aim 924.2 Aerodynamic Fundamentals 924.3 Geometry 924.4 Wing/Body Combination 944.4.1 Lift Force 944.4.2 Downwash 954.4.3 Pitching Moment 974.4.4 Aerodynamic Centre 994.4.5 Drag Force 994.5 All-Moving Tail 1014.5.1 Lift Force 1014.5.2 Pitching Moment 1024.5.3 Drag Force 1024.6 Flight Trim 1024.7 Flight Stability 1034.8 Trim Drag 1064.8.1 Minimum Drag 1064.8.2 Relative Speed and Relative Drag 1084.8.3 Variation of Minimum Drag Speed 1104.8.4 Minimising ‘Minimum’ Drag 1114.9 Steady-State Flight Performance 1134.9.1 Definitions 1134.9.2 Airspeeds for Maximum Endurance and Maximum Range 1134.9.3 Range and Endurance 1144.9.4 Alternative Form for Jet Aircraft Range and Endurance 1154.9.5 Fuel Required to Carry Fuel 1164.10 Dynamic Modes 1175 Gas Turbine Dynamics 1235.1 Introduction 1235.1.1 The Importance of Gas Turbines 1235.1.2 What Chapter 5 Includes 1235.1.3 What Chapter 5 Excludes 1235.1.4 Overall Aim 1245.2 Ideal Gas Properties 1245.2.1 Equation of State 1245.2.2 Energy, Enthalpy, and Entropy 1255.2.3 Specific Heat Capacity 1265.2.4 Adiabatic Gas Ratio 1265.2.5 Compressible Gas Properties 1275.2.6 Polytropic Processes 1275.3 Gas Dynamics 1285.3.1 Fundamental Relationships for Gas Flow 1285.3.2 Speed of Sound 1295.3.3 Bernoulli’s Equation 1305.3.4 Stagnation Conditions 1315.4 Engine Components 1325.4.1 Duct 1335.4.2 Junction 1345.4.3 Compressor 1345.4.4 Split Compressor 1365.4.5 Combustor 1365.4.6 Turbine 1375.4.7 Nozzle 1385.5 Engine Dynamics 1395.5.1 Shaft Speed Variation 1395.5.2 Massflow Variation 1395.5.3 Pressure Variation at Constant Temperature 1405.5.4 Pressure and Temperature Variation 1405.6 Engine Models 1415.6.1 Turbojet Engine 1415.6.1.1 Turbojet Specification 1425.6.1.2 Turbojet Initialisation 1445.6.1.3 Turbojet Physics 1455.6.1.4 Turbojet Dynamics 1465.6.2 Turbofan Engine 1475.7 Gas Properties Data 1505.7.1 Summary of Gas Properties 1515.7.2 Gas Mixtures defined by Mass Fractions 1515.7.3 Gas Mixtures defined by Mole Fractions 1525.7.4 Dry Air 1525.7.5 Fuel/Air Combustion Products 1536 Additional Topics 1576.1 Introduction 1576.1.1 Expanding the Scope of Volume 2 1576.1.2 What Chapter 6 Includes 1576.1.3 What Chapter 6 Excludes 1576.1.4 Overall Aim 1576.2 Structural Models 1586.2.1 Equations of Motion 1586.2.2 Coordinate Transformations 1596.2.3 Coupled Structure 1616.2.4 Wing-Fuselage Structure 1626.2.5 Whole Aircraft Structure 1696.3 Mass Distribution 1706.3.1 Mass Properties 1706.3.2 Transforming Mass Properties 1746.3.3 Combining Mass Properties 1756.3.4 Fuel Mass Distribution 175Bibliography 183Index 187