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| Preface | |
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| Introduction | |
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| Abbreviations | |
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| Background Material | |
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| Vibration of Single Degree of Freedom Systems | |
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| Setting up equations of motion for single DoF systems | |
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| Free vibration of single DoF systems | |
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| Forced vibration of single DoF systems | |
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| Harmonic forced vibration - frequency response functions | |
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| Transient/random forced vibration - time domain solution | |
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| Transient forced vibration - frequency domain solution | |
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| Random forced vibration - frequency domain solution | |
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| Examples | |
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| Vibration of Multiple Degree of Freedom Systems | |
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| Setting up equations of motion | |
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| Undamped free vibration | |
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| Damped free vibration | |
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| Transformation to modal coordinates | |
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| 'Free-free' systems | |
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| Harmonic forced vibration | |
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| Transient/random forced vibration - time domain solution | |
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| Transient forced vibration - frequency domain solution | |
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| Random forced vibration - frequency domain solution | |
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| Examples | |
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| Vibration of Continuous Systems - Assumed Shapes Approach | |
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| Rayleigh-Ritz 'assumed shapes' method | |
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| Generalized equations of motion - basic approach | |
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| Generalized equations of motion - matrix approach | |
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| Generating aircraft 'free-free' modes from 'branch' modes | |
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| Whole aircraft 'free-free' modes | |
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| Examples | |
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| Vibration of Continuous Systems - Discretization Approach | |
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| Introduction to the finite element (FE) approach | |
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| Formulation of the beam bending element | |
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| Assembly and solution for a structure with beam elements | |
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| Torsion element | |
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| Combined bending/torsion element | |
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| Comments on modelling | |
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| Examples | |
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| Introduction to Steady Aerodynamics | |
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| The standard atmosphere | |
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| Effect of air speed on aerodynamic characteristics | |
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| Flows and pressures around a symmetric aerofoil | |
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| Forces on an aerofoil | |
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| Variation of lift for an aerofoil at an angle of incidence | |
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| Pitching moment variation and the aerodynamic centre | |
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| Lift on a three-dimensional wing | |
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| Drag on a three-dimensional wing | |
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| Control surfaces | |
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| Supersonic aerodynamics - piston theory | |
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| Transonic flows | |
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| Examples | |
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| Introduction to Loads | |
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| Laws of motion | |
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| D'Alembert's principle - inertia forces and couples | |
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| Externally applied/reactive loads | |
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| Free body diagrams | |
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| Internal loads | |
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| Internal loads for continuous representation of a structure | |
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| Internal loads for discretized representation of a structure | |
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| Intercomponent loads | |
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| Obtaining stresses from internal loads - structural members with simple load paths | |
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| Examples | |
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| Introduction to Control | |
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| Open and closed loop systems | |
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| Laplace transforms | |
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| Modelling of open and closed loop systems using Laplace and frequency domains | |
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| Stability of systems | |
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| PID control | |
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| Examples | |
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| Introduction to Aeroelasticity and Loads | |
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| Static Aeroelasticity - Effect of Wing Flexibility on Lift Distribution and Divergence | |
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| Static aeroelastic behaviour of a two-dimensional rigid aerofoil with spring attachment | |
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| Static aeroelastic behaviour of a fixed root flexible wing | |
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| Effect of trim on static aeroelastic behaviour | |
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| Effect of wing sweep on static aeroelastic behaviour | |
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| Examples | |
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| Static Aeroelasticity - Effect of Wing Flexibility on Control Effectiveness | |
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| Rolling effectiveness of a flexible wing - the steady roll case | |
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| Rolling effectiveness of a flexible wing - the fixed wing root case | |
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| Effect of spanwise position of the control surface | |
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| Full aircraft model - control effectiveness | |
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| Effect of trim on reversal speed | |
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| Examples | |
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| Introduction to Unsteady Aerodynamics | |
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| Quasi-steady aerodynamics | |
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| Unsteady aerodynamics | |
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| Aerodynamic lift and moment for a harmonically oscillating aerofoil | |
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| Oscillatory aerodynamic derivatives | |
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| Aerodynamic damping and stiffness | |
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| Unsteady aerodynamics related to gusts | |
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| Examples | |
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| Dynamic Aeroelasticity - Flutter | |
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| Simplified unsteady aerodynamic model | |
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| Binary aeroelastic model | |
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| General form of the aeroelastic equations | |
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| Eigenvalue solution of flutter equations | |
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| Aeroelastic behaviour of the binary model | |
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| Aeroelastic behaviour of a flexible wing | |
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| Aeroelastic behaviour of a multiple mode system | |
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| Flutter speed prediction for binary systems | |
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| Flutter conic | |
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| Divergence of aeroelastic systems | |
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| Inclusion of unsteady reduced frequency effects | |
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| Control surface flutter | |
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| Whole aircraft model - inclusion of rigid body modes | |
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| Flutter in the transonic regime | |
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| Flutter in the supersonic regime - wing and panel flutter | |
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| Effect of nonlinearities - limit cycle oscillations | |
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| Examples | |
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| Aeroservoelasticity | |
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| Mathematical modelling of a simple aeroelastic system with a control surface | |
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| Inclusion of gust terms | |
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| Implementation of a control system | |
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| Determination of closed loop system stability | |
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| Gust response of the closed loop system | |
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| Inclusion of control law frequency dependency in stability calculations | |
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| Response determination via the frequency domain | |
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| State space modelling | |
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| Examples | |
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| Equilibrium Manoeuvres | |
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| Equilibrium manoeuvre - rigid aircraft under normal acceleration | |
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| Manoeuvre envelope | |
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| Equilibrium manoeuvre - rigid aircraft pitching | |
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| Equilibrium manoeuvre - flexible aircraft pitching | |
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| Flexible corrections to rigid aircraft pitching derivatives | |
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| Equilibrium manoeuvres - aircraft rolling and yawing | |
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| Representation of the flight control system (FCS) | |
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| Examples | |
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| Flight Mechanics Model for Dynamic Manoeuvres | |
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| Aircraft axes | |
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| Motion variables | |
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| Axes transformations | |
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| Velocity and acceleration components for moving axes | |
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| Flight mechanics equations of motion for a rigid aircraft | |
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| Representation of disturbing forces and moments | |
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| Equations for flexible aircraft in longitudinal motion | |
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| Solution of flight mechanics equations | |
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| Flight control system (FCS) | |
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| Dynamic Manoeuvres | |
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| Dynamic manoeuvre - rigid aircraft heave/pitch due to elevator input | |
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| Dynamic manoeuvre - flexible aircraft heave/pitch due to elevator input | |
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| General form of longitudinal equations | |
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| Dynamic manoeuvre - rigid aircraft roll due to aileron input | |
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| Dynamic manoeuvre - flexible aircraft roll due to aileron input | |
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| Flexible corrections to flight mechanics equations | |
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| Representation of the flight control system (FCS) | |
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| Examples | |
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| Gust and Turbulence Encounters | |
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| Gusts and turbulence | |
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| Gust response in the time domain | |
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| Time domain gust response - rigid aircraft in heave | |
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| Time domain gust response - rigid aircraft in heave/pitch | |
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| Time domain gust response - flexible aircraft | |
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| General form of equations in the time domain | |
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| Turbulence response in the frequency domain | |
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| Frequency domain turbulence response - rigid aircraft in heave | |
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| Frequency domain turbulence response - rigid aircraft in heave/pitch | |
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| Frequency domain turbulence response - flexible aircraft | |
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| General form of equations in the frequency domain | |
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| Representation of the flight control system (FCS) | |
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| Examples | |
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| Ground Manoeuvres | |
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| Landing gear | |
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| Taxi, take-off and landing roll | |
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| Landing | |
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| Braking | |
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| 'Spin-up' and 'spring-back' condition | |
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| Turning | |
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| Shimmy | |
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| Representation of the flight control system (FCS) | |
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| Examples | |
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| Aircraft Internal Loads | |
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| Limit and ultimate loads | |
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| Internal loads for an aircraft | |
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| General internal loads expressions - continuous wing | |
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| Effect of wing-mounted engines/landing gear | |
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| Internal loads - continuous flexible wing | |
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| General internal loads expressions - discretized wing | |
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| Internal loads - discretized fuselage | |
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| Internal loads - continuous turbulence encounter | |
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| Loads generation and sorting to yield critical cases | |
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| Aircraft dimensioning cases | |
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| Stresses from internal loads - complex load paths | |
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| Examples | |
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| Potential Flow Aerodynamics | |
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| Elements of inviscid, incompressible flow analysis | |
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| Inclusion of vorticity | |
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| Numerical steady aerodynamic modelling of thin two-dimensional aerofoils | |
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| Steady aerodynamic modelling of three-dimensional wings using a panel method | |
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| Unsteady aerodynamic modelling of wings undergoing harmonic motion | |
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| AICs in modal space | |
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| Examples | |
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| Coupling of Structural and Aerodynamic Computational Models | |
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| Mathematical modelling - static aeroelastic case | |
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| Two-dimensional coupled static aeroelastic model - pitch | |
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| Two-dimensional coupled static aeroelastic model - heave/pitch | |
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| Three-dimensional coupled static aeroelastic model | |
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| Mathematical modelling - dynamic aeroelastic response | |
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| Two-dimensional coupled dynamic aeroelastic model - bending and torsion | |
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| Three-dimensional flutter analysis | |
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| Inclusion of frequency-dependent aerodynamics for state space modelling - rational fraction approximation | |
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| Introduction to Industrial Practice | |
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| Aircraft Design and Certification | |
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| Aeroelastics and loads in the aircraft design process | |
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| Aircraft certification process | |
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| Aeroelasticity and Loads Models | |
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| Structural model | |
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| Aerodynamic model | |
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| Flight control system | |
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| Other model issues | |
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| Loads transformations | |
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| Static Aeroelasticity and Flutter | |
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| Static aeroelasticity | |
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| Flutter | |
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| Flight Manoeuvre and Gust/Turbulence Loads | |
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| Evaluation of internal loads | |
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| Equilibrium/balanced flight manoeuvres | |
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| Dynamic flight manoeuvres | |
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| Gusts and turbulence | |
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| Ground Manoeuvre Loads | |
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| Aircraft/landing gear models for ground manoeuvres | |
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| Landing gear/airframe interface | |
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| Ground manoeuvres - landing | |
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| Ground manoeuvres - ground handling | |
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| Loads processing | |
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| Testing Relevant to Aeroelasticity and Loads | |
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| Introduction | |
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| Wind tunnel tests | |
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| Ground vibration test | |
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| Structural coupling test | |
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| Flight simulator test | |
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| Structural tests | |
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| Flight flutter test | |
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| Flight loads validation | |
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| Appendices | |
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| Aircraft Rigid Body Modes | |
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| Rigid body translation modes | |
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| Rigid body rotation modes | |
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| Table of Longitudinal Aerodynamic Derivatives | |
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| Aircraft Symmetric Flexible Modes | |
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| Aircraft model | |
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| Symmetric free-free flexible mode | |
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| Model Condensation | |
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| Introduction | |
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| Static condensation | |
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| Dynamic condensation - Guyan reduction | |
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| Static condensation for aeroelastic models | |
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| Modal condensation | |
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| Modal reduction | |
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| Aerodynamic Derivatives in Body Fixed Axes | |
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| Longitudinal derivative Z[subscript w] | |
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| Lateral derivatives L[subscript p], L[subscript xi] | |
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| Aircraft Antisymmetric Flexible Modes | |
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| Aircraft model | |
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| Antisymmetric free-free flexible modes | |
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| References | |
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| Index | |
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| Programs Accessible (on the Companion Website) via the Internet | |
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| MATLAB/SIMULINK Programs for Vibration | |
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| Forced response of an SDoF system | |
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| Modal solution for an MDoF system | |
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| Finite element solution | |
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| MATLAB/SIMULINK Programs for Flutter | |
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| Dynamic aeroelastic calculations | |
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| Aeroservoelastic system | |
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| MATLAB/SIMULINK Programs for Flight/Ground Manoeuvres and Gust/Turbulence Encounters | |
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| Rigid aircraft data | |
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| Flexible aircraft data | |
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| Flight case data | |
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| Aerodynamic derivative calculation | |
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| Equilibrium manoeuvres | |
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| Dynamic manoeuvres | |
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| Gust response in the time domain | |
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| Gust response in the frequency domain | |
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| Ground manoeuvres | |