Rotary Wing Structural Dynamics and Aeroelasticity

Preface to the Second Edition xv Preface to the First Edition xvii Introduction 1(4) Rotary Wing vs Fixed Wing 1(1) Methodology 2(3) Basic Analytical Techniques 5(62) Linear Single-Degree-of-Freedom System 5(9) Fourier Methods 14(5) Linear Two-Degree-of-Freedom System 19(16) Laplace Transform 35(2) Structural Damping 37(5) Matrices 42(10) Vector Calculus 52(8) Theorem of Coriolis 60(7) Rotating Beams 67(60) Basic Equations for Bending 67(12) Reference Uniform Blade 79(5) Numerical Methods 84(11) Approximate Methods 95(6) Two-Bladed Rotor 101(3) Blade Torsion Dynamics 104(8) Coupling Effects 112(15) Gyroscopics 127(22) Rotational Motion of a Solid Body 127(3) Simplified Gyroscope Equation 130(4) Precession and Nutation Characteristics 134(4) Gyroscopic Characteristics of Rotor Blades 138(11) Drive System Dynamics 149(40) Shaft Critical Speeds 149(13) Torsional Natural Frequencies of Shafting Systems 162(18) Special Devices 180(9) Fuselage Vibrations 189(50) Dynamic Loads 189(27) Harmonic Rotor Hub Loads 216(4) Nonrotor Sources of Fuselage Excitation 220(2) Rotor-Fuselage Interactions 222(17) Methods for Vibration Control 239(36) Basic Modification Methodology 239(5) Modification of Blade Dynamics 244(2) Modification of Fuselage Dynamics 246(5) Vibration-Suppression Devices 251(24) Vibration Test Procedures 275(22) Basic Shake Testing 275(17) Other Test Objectives 292(5) Stability Analysis Methods: Linear Systems 297(38) Basic Concepts 297(2) Basic Tools for Linear Systems: Constant Coefficients 299(10) Linear Multiple-Degree-of-Freedom Systems: Constant Coefficients 309(6) Linear Multiple-Degree-of-Freedom Systems: Periodic Coefficients (Floquet Theory) 315(10) Nyquist Criterion for Multiple-Degree-of-Freedom Systems 325(10) Mechanical and Aeromechanical Instabilities of Rotors 335(52) Unsymmetrical Rotor Instability 335(8) Quasi-Steady Aerodynamics 343(9) Rotor Weaving 352(10) Blade Pitch-Flap-Lag Instability 362(17) Rotordynamic Instabilities 379(8) Mechanical and Aeromechanical Instabilities of Rotor-Pylon Systems 387(60) Multiblade Coordinates and Rotor Modes 387(2) Rotor-Nacelle Whirl Flutter 389(15) Ground Resonance Instability 404(20) Air Resonance 424(9) Air Mass Dynamics 433(14) Unsteady Aerodynamics and Flutter of Rotors 447(82) Introduction and Classification 447(4) Two-Dimensional Frequency-Domain Theories 451(18) Two-Dimensional Arbitrary Motion Theories 469(16) Bending-Torsion Flutter 485(11) Three-Dimensional Aerodynamic Theories 496(12) Dynamic Stall and Stall Flutter 508(21) Analysis of Nonlinear Systems 529(28) Introduction 529(1) Simple Linearization 530(5) Transient Solutions Using Numerical Integration 535(11) Quasi-Linearization for Explicit Nonlinearities 546(2) Numerical Methods for Stability Estimation 548(5) Future Directions 553(4) Model Rotor Testing for Aeroelastic Stability 557(22) Introduction 557(1) Scaling Laws 557(5) Model Construction Considerations 562(2) Instrumentation and Test Procedures 564(10) Aeroelastic Considerations for Nonaeroelastic Testing 574(5) Elastomeric Devices for Rotorcraft 579(12) Introduction 579(1) Examples of Elastomeric Devices 579(2) Basic Characteristics of Elastomeric Materials 581(3) Elastomeric Lead-Lag Dampers 584(5) Other Applications of Elastomerics 589(2) Blade-Section Properties 591(34) Introduction 591(1) Generalized Blade Elastic Properties 591(3) Beams with Thin-Shell Closed-Cell Construction 594(11) Multicell Beams 605(11) Total Section Properties 616(4) Hygrothermal Effects in Composites 620(2) Prismatic Bars 622(3) Cross-over Topics 625(26) Interactions of the Rotor Drive and Engine/Fuel Control Systems 625(17) Aeroelastic Optimization 642(9) Concluding Thoughts 651(6) Key Historical Milestones 651(3) What's on the Horizon? 654(3) Appendix A Glossary of Rotorcraft-Related Terms 657(8) Appendix B Charts for Blade Frequency Estimation 665(12) Appendix C Generalized Frequency-Domain Substructure Synthesis 677(8) Appendix D Basic Equations of Motion for Ground Resonance and Air Resonance 685(22) Appendix E Composite Materials---Basics 707(12) References 719(10) Index 729(22) Supporting Materials 751