From Finite Element Multidisciplinary Analysis, Second Edition

14.1 Introduction

Modern aircraft and other aerospace vehicles have become increasingly complex because of the integration of distinct technologies used to attain numerous objectives in the areas of performance, control, flying qualities, maneuver techniques, fuel efficiency, and various mission requirements. The design process must respond to specifications from all disciplines to achieve these diverse goals and integrate accordingly. Design procedures must account for conflicting objectives and the interaction of aerodynamics, structures, and dynamics of control systems. Coupling between these dynamic elements of the model can be treated passively with structural modification and passive filtering or actively with control mechanisms driven by appropriate control laws. Analysis of the consequences of the design is essential to perform safe and effective mission tasks.

The term aeroelasticity [1] , [2] refers to the study of the phenomenon of mutual interaction of aerodynamic and structural dynamic forces and their effect on the design of an aerospace vehicle. In the absence of inertial forces this interaction is termed as static aeroelasticity. Instability of a vehicle occurs when elastic deformation induces additional aerodynamic forces that in turn produce further structural deformations. When continued, this process may cause eventual destruction of the vehicle. Flutter and divergence are examples of these phenomena, the latter occurring in the absence of inertial forces. Calculation of response for moving shock waves relates to dynamic aeroelasticity. The static aeroelastic phenomenon includes control effectiveness that relates to the influence of structural deformations on controllability of the vehicle. Also the phenomenon control surface reversal...

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Topics of Interest

15.1 Introduction In the previous chapter a fully integrated aeroelasticity and also aeroservo- elasticity analysis procedure was described for a complete aircraft configuration. This approach is...

Aeroelasticity is the term used to denote the field of study concerned with the interaction between the deformation of an elastic structure in an airstream and the resulting aerodynamic force. The...

2.5 Epilogue In this chapter we have considered the free-vibration analysis and modal representation for flexible structures, along with methods for solving initial-value and forced response problems...

Overview The pilot of the airplane ... succeeded in landing with roughly two-thirds of his horizontal tail surface out of action; some others have, unfortunately, not been so lucky.... The flutter...

Chapter List Chapter 28: Wing Problems Appendix A: Design of a Rear Fuselage Aircraft structures, being extremely flexible, are prone to distortion under load. When these loads are caused by...