DEFINITION:

Study of flexible structures situated in a flowing fluid. The origins are in the field of aerospace engineering (aeroplanes, helicopters rotors, turbomachineries, launchers and missiles), but aeroelasticity concerns also civil engineering (bridges, towers), mechanical and nuclear engineering. The first objective of aeroelasticity is to guarantee the integrity of the structure in the flow. Aeroelasticity is the study of the mechanics of coupled aerodynamics-structure systems: the structure is taken in the usual mechanical sense of the term, which is to say that it includes the passive structure and the structured coupled to control systems (flight controls, control law). In fact, the term aero-servo-elasticity is often used. High temperature environments can be important in aeroelastic problems, hence the terms aero-thermo-elasticity. So aeroelasticity incorporates the theory of continuum mechanics, fluid mechanics, and automatic systems. The scientific fields concerned, then, are steady and unsteady aerodynamics, the static and dynamic structure with its linear or non-linear properties, the servo controls, also with their linear and non-linear properties, and the coupling loop between the aerodynamics, the structure, and the systems. Aeroelastics problems can be static and
dynamic: In dynamic aeroelasticity, there is a further subdivision of problems into two broad types. The first type is when the flow is unsteady and the structure is in a steady position, but behaves dynamically. This is the case of problems having to do with atmospheric turbulence, boundary layer separation, and shock wave-boundary layer interaction. Buffeting also enters into this category of problems. The second type of general aeroelasticity problem has to do with those aeroelastic instabilities where the motion of the structure causes the forces, in that the aerodynamic forces do not exist without this motion. Flutter falls into this category and is
the most important topic of aeroelasticity.

(Source: ACARE Domain 206)

SUBDOMAINS:

1. Static aeroelasticity: Linear and non linear structure, Steady Aerodynamic, Static deformation, Static divergence, Aeroelastic optimisation.
2. Dynamic aeroelasticity: Structural dynamic (linear and non linear), Unsteady aerodynamic (linear and non linear), Fluid structure coupling, Fluid structure systems coupling, Flutter, Forced response.
3. Numerical aeroelasticity: Unsteady aerodynamic, Stability and response prediction, Aeroelastic optimisation, (multidisciplinary optimisation), Aeroelastic model updating, Aero-servo-elasticity.
4. Experimental aeroelasticity: Unsteady aerodynamic, Flutter model (design, manufacture, ground testing, wind tunnel testing).
5. Aeroelastic Certification: Ground vibration test, Flutter flight test.