Dynamic Aero Elasticity and Flutter Problem — Lesson 2

This lesson covers the concept of dynamic aero elasticity, focusing on the flutter problem. It explains how this dynamic instability occurs in any elastic body in a flow, particularly wings, control surfaces, and vertical tides. The lesson discusses how lateral forces, such as lift on a vibrating twisting wing, can lead to oscillations and potentially violent structural breakage at certain speeds. It also delves into the linear aerodynamic theory used to analyze this phenomenon, highlighting the importance of perturbation stability analysis. The lesson further explores the concept of aerodynamic damping and its role in sustaining or dissipating energy in the system. The lesson concludes with a discussion on the methods to solve the flutter problem, including the Vg method.

Video Highlights

00:42 - Explanation of the flutter problem and its effects on wings and control surfaces.
04:20 - Explanation of the flutter condition and the importance of determining the flutter speed and flutter frequency.
25:54 - Discussion on the approach to solving the flutter problem using a 2 degree of freedom system.
60:28 - Explanation of the concept of panel flutter and its effects on aerofoil.
81:32 - Explanation of the effects of various parameters on flutter and methods to avoid it.

Key Takeaways

- Dynamic aero elasticity is a phenomenon that can lead to structural instability in elastic bodies in a flow, particularly wings and control surfaces.
- The flutter problem arises when lateral forces, such as lift, cause a wing to oscillate and potentially break at certain speeds.
- Aerodynamic damping plays a crucial role in either sustaining or dissipating energy in the system.
- The linear aerodynamic theory is used to analyze the flutter problem, with a focus on perturbation stability analysis.
- The Vg method is one of the techniques used to solve the flutter problem.