Aeroelastic Analysis of Very Flexible Aircraft using Nonlinear Modal Solutions

Student : Renato Medeiros

Sponsor : CNPq


Summary:

Very flexible aircraft usually experience large shape changes during the flight. Because of the unique dynamics at play, common linear modal techniques may not be applied with reasonable accuracy to predict the deflections. Also, the aerodynamics based on a fixed wing with small deflections may fail in providing the basis for the aeroelastic analysis. 
This research looks into ways of modeling the structural dynamics and the aerodynamics of aircraft experiencing large deflections. For the structural solution, the linear modal equations are extended to include higher order terms, while the aerodynamic solution is calculated using the method of segments, dealing with nonlinearities and effects of large displacements. These techniques are combined in order to produce time-domain simulations with accuracy comparable to high-fidelity solutions, but with significantly reduced costs.

uCRM 13.5 wing model deformed in flight, calculated with ROM techniques.