Affiliations: Department of Aeronautical Engineering, Engineering
School of Sao Carlos, University of Sao Paulo, Av. Trabalhador Sancarlense,
400, 13561-020, Sao Carlos, SP, Brazil
Abstract: Stall-induced aeroelastic motion may present severe non-linear
behavior. Mathematical models for predicting such phenomena are still not
available for practical applications and they are not enough reliable to
capture physical effects. Experimental data can provide suitable information to
help the understanding of typical non-linear aeroelastic phenomena. Dynamic
systems techniques based on time series analysis can be adequately applied to
non-linear aeroelasticity. When experimental data are available, the methods of
state space reconstruction have been widely considered. This paper presents the
state space reconstruction approach for the characterization of the
stall-induced aeroelastic non-linear behavior. A wind tunnel scaled wing model
has been tested. The wing model is subjected to different airspeeds and dynamic
incidence angle variations. The method of delays is used to identify an
embedded attractor in the state space from experimentally acquired aeroelastic
response time series. To obtain an estimate of the time delay used in the state
space reconstruction from time series, the autocorrelation function analyis is
used. For the calculation of the embedding dimension the correlation integral
approach is considered. The reconstructed attractors can reveal typical
non-linear structures associated, for instance, to chaos or limit cycles.
Keywords: Aeroelasticity, state space reconstruction, stall-induced vibration, method of delays, non-linear dynamics
