21st Congress of International Council of the Aeronautical Sciences, Melbourne, Australia, 13-18 September, 1998
Paper ICAS-98-1.7.2

A STUDY OF SELF INDUCED OSCILLATORY ROLLING MOTION: ANALYTICAL AND EXPERIMENTAL RESULTS

Guglieri G., Quagliotti F. B.
Turin Polytechnical University, Italy

Keywords: self induced, oscillatory. rolling motion

The paper deals with the study of an analytical model of wing rock, based on parameter identification of experimental data. The experiments were performed in the Aeronautical Laboratory of Politecnico di Torino, in the D3M Low Speed Wind Tunnel, on a 80° delta wing. Free to-roll tests have been used to determine build up and limit cycle characteristics of wing rock. Flow visualization techniques were also utilized in order to track vortex positions. The characteristics of limit cycle (oscillation amplitude and frequency) were compared in detail with reference results obtained in other laboratories. An analytical nonlinear model was derived. Parameters were identified by means of least squares approximation of experimental data with coherent initial conditions. The consistency of time histories, reproduced ,by numerical integration, was also analyzed. This formulation correctly predicts stable limit cycles for a wide range of airspeeds, angles of attack and release roll angles.

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