23rd Congress of International Council of the Aeronautical Sciences, 8-13 September, 2002, Toronto, Canada
Paper ICAS 2002-4.2.2

LIMIT-CYCLE OSCILLATIONS OF AN AIRFOIL WITH PIECE-WISE LINEAR RESTORINGFORCES

B. H. K. Lee (1), L. Liu (1), Y. S. Wong (2)
(1) IAR/NRC, Canada; (2) University of Alberta, Canada

Keywords: nonlinear aeroelasticity, limit-cycle oscillations, piece-wise linear forces, numerical schemes, describing function, point transformation theory.

Nonlinear airfoil motion for incompressible airflow with a piece-wise linear restoring spring force is investigated. The possible dynamic responses are stable, divergent, limit-cycle oscillations and chaotic motions. Various methods of solving the aeroelastic response are discussed. The results from the point transformation method are used to assess the accuracy and limitations of the numerical schemes and the describing function technique.

view full paper