Papers Published

  1. Liu, L. and Dowell, E.H., The secondary bifurcation of an aeroelastic airfoil motion: effect of high harmonics, Nonlinear Dyn. (Netherlands), vol. 37 no. 1 (2004), pp. 31 - 49 [4d] .
    (last updated on 2007/04/10)

    Abstract:
    The nonlinear dynamical response of a two-degree-of-freedom aeroelastic airfoil motion with cubic restoring forces is investigated. A secondary bifurcation after the primary Hopf (flutter) bifurcation is detected for a cubic hard spring in the pitch degree-of-freedom. Furthermore, there is a hysteresis in the secondary bifurcation: starting from different initial conditions the motion may jump from one limit cycle to another at different fluid flow velocities. A high-order harmonic balance method is employed to investigate the possible bifurcation branches. Furthermore, a numerical time simulation procedure is used to confirm the stable and unstable bifurcation branches

    Keywords:
    aerodynamics;bifurcation;computational fluid dynamics;elastic hysteresis;flow simulation;harmonics;nonlinear dynamical systems;numerical analysis;springs (mechanical);