Nonlinear rotor aeroelastic analysis with stall and advanced wake dynamics

This paper studies an effective lag damping prediction method for a flexible flap-lag-torsional hingeless rotor model and correlation with the experimental data for a four-bladed rotor. The ONERA dynamic stall models of lift, drag, and pitching moment for each aerodynamic airfoil element and an advanced three-dimensional finite state wake model are used. The nonlinear equations of motion are represented in terms of state variables with 4 × 10 structural state variables. Eight aerodynamic elements for each rotor blade and at least eight wake harmonics are employed. The aerodynamic and wake state variables are 4 × 48 and 45, respectively. A numerical simulation technique is applied to determine the transient response of the hingeless rotor model and to predict the lag damping. Numerical investigations indicate that the present theoretical/numerical method improves the correlation of the theoretical and experimental results compared to an earlier eigenvalue, perturbation analysis.

Duke Scholars

Author Earl H. Dowell Thomas Lord Department of Mechanical Engineering and Materia ...