DAMPING PREDICTION FOR HINGELESS ROTOR AEROELASTIC STABILITY WITH EXPERIMENTAL CORRELATION

A numerical simulation technique is applied to determine the transient response of a hingeless rotor model and predict the lag damping for c orrelation with experimental results from a wind-tunnel test. Numerica l investigations indicate that the present theoretical/numerical metho d improves somewhat the correlation of the theoretical and experimenta l results over earlier eigenvalue, perturbation analyses. For a shaft angle of alpha(s) = 0 and -3 deg, the correlation still is not accepta ble for the advance ratios, mu > 0 2. In addition to a steady inflow m odel, a 3 x 3 dynamic inflow model is also used in the present method. The results with this dynamic inflow model show some improvement rela tive to the experimental data, as compared to the uniform inflow model . For further improvement of the correlation with the experimental dat a, a highly efficient, accurate aerodynamic model suitable for the rot or blade aeroelastic stability analysis is required.