COMPARISON OF CALCULATED VIBRATORY ROTOR HUB LOADS WITH EXPERIMENTAL-DATA

Vibratory hub loads predicted by a comprehensive aeroelastic analysis are compared with wind tunnel test data. The analysis is based on a fi nite element method in space and time. Rotor loads are calculated usin g a force summation method, The test data include several model rotor configurations with different mass and stiffness distributions along t he blade. The influences of unsteady aerodynamics and nonuniform inflo w on variation of rotor loads prediction are investigated. Effects of blade inertial and stiffness properties on the rotor hub loads are als o investigated. The overall trends in vibratory hub loads due to chang es in mass and stiffness properties are satisfactorily captured by the analysis, However, the magnitudes of the prediction are generally low by as much as 50 percent in some cases.