EXPERIMENTS AND ANALYSIS FOR COMPOSITE BLADES UNDER LARGE DEFLECTIONS .2. DYNAMIC BEHAVIOR

The dynamic behavior of structurally coupled composite blades is investigated in this paper analytically and experimentally, while the static behavior was described in Part 1 of this article. The model developed there is linearized around a given static position to investigate the small amplitude vibrations of composite blades. The influence coefficients method is used together with a simple iterative finite-difference solution procedure to obtain a standard eigenvalue problem. Several experiments using thin, flat composite cantilevered beams are also performed, and the data obtained compare well with the results from the analysis. The presence of static deflections is shown to have a significant influence on the torsion and fore-and-aft (lead-lag) modes and frequencies. © 1990 American Institute of Aeronautics and Astronautics, Inc., All rights reserved.