ANALYTICAL FLUTTER INVESTIGATION OF A COMPOSITE PROPFAN MODEL

This paper presents a theoretical model and an associated computer program for predicting flutter of propfans in subsonic axial flow. The model is based on two-dimensional unsteady cascade strip theory and three-dimensional steady and unsteady lifting surface aerodynamic theory in conjunction with a finite element structural model for the blade. The analytical results compare well with published experimental data. Parametric studies are also presented, illustrating the effects on flutter speed of blade-steady aeroelastic deformations, blade setting angle, rotational speed, the number of blades, structural damping, and the number of modes.