STRUCTURAL AND AEROELASTIC ANALYSIS OF THE SR-7L PROPFAN.
This paper presents a structural and aeroelastic analysis of a large scale advanced turboprop rotor blade. This 8-blade rotor is designed to operate at Mach 0. 8 at an altitude of 35,000 ft. The blades are highly swept and twisted and of spar/shell construction. Due to the complexity of the blade geometry and its high performance, it is subjected to much higher loads and tends to be much less stable than conventional blades. Four specific analyses were conducted: steady deflection; natural frequencies and mode shapes; steady stresses; and aeroelastic stability. State-of-the-art methods were used to analyze the blades including a large deflection, finite element structural analysis, and an aeroelastic analysis including interblade aerodynamic coupling (cascade effects). The study found the blade to be structurally sound and aeroelastically stable.