Supersonic Inlet-Torsional Cascade Flutter

Currently there is a dearth of fundamental dynamic aeroelastic cascade data with which to validate and/or indicate necessary refinements in mathematical models of such phenomena. This paper describes a unique supersonic inlet with a subsonic axial component, torsional flutter cascade experiment, wherein a computer controlled electromagnetic airfoil excitation system is used to simulate the fundamental time-dependent airfoil interaction, assure physical periodicity, and control the interblade phasing angle. Experimental data are presented which indicate the variation and significance of the cascade inlet Mach number, the stagger angle, and, in particular, the interblade phasing angle on the cascade dynamic torsional aeroelastic characteristics.