EXPERIMENTAL INVESTIGATION OF OSCILLATING CASCADE AERODYNAMICS

A series of experiments are performed in the NASA Lewis Transonic Oscillating Cascade Facility to provide fundamental data quantifying the high subsonic and transonic steady and oscillating aerodyna mics of a biconvex airfoil cascade at realistic reduced frequency values for all interblade phase angles.This is accomplished by developing and utilizing an unsteady aerodynamic influence coefficient technique in which only one cascaded airfoil is oscillated at a time.The vector summation of the resulting airfoil surface unsteady pressures measured on a dynamically instrumented airfoil enables the unsteady aerodynamics of an equivalent cascade with all airfoils oscillating at any specified interblade phase angle to be determined.