Aerodynamic Loading Effects on Mistuned IBR Resonant Response

Abstract

Experiments are performed to provide fundamental mistuned IBR resonant response data. Intentional mistuning for resonant response control and off-design operating conditions on resonant response are investigated. The technical approach is centered on experimentally quantifying the resonant response of mistuned IBRs in the Purdue Transonic Research Compressor which features a 1½ stage axial-flow geometry representative of that used in the front stages of advanced aircraft engine high-pressure compressor designs. Utilizing the baseline IBR, experiments are performed utilizing an Agilis NSMS to quantify the effect of steady loading on the resonant response of each blade. The baseline IBR is then intentionally mistuned based on predictions from a single degree-of-freedom mistuning model with aerodynamic damping. The intentional mistuning is accomplished by inserting radial holes into the tip of selected blades. Experiments are then performed to quantify the effect of steady loading on the 2 nd bending resonant response of three intentionally mistuned IBRs.