Experimental Modal Analysis Studies for Spinning Rotor-Shaft System

This work includes studies in modal testing of a spinning single-disc-rotor-shaft system supported on two ball bearings at the ends. Rotor systems, being non-self-adjoint in nature, require measurement of both a row and a column of the Frequency Response Function (FRF) matrix for the complete characterization of the system; this work attempts the same and discusses various issues and limitations in this regard. For this, the measured FRFs are analyzed to get the modal model. The forward and backward modes have been extracted from the measured FRFs and the extracted eigenvectors have also been plotted and analyzed.