PARAMETRIC STUDY OF THE UNBALANCE RESPONSE OF AN ECCENTRIC SQUEEZE FILM DAMPER-MOUNTED RIGID ROTOR

This paper presents a limited parametric study of the unbalanced respo nse of a rigid rotor supported by an eccentric squeeze film damper bea ring. The rotor unbalance response is approximated by a trigonometric series whose coefficients are determined by the collocation method. Th e results indicate that for small static misalignments and unbalances, nonsynchronous components are negligible and the rotor response is an offset ellipse. Nonsynchronous components increase as both the unbala nce and the static misalignment are increased. However, the amplitude of the rotor response is independent of the static misalignment direct ion. There is a tendency for the rotor to self-center in the vicinity of the resonance. This self-centering effect is more pronounced as the unbalance is increased and it is reduced as the static misalignment i s increased. For large unbalances and static misalignments, both main resonant jump and secondary resonant jump are predicted at speeds abov e twice the system critical speed.