Rotordynamic Design Analysis of a Squeeze Film Damper Test Ri

An analytical rotordynamic design study was conducted on a formerly operating squeeze film damper test rig comprising of an overhung rotor-bearing system; the sealed squeeze film damper test module is placed at the overhanging end. The test rig uses an eccentric rotating and hence whirling disk to provide variable parameters to test the performance of the Squeeze Film Damper. Essential parameters of the rotor-bearing system such as rotor critical speeds and sub-critical synchronous rotor response are calculated using simple Beam theory, Transfer Matrix Method (TMM) and Finite Element Method (FEM). Two approaches of FEM are used to calculate the synchronous response of rotors viz. Harmonic Response Method and Transient Time Integration Method. The critical speeds and synchronous response obtained from various methods match well. Analytical squeeze film damper relations are used to calculate approximate damping values of the damper test module. A residual unbalance response of the rotor system along with a static eccentricity provides higher rotor response and hence larger damping values than intended. A Finite Element Method study of the performance of the damped rotor-bearing system to approximate operation of the squeeze film damper test rig is provides reduced rotor orbits indicating incorrect operation of the test rig. The same is validated using previously acquired data from the test rig system.