PREDICTION OF POWER FLOWS THROUGH MACHINE VIBRATION ISOLATORS

A dynamic model is described for vibration isolation systems consisting of a source machine, multiple vibration isolators and a supporting structure. The machine is modeled as a rigid body of six degrees of freedom. Each of the isolators is treated as an assembly of six simple translational and rotational springs and allowed to be inclined at arbitrary angles. The supporting structure is composed of a rectangular plate and a number of reinforcing beams placed in any directions. The equation of motion of such a composite structure is derived from Hamilton's principle and then combined with that of the machine to determine the modal characteristics and vibrations of the whole isolation system, the reaction forces at each isolator, and the power flows into the supporting structure. Numerical examples are presented to examine the power flows under various situations.