Experimental Investigation of ABB Effect on Unbalanced Rotor Vibration

Rotor vibration due to unbalance causes a lot of problems during operation. Passive balancing devices represent one of the simplest ways to reduce rotor vibration. A (2 + n) degrees of freedom mathematical model is derived with respect to a Cartesian co-ordinate system for the unbalanced rotor with the automatic ball balancer. The model equations are expressed as state equations then solved numerically. Experimental rig is developed with a data acquisition system to enable measuring the rotor vibration amplitudes. A four balls automatic ball balancer (ABB) is designed, manufactured, and attached to the rotor. The numerical solutions of rotor vibration with and without the balancer are obtained and compared to the measured data to validate the mathematical model. The applied effect of the automatic ball balancer on vibration amplitudes is presented at different speed ranges.