Recognition of torque load for elastic support rotor system based on axis orbit

Abstract

As the core component of rotating machinery, rotor system is often subjected to the different torque load in the operation process, resulting in the change of bearing load, system vibration and friction behavior between axis and bearing. Further, the operation situation of rotor system is changed. At present, the perfect conclusion has not been formed to identify torque load of rotor system. In this paper, a method was used to identify torque load of the elastic support and single-span rigid rotor system. The method utilized axis orbit as information source. Considering nonlinear oil film force, the mechanical model of single-span rigid rotor system was established and dynamics equation was deduced with torque load. The simulated orbit showed the shaft center offset downward and border amplitude increases with torque load. Based on two-dimensional image centroid, the both characteristic parameters were set up, the vertical offsets of axis orbit centroid and amplitude deviation. Torque situation of the rotor system would be identified by them. The single-span rotor test results showed the measured axis orbit was basically coincident with the simulated axis orbit. The calculate results of characteristic parameters were also consistent with the experimental results. That proved the effectiveness of this method to identify torque load through axis orbit.