Investigation on evolvement of dynamic behaviors of ship stern shaft-bearing system under the different rub-impact states based on attractor

Abstract

The ship stern shaft-bearing system is a typical nonlinear system, and its dynamic behavior is complex. In order to investigate the evolvement of dynamic behavior from the system, the attractor theory is introduced. Based on the calculated dynamic responses of the established dynamic model, the system's attractors were reconstructed, and the evolvement of dynamic behaviors under different rub-impact states was discussed. The results show that under the full annular rub-impact state, the attractor of the system is limit cycle attractor, and the volume of it increases gradually; under the partial rub-impact state, the attractor of the system goes through the process of breaking the tours attractor into a chaotic attractor and then converging into a tour attractor, and the volume of the attractor increases at first and then decreases; under the no rub-impact state, the attractor of the system is limit cycle attractor, and its volume decreases gradually. These characters of attractors demonstrate that under different rub-impact states, the system has experienced periodic motion, quasi-periodic, and chaotic motion. The attractors also reveal the evolutions of convergence and divergence.