Dynamic analysis of the single rotor-bearing system considering the comprehensive stiffness and damping

Abstract

Abstract The rotor system supported by the cylindrical roller bearings is widely used in various fields, such as aviation, space and machinery due to its importance. In study of the analysis of the vibration characteristics of the rotor system, it is important to accurately calculate the stiffness and damping of the cylindrical roller bearings. Therefore, in this paper, the dynamic characteristics of the simple rotor-bearing system were analyzed based on the new dynamic model of the rotor system considering the comprehensive stiffness and damping model of the cylindrical roller bearing. In consideration of the radial clearance of the cylindrical roller bearing, the radial load acting on the cylindrical roller bearing is derived and based on this, the Hertz contact stiffness model of the cylindrical roller bearing is obtained. After obtaining the oil film stiffness model of the cylindrical roller bearing according to the EHL theory, the comprehensive stiffness of the cylindrical roller bearing was calculated by combining the Hertz contact stiffness and the oil film stiffness of the cylindrical roller bearing. After a comprehensive damping model of the cylindrical roller bearing considering the radial clearance was created, a dynamic model of the simple rotor-bearing system was created based on the comprehensive stiffness and damping model of the cylindrical roller bearing. The dynamic characteristics of the simple rotor-bearing system were analyzed using the MATLAB program. The amplitude of the simple rotor-bearing system considering the comprehensive stiffness and damping was reduced by 18.2% compared to the case where it was not considered. This shows that the structure of the cylindrical roller bearing has a restraining effect on the unbalanced response of the rotor system.