Dynamic response of a rub-impact rotor system under axial thrust

Abstract

A model of a rigid rotor system under axial thrust with rotor-to-stator is developed based on the classic impact theory and is analyzed by the Lagrangian dynamics. The rubbing condition is modeled using the elastic impact-contact idealization, which consists of normal and tangential forces at the rotor-to-stator contact point. Mass eccentricity and rotating speed are used as control parameters to simulate the response of rotor system. The motions of periodic, quasi-periodic and chaotic are found in the rotor system response. Mass eccentricity plays an important role in creating chaotic phenomena.

Vibration analysis of coupled bending-torsional rotor-bearing system for hydraulic generating set with rub-impact under electromagnetic excitation

“…However, whether the single bending oscillation or coupled bending-torsional vibration is chosen as the starting point of study, the basic objects of model establishment among the literatures described above were mainly focused on the high-speed, horizontal rotor structure and single rubbing fault [1][2][3][4][5][6][7][8][9][15][16][17][18][19][20][21][22][23], while the reports about low-speed, vertical systems such as hydraulic generating set were insufficient, and the nonlinear dynamic analyses of corresponding rub-impact rotor systems accompanied by other faults were more limited [10][11][12][13][14].…”

“…Furthermore, the research object has also been developed from single bending vibration [2][3][4][5][6][7][8][9][10][11][12][13][14][15] to coupled bending-torsional oscillation [16][17][18][19][20][21][22][23], gradually. Edwards et al [16] were treated as the first scholar introducing the torsional degree of freedom (DOF) into the vibration analysis of rotor system with rub-impact.…”

Research of Nonlinear Vibration of Aero-Engine in Windmilling Imbalance with Wing Degree-of-freedom

“…In the process of numerical simulation, a small contact penetrative area is included between the rotor and stator. Generally, the value of the contact stiffness is orders of magnitudes higher than the rotor or stator support stiffness in the contact penetrative area, then the order of magnitudes of the contact depth is much lower than one of the displacement of the rotor or stator [3].So the contact penetrative area of the rotor and stator can be simplified as a single point in mathematics [4]. The contact depth is defined as: …”

Dynamics of Unbalanced Flexible Rotor With Anisotropic Supports During Contact With the Stator

“…В свою очередь, безотрывное движение может представлять собой обкатку с прецессией в направлении, обратном на-правлению вращения -backward rolling, прямое синхронное или обратное скольжение ро-торов (forward slipping и backward slipping) [3,5,9]. Факторами, определяющими эти движения, являются [3,[9][10][11][12][13][14][15]: коэффициент трения скольжения, частота вращения, вели-чина зазора меду ротором и статором, эксцентриситет ротора, его массово-жесткостные характеристики, а также жесткость статора.…”

“…В рамках такой простой модели, дополненной условиями силового взаимодействия ротора со статором, выявлены основные закономерности динамики рото-ра в условиях задевания о статор [3,5,9,[13][14][15]16].…”