Nonlinear Behavior of Pedestal Looseness Fault Rotor-Bearing System with Slowly Varying Mass

2010 ◽  
Vol 29-32 ◽  
pp. 2096-2101
Author(s):  
Yue Gang Luo ◽  
Song He Zhang ◽  
Bin Wu ◽  
Bang Chun Wen
Keyword(s):  
Fault Diagnosis ◽  
Dynamic Model ◽  
Chaotic Motion ◽  
Nonlinear Behavior ◽  
Speed Increase ◽  
Rotating Speed ◽  
Rotor Bearing ◽  
Set Up ◽  
Varying Mass ◽  
Bearing System

The dynamic model of the pedestal looseness fault rotor-bearing system with slowly varying mass was set up. The complex characteristics of the rotor-bearing system were numerically studied. Along with the increase of the looseness mass, the chaotic motion area and amplitude range increase in the region of critical rotating speed; and P-3 motion area disappears in the region of twice-critical rotating speed, chaos is the main motion form. Along with the increase of the coefficient of mass slowly varying amplitude, the instable rotating speed increase, and the chaotic motion area decreases, P-n motion area increases in the region of critical rotating speed and twice-critical rotating speed. The conclusions may provide basis reference for fault diagnosis.

Dynamic Behavior Analysis of Three-Span Rotor-Bearing System with Rub-Impact Fault

2012 ◽  
Vol 460 ◽  
pp. 160-164 ◽  
Author(s):  
Song He Zhang ◽  
Yue Gang Luo ◽  
Bin Wu ◽  
Bang Chun Wen
Keyword(s):  
Nonlinear Dynamics ◽  
Behavior Analysis ◽  
Dynamic Model ◽  
Dynamic Behavior ◽  
Rotor System ◽  
System Response ◽  
Rotor Bearing ◽  
Set Up ◽  
Bearing System ◽  
Main Influence

The dynamic model of the three-span rotor-bearing system with rub-impact fault was set up. The influence to nonlinear dynamics behaviors of the rotor-bearing system that induced by rub-impact of one disc, two discs and three discs were numerically studied. The main influence of the rotor system response by the rub-impact faults are in the supercritical rotate speed. There are mutations of amplitudes in the responses of second and third spans in supercritical rotate speed when rub-impact with one disc, and there are chaotic windows in the response of first span, and jumping changes in second and third spans when rub-impact with two or three discs.

Dynamic Characteristics of Nonlinear Elastics Rotor-Bearing System With Coupling Faults of Pedestal Looseness and Rub-Impact

2009 ◽  
Author(s):  
Yuegang Luo ◽  
Songhe Zhang ◽  
Zhaohui Ren ◽  
Bangchun Wen
Keyword(s):  
Dynamic Model ◽  
Dynamic Characteristics ◽  
Critical Speed ◽  
Dynamic Design ◽  
Coupling Faults ◽  
Nonlinear Motion ◽  
Speed Range ◽  
Rotor Bearing ◽  
Set Up ◽  
Bearing System

A dynamic model of the nonlinear elastics rotor-bearing system with coupling faults of pedestal looseness and rub-impact was set up, taking the linearity and cube item as the physics nonlinear factors. The complex characteristics of the rotor-bearing system were numerically studied. There exists complex nonlinear motion of periodic, quasi-periodic and chaotic in the response of the system. The main motions of the rotor-bearing system with rub-impact fault are periodic-2, periodic-4 and quasi-periodic within the super-critical speed range, but it with coupling faults of pedestal looseness and rub-impact are periodic-3 and chaotic. The influence of oil-film force to the rotor system is weakened by the pedestal looseness fault. The results may bring up theoretical references for fault diagnoses, dynamic design, and security running to rotor-bearing system.

Vibration model of rolling element bearings in a rotor-bearing system for fault diagnosis

2013 ◽  
Vol 332 (8) ◽  
pp. 2081-2097 ◽  
Author(s):  
Feiyun Cong ◽  
Jin Chen ◽  
Guangming Dong ◽  
Michael Pecht
Keyword(s):  
Fault Diagnosis ◽  
Rolling Element Bearings ◽  
Vibration Model ◽  
Rolling Element ◽  
Rotor Bearing ◽  
Bearing System

Numerical Simulation of a Bending-Torsion Coupling Gear Transmission System

2013 ◽  
Vol 448-453 ◽  
pp. 3403-3407
Author(s):  
Chao Feng Li ◽  
Shi Hua Zhou ◽  
Jie Liu
Keyword(s):  
Rotation Frequency ◽  
Variable Stiffness ◽  
Rolling Bearing ◽  
Rotational Frequency ◽  
Helical Gear ◽  
Angular Contact Ball Bearing ◽  
Rotating Speed ◽  
Response Characteristics ◽  
Rotor Bearing ◽  
Bearing System

Based on the establishment of angular contact ball bearing mechanical model, a nonlinear coupled lateral, torsional and axial dynamic model of helical gear-rotor-bearing system is established, and the dynamic differential equations of the coupled lateral-torsional-axial nonlinear vibration are deduced for imbalance rotors. The investigations are systematically carried out by oscillograms and spectrograms with rotating speed, taking into account eccentricity and nonlinear supporting by rolling bearing. The results show that the rotation frequency of the driven shaft appears in the driving shaft. In addition, the rotation frequencies and meshing frequency appear obviously in torsional direction. It can be seen that the lateral, torsional and axial response characteristics of driving and driven shafts obvious differences are due to the effects of the gear assembly characteristic, gear geometry parameters and the angular contact ball bearings characteristics. As a result, not only appear the rotational frequency and stiffness frequency, but also yield the bearing variable stiffness frequency and conbined frequency in lateral directions. However, the theory of the helical gear-rotor-bearing system still needs further research.

Motion of AMB Rotor in Backup Bearings

2002 ◽  
Vol 124 (3) ◽  
pp. 460-464 ◽  
Author(s):  
Sheng Zeng
Keyword(s):  
Chaotic Motion ◽  
Nonlinear Response ◽  
Linear Models ◽  
Rotating Speed ◽  
Harmonic Motion ◽  
Power Failure ◽  
Resonance Frequencies ◽  
Speed Range ◽  
Pass Through ◽  
Bearing System

This paper studies numerically the motion of an AMB rotor when it is supported only by backup bearings. Unlike a linear rotor-bearing system, which always undergoes a harmonic motion, the nonlinear AMB rotor-backup bearing system will undergo irregular or chaotic motion at some rotating speeds. The simulations show that in a wide rotating speed range there are several extra resonance frequencies, which are different from those appearing in well-known linear models. When a power failure occurs to AMB machinery, the AMB rotor should pass through all these resonance frequencies. Under some conditions, the full clearance whirl motion of the rotor in backup bearings will happen, which may lead to damage. In this paper several measures that could reduce the nonlinear response and hence avoid the full clearance motion are discussed.

scholarly journals Nonlinear Dynamic Analysis of Rotor Rub-Impact System

2019 ◽  
Vol 2019 ◽  
pp. 1-20
Author(s):  
Youfeng Zhu ◽  
Zibo Wang ◽  
Qiang Wang ◽  
Xinhua Liu ◽  
Hongyu Zang ◽  
...  
Keyword(s):  
Periodic Motion ◽  
Chaotic Motion ◽  
Nonlinear Dynamic Analysis ◽  
Period Doubling ◽  
Time History ◽  
Rotor System ◽  
Quasiperiodic Motion ◽  
Rotor Bearing ◽  
Motion Period ◽  
Bearing System

A dynamic model of a double-disk rub-impact rotor-bearing system with rubbing fault is established. The dynamic differential equation of the system is solved by combining the numerical integration method with MATLAB. And the influence of rotor speed, disc eccentricity, and stator stiffness on the response of the rotor-bearing system is analyzed. In the rotor system, the time history diagram, the axis locus diagram, the phase diagram, and the Poincaré section diagram in different rotational speeds are drawn. The characteristics of the periodic motion, quasiperiodic motion, and chaotic motion of the system in a given speed range are described in detail. The ways of the system entering and leaving chaos are revealed. The transformation and evolution process of the periodic motion, quasiperiodic motion, and chaotic motion are also analyzed. It shows that the rotor system enters chaos by the way of the period-doubling bifurcation. With the increase of the eccentricity, the quasi-periodicity evolution is chaotic. The quasiperiodic motion evolves into the periodic three motion phenomenon. And the increase of the stator stiffness will reduce the chaotic motion period.

Sign in / Sign up

Export Citation Format

Share Document