Nonlinear Dynamics of Marine Rotor-Bearing System Coupled With Vibration Isolation Structure Subject to Ship Rolling Motion

2021 ◽  
Author(s):  
Xuan Xie ◽  
Ming Li ◽  
Xiaolei Du
Keyword(s):  
Nonlinear Dynamics ◽  
Vibration Isolation ◽  
Rolling Motion ◽  
Rotor Bearing ◽  
Bearing System ◽  
Ship Rolling

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.

Nonlinear Dynamic Behavior of a Rotor Bearing System With Nonlinear Viscous Damping Suspension

2017 ◽  
Author(s):  
Shuai Yan ◽  
Bin Lin ◽  
Jixiong Fei ◽  
Pengfei Liu
Keyword(s):  
Dynamic Behavior ◽  
Nonlinear Dynamic ◽  
Vibration Isolation ◽  
Lubricating Oil ◽  
Viscous Damping ◽  
Oil Viscosity ◽  
Speed Range ◽  
Rotor Bearing ◽  
Nonlinear Dynamic Behavior ◽  
Bearing System

Nonlinear damping suspension has gained attention owing to its excellent vibration isolation performance. In this paper, a cubic nonlinear viscous damping suspension was introduced to a rotor bearing system for vibration isolation between the bearing and environment. The nonlinear dynamic response of the rotor bearing system was investigated thoroughly. First, the nonlinear oil film force was solved based short bearing approximation and half Sommerfeld boundary condition. Then the motion equations of the system was built considering the cubic nonlinear viscous damping. A computational method was used to solve the equations of motion, and the bifurcation diagrams were used to display the motions. The influences of rotor-bearing system parameters were discussed from the results of numerical calculation, including the eccentricity, mass, stiffness, damping and lubricating oil viscosity. The results showed that: (1) medium eccentricity shows a wider stable speed range; (2) rotor damping has little effect to the stability of the system; (3) lower mass ratio produces a stable response; (4) medium suspension/journal stiffness ratio contributes to a wider stable speed range; (5) a higher viscosity shows a wider stable speed range than lower viscosity. From the above results, the rotor bearing system shows complex nonlinear dynamic behavior with nonlinear viscous damping. These results will be helpful to carrying out the optimal design of the rotor bearing system.

scholarly journals Nonlinear Dynamics Analysis of Tilting Pad Journal Bearing-Rotor System

2011 ◽  
Vol 18 (1-2) ◽  
pp. 45-52 ◽  
Author(s):  
Jiayang Ying ◽  
Yinghou Jiao ◽  
Zhaobo Chen
Keyword(s):  
Nonlinear Dynamics ◽  
System Dynamics ◽  
Journal Bearing ◽  
Rotor System ◽  
Moment Of Inertia ◽  
Dynamics Analysis ◽  
Tilting Pad ◽  
Rotor Bearing ◽  
Tilting Pad Journal Bearing ◽  
Bearing System

The nonlinear dynamics theory is increasingly applied in the dynamics analysis of tilting pad journal bearing-rotor system. However, extensive work on system dynamics done previously neglects the influence caused by the moment of inertia of the pad. In this paper, a comparison is made between the responses of the rotor in the bearings with and without pad inertia effect. Taking the Jeffcott rotor system as an example, the characteristics of bearing-rotor system, such as bifurcation diagram, cycle response, frequency spectrum, phase trajectories, and Poincaré maps, were attained within a certain rotation rate range. The pivotal oil-film force of tilting pad journal bearing was calculated by database method. The results directly demonstrate that considering the influence of the pad moment of inertia, system dynamics characteristics are found more complicated when rotor-bearing system works around natural frequency and system bifurcation is observed forward when rotor-bearing system works on high-speed range.

scholarly journals The invariant manifold approach applied to nonlinear dynamics of a rotor-bearing system

2005 ◽  
Vol 24 (4) ◽  
pp. 676-689 ◽  
Author(s):  
Cristiano Viana Serra Villa ◽  
Jean-Jacques Sinou ◽  
Fabrice Thouverez
Keyword(s):  
Nonlinear Dynamics ◽  
Invariant Manifold ◽  
Rotor Bearing ◽  
Bearing System

Review of Nonlinear Rotor-Bearing Dynamics System

2010 ◽  
Vol 37-38 ◽  
pp. 1130-1137 ◽  
Author(s):  
Xing Cong Wu ◽  
Bin Lin ◽  
Feng Liu ◽  
Xue Song Han
Keyword(s):  
Nonlinear Dynamics ◽  
Optimal Design ◽  
Nonlinear Stability ◽  
Coupled System ◽  
Rotating Machinery ◽  
Oil Film ◽  
Analysis Methods ◽  
Rotor Bearing ◽  
Bearing Dynamics ◽  
Bearing System

This article summarizes the research status of nonlinear rotor-bearing dynamics system in china and abroad, discusses several major problems of nonlinear rotor-bearing dynamics system and refers to a large number of references. The review includes the following three aspects: modeling for the nonlinear oil film force of rotor-bearing system; general analysis methods of nonlinear rotor-bearing system; and numerical analysis methods of nonlinear rotor-bearing system. Furthermore, the problems in current research are pointed out, and the development tendencies are also described: further research on the model of nonlinear oil film force; The dimension reduction methods of high-dimensional nonlinear rotor-bearing dynamics system and optimal design of multi-degree of freedom coupled system; nonlinear parameter identification, modeling and reconstruction methods of rotating machinery; optimal design of nonlinear dynamics for large rotating machinery; Research on the sensitivity analysis of nonlinear vibration and the stability, nonlinear stability margin and nonlinear stability criteria of rotor-bearing-basis coupled system; analysis and research on nonlinear dynamics of rotor-bearing-seal system.

Nonlinear Dynamics in the Estimation of Rotor-Bearing Dynamic Properties in Large Hydro-Units*

1999 ◽  
Author(s):  
X. Z. Zhang ◽  
B. G. Liu
Keyword(s):  
Nonlinear Dynamics ◽  
Nonlinear Dynamic ◽  
Natural Frequencies ◽  
Dynamic Properties ◽  
Dynamic Responses ◽  
Dynamic Loads ◽  
Nonlinear Dynamic Response ◽  
Rotor Bearing ◽  
Dynamic Eccentricity ◽  
Bearing System

Abstract This paper describes a method with which the nonlinear dynamic response and the natural features of rotor-bearing systems in large hydro-units can be estimated on a personal computer. The key step of this process is to estimate the dynamic eccentricity of the journal center in every guide bearing when the system is subjected to dynamic loads. As an example, the nonlinear dynamic responses, the natural frequencies and the critical speeds of the rotor-bearing system of a 240MW hydro-unit are calculated. The calculated dynamic responses agree well with the ones measured in the field.

Sign in / Sign up

Export Citation Format

Share Document