Optimal weight design of rotor systems with oil-film bearings subjected to frequency constraints

2001 ◽  
Vol 37 (10) ◽  
pp. 777-798 ◽  
Author(s):  
Yih-Hwang Lin ◽  
Sheng-Cheng Lin
Keyword(s):  
Frequency Constraints ◽  
Optimal Weight ◽  
Oil Film ◽  
Rotor Systems ◽  
Weight Design

Minimum weight design of beams in torsional vibration with several frequency constraints

1979 ◽  
Vol 62 (3) ◽  
pp. 411-425 ◽  
Author(s):  
M.H.S. Elwany ◽  
A.D.S. Barr
Keyword(s):  
Torsional Vibration ◽  
Minimum Weight ◽  
Minimum Weight Design ◽  
Frequency Constraints ◽  
Weight Design

Design and Closed Loop Testing of High-Pressure Centrifugal Gas Compressors for the Suppression of Subsynchronous Vibration

1980 ◽  
Vol 102 (1) ◽  
pp. 136-140
Author(s):  
A. F. Criqui ◽  
P. G. Wendt
Keyword(s):  
High Pressure ◽  
Critical Speed ◽  
Closed Loop ◽  
The Other ◽  
Oil Film ◽  
Rotor Systems

The causative phenomena of subsynchronous vibration, or re-excitation of the critical speed of a rotor, are discussed. Two rotor systems designed to control this type of vibration are presented. One system employs tuned, oil film damper bearings while the other features a stiffened rotor geometry. Stability thresholds of each design are compared based on high-pressure closed loop testing.

Research on Coupling Faults With Oil-Film Instability and Bearing Rub-Impact Based on Reassigned Wavelet Scalogram

2007 ◽  
Author(s):  
Xiaopeng Li ◽  
Hui Ma ◽  
Guiqiu Song ◽  
Bangchun Wen
Keyword(s):  
Low Frequency ◽  
Decisive Role ◽  
Frequency Resolution ◽  
Vibration Signals ◽  
Oil Film ◽  
Rotor Systems ◽  
Time Frequency ◽  
Coupling Faults ◽  
Film Instability ◽  
Frequency Components

An experiment rig was set up to simulate coupling faults with oil-film instability and local rub-impact. The collected vibration signals were roughly analyzed by 3-D waterfall spectra. In complicated frequency components domain, the vibration signals were analyzed with wavelet scalogram and reassigned wavelet scalogram. Results show that reassigned wavelet scalogram has higher time-frequency resolution than wavelet scalogram and can well identify such close low-frequency components. The analysis results also indicated rub-impact faults induced by oil-film instability can produce some low-frequency components with small amplitude and oil whip can produce half frequency component; rub-impact with a common extent exerts a light influence on rotor systems and nonlinear oil-film force plays a decisive role in rotor systems.

scholarly journals Optimal Weight Design Approach for the Geometrically-Constrained Matching of Satellite Stereo Images

2017 ◽  
Vol 9 (9) ◽  
pp. 965 ◽  
Author(s):  
Hamed Afsharnia ◽  
Hossein Arefi ◽  
Mohammad Sharifi
Keyword(s):  
Design Approach ◽  
Stereo Images ◽  
Optimal Weight ◽  
Weight Design ◽  
Geometrically Constrained

Optimal weight design problem of elastic structure by GA

2007 ◽  
Vol 53 (2) ◽  
pp. 299-305 ◽  
Author(s):  
Takao Yokota ◽  
Shozo Wada ◽  
Takeaki Taguchi ◽  
Mitsuo Gen
Keyword(s):  
Design Problem ◽  
Elastic Structure ◽  
Optimal Weight ◽  
Weight Design

scholarly journals Identification of Bearing Dynamic Parameters and Unbalanced Forces in a Flexible Rotor System Supported by Oil-Film Bearings and Active Magnetic Devices

Actuators ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 216
Author(s):  
Yinsi Chen ◽  
Ren Yang ◽  
Naohiro Sugita ◽  
Junhong Mao ◽  
Tadahiko Shinshi
Keyword(s):  
Variable Stiffness ◽  
Rotor System ◽  
Unknown Parameters ◽  
Oil Film ◽  
Rotor Systems ◽  
Response Characteristics ◽  
Unbalanced Force ◽  
Displacement Force ◽  
The Stability ◽  
And Control

As the rotational speed of conventional rotor systems supported by oil-film bearings has increased, vibration problems such as oil whip and oil whirl have become apparent. Our group proposed the use of active magnetic bearings (AMBs)/bearingless motors (BELMs) to stabilize these systems. In such a system, measuring the variable stiffness and damping of the oil-film bearings, the current-force and displacement-force parameters of the AMBs/BELMs, and the residual unbalanced force is necessary to satisfy the stability of the rotor system. These parameters are the foundation for the rotor dynamics analysis and optimization of the control strategy. In this paper, we propose a method to simultaneously identify the parameters of the oil-film bearings and AMBs/BELMs along with the residual unbalanced forces during the unbalanced vibration of the rotor. The proposed method requires independent rotor responses and control currents to form a regression equation to estimate all the unknown parameters. Independent rotor responses are realized by changing the PID control parameters of the AMBs/BELMs. Numerical simulation results show that the proposed method is highly accurate and has good robustness to measurement noise. The experimental results show that the unknown parameters identified by the responses generated by different controller parameters are similar. To confirm that the identification results are correct, verification experiments were carried out. The vibration amplitude of the rotor was successfully suppressed by applying a force to the rotor in the opposite direction to the residual unbalanced force. The frequency response characteristics and unbalanced responses of the rotor estimated by the values of the parameters identified show good consistency with the measured results.

Sign in / Sign up

Export Citation Format

Share Document