A Transient Thermoelastohydrodynamic Analysis of a Tilting-Pad Thrust Bearing During Start-up

2005 ◽  
Author(s):  
X. Wang ◽  
Z. Zhang ◽  
J. Pan
Keyword(s):  
Theoretical Analysis ◽  
Thrust Bearing ◽  
Three Dimensional ◽  
Running Time ◽  
Start Up ◽  
Tilting Pad

The aim of this work is to study the transient thermoelastohydrodynamic behavior of the tilting-pad thrust bearing during its start-up. The theoretical analysis of bearing performance is based on a three dimensional transient TEHD model. The effects of the running time and load on the bearing’s performance are studied. The results show that the above factors influence the performance of the bearing significantly.

Influence of squeezing and interface slippage on the performance of water-lubricated tilting-pad thrust bearing during start-up and shutdown

2018 ◽  
Vol 30 (4) ◽  
pp. 137-148 ◽  
Author(s):  
Zhanchao Wang ◽  
Ying Liu ◽  
Yuechang Wang ◽  
Xiangfeng Liu ◽  
Yuming Wang
Keyword(s):  
Thrust Bearing ◽  
Start Up ◽  
Tilting Pad

The Influence of Injection Pockets on the Performance of Tilting-Pad Thrust Bearings: Part II — Comparison Between Theory and Experiment

2006 ◽  
Author(s):  
Niels Heinrichson ◽  
Axel Fuerst ◽  
Ilmar Ferreira Santos
Keyword(s):  
Film Thickness ◽  
Thrust Bearing ◽  
Three Dimensional ◽  
Leading Edge ◽  
Operating Conditions ◽  
Oil Film ◽  
Thrust Bearings ◽  
Tilting Pad ◽  
High Pressure Injection ◽  
Theoretical Pressure

This is Part II of a two-part series of papers describing the effects of high pressure injection pockets on the operating conditions of tilting-pad thrust bearings. Measurements of the distribution of pressure and oil film thickness are presented for tilting-pad thrust bearing pads of approximately 100 cm2 surface area. Two pads are measured in a laboratory test-rig at loads of approximately 0.5, 1.5 and 4.0 MPa and velocities of up to 33 m/s. One pad has a plain surface. The other pad has a conical injection pocket at the pivot point and a leading edge taper. The measurements are compared to theoretical values obtained using a three dimensional thermoelasto-hydrodynamic (TEHD) numerical model. At low and intermediate loads the theoretical pressure distribution corresponds well to the measured values for both pads although the influence of the pocket is slightly underestimated. At high loads large discrepancies exist for the pad with an injection pocket. It is argued that this is likely to be due to the unevenness of the collar surface. The measured and theoretical values of oil film thickness compare well at low loads. At high loads discrepancies grow to up to 25 %. It is argued that this is due to the accuracy of the measurements.

TEHD analysis of a bidirectional thrust bearing in a pumped storage unit

2016 ◽  
Vol 68 (3) ◽  
pp. 315-324 ◽  
Author(s):  
Liming Zhai ◽  
Zhengwei Wang ◽  
Yongyao Luo ◽  
Zhongjie Li
Keyword(s):  
Thrust Bearing ◽  
Three Dimensional ◽  
Elastic Equilibrium ◽  
Operating Conditions ◽  
Storage Unit ◽  
Content Type ◽  
Thrust Bearings ◽  
Tilting Pad ◽  
Lubrication Characteristics ◽  
Pumped Storage

Purpose The purpose of this paper is to analyze lubrication characteristics of a bidirectional thrust bearing in a pumped storage, considering the effect of the thermal elastic deformation of the pad and collar. Design/methodology/approach This study used the fluid–solid interaction (FSI) technique to investigate the lubrication characteristics of a bidirectional thrust bearing for several typical operating conditions. The influences of the operating conditions and the thrust load on the lubrication characteristics were analyzed. Then, various pivot eccentricities were investigated to analyze the effects of the pivot position. Findings It is found that the effect of the radial tilt angle of the collar runner on the oil film is compensated for by the radial tilt of the pad. The central pivot support system is the main factor limiting the loads of bidirectional thrust bearings. Originality/value This paper has preliminarily revealed the lubrication mechanism of bidirectional tilting-pad thrust bearings. A three-dimensional FSI method is suggested to evaluate the thermal–elastic–hydrodynamic deformations of thrust bearings instead of the conventional method, which iteratively solves the Reynolds equation, the energy equation, the heat conduction equation and the elastic equilibrium equation.

Asymmetry characteristic of tilting-pad thrust bearing during the start-up and shut-down process

2018 ◽  
Vol 70 (9) ◽  
pp. 1806-1814
Author(s):  
Zhanchao Wang ◽  
Fei Guo ◽  
Ying Liu ◽  
Xiangfeng Liu ◽  
Yuming Wang
Keyword(s):  
Velocity Gradient ◽  
Thrust Bearing ◽  
Friction Torque ◽  
Content Type ◽  
Start Up ◽  
Tilting Pad ◽  
Torque Curve ◽  
The Difference ◽  
Thrust Pad ◽  
Squeeze Effect

Purpose This aim of this paper has been to investigate the squeeze effect of a water-lubricated tilting-pad thrust bearing during start-up and shut-down periods. Design/methodology/approach In this paper a numerical model with a squeeze and slippage effect was adopted to analyse the asymmetry characteristic of a tilting-pad thrust bearing during start-up and shut-down periods. A test rig was built to verify numerical results, which were a combined measurement method in which acceleration sensor and torque sensor were used simultaneously to determine the angle change of the thrust pad. Findings It was found that as the velocity gradient increased, the difference of the minimum dimensionless film Hmin could be ignored in the start-up process. But in the shut-down process, as the velocity gradient increased, the value of Hmin also increased, which showed that there was an asymmetry characteristic of the tilting bearing in two processes. This phenomenon was verified by measuring the friction torque curve in the test. Originality/value The results of the studies demonstrated that the velocity gradient could be designed to reduce the friction of the thrust bearing, which would be beneficial to the working life of the tilting-pad thrust bearing.

Static Characteristics of Aerostatic Porous Rectangular Thrust Bearings With Offset Load

1983 ◽  
Vol 105 (1) ◽  
pp. 143-146 ◽  
Author(s):  
K. C. Singh ◽  
N. S. Rao
Keyword(s):  
Theoretical Analysis ◽  
Thrust Bearing ◽  
Three Dimensional ◽  
Porous Matrix ◽  
Operating Parameters ◽  
Static Characteristics ◽  
Dimensionless Form ◽  
Three Dimensional Flow ◽  
Thrust Bearings ◽  
Design Charts

A theoretical analysis for the static characteristics of an aerostatic porous rectangular thrust bearing with an offset load, for both open and sealed end configurations, is presented considering three-dimensional flow in the porous matrix. Static characteristics for different operating parameters are calculated numerically and presented in dimensionless form as design charts. The effect of tilt is discussed.

scholarly journals Influence of the Equalizing Beam Structure on the Water Lubrication Tilting-pad Thrust Bearing during Start-up and Shut-down

2020 ◽  
Vol 56 (1) ◽  
pp. 82
Author(s):  
WANG Zhanchao ◽  
GUO Fei ◽  
LIU Ying ◽  
GONG Changliang ◽  
LIU Xiangfeng ◽  
...  
Keyword(s):  
Thrust Bearing ◽  
Water Lubrication ◽  
Beam Structure ◽  
Start Up ◽  
Tilting Pad

Ultraviolet photodissociation dynamics of PCl3 at 235 nm: three-dimensional ion imaging and theoretical analysis

2021 ◽  
Author(s):  
Alexei Chichinin ◽  
Christof Maul ◽  
Karl-Heinz Gericke
Keyword(s):  
Theoretical Analysis ◽  
Ground State ◽  
Multiphoton Ionization ◽  
Three Dimensional ◽  
Ion Imaging ◽  
Ultraviolet Photodissociation

The photodissociation dynamics of PCl3 at 235 nm has been studied by monitoring ground state Cl(2P3/2) and spin-orbitally excited Cl(2P1/2) atoms by resonance enhanced multiphoton ionization(REMPI). Also, the PCl+n (n=0,1,2)...

Theoretical Analysis and FEM Simulation of Piezoelectric Vibrator Used in Ultrasonic EDM System

2013 ◽  
Vol 694-697 ◽  
pp. 3020-3024
Author(s):  
Hong Bing Wang ◽  
Zhi Rong Li ◽  
Chun Hua Sun
Keyword(s):  
Theoretical Analysis ◽  
Natural Frequencies ◽  
Dynamic Performance ◽  
Three Dimensional ◽  
Fem Simulation ◽  
Model Analysis ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Piezoelectric Vibrator ◽  
Working Frequency

The dynamic performance of the piezoelectric vibrator used in ultrasonic EDM machine in natural frequencies has a great effect on machining precision. Firstly, Through theoretical analysis the dynamic characteristics of the piezoelectric vibrator is obtained. Then the three-dimensional model of the piezoelectric vibrator is constructed by using PRO/E software, and model analysis is carried by using FEM software. Through theoretical analysis and FEM simulation, the appropriate working frequency and mode of the piezoelectric vibrator was found, and the piezoelectric vibrator was fabricated. Experimented results show that the model analysis of frequency is accord with that of FEM.

On the Significance of the Inlet Pressure Build-Up in the Design of Tilting-Pad Bearings

1990 ◽  
Vol 112 (1) ◽  
pp. 17-22 ◽  
Author(s):  
Cz. M. Rodkiewicz ◽  
K. W. Kim ◽  
J. S. Kennedy
Keyword(s):  
Thrust Bearing ◽  
Ambient Pressure ◽  
Inlet Pressure ◽  
Load Carrying Capacity ◽  
Integral Theorem ◽  
Lubricating Film ◽  
Tilting Pad ◽  
Load Carrying ◽  
Momentum Integral ◽  
Entrance Pressure

An operating tilting-pad thrust bearing generates a fore-region which is responsible for maintaining, at the bearing entrance, a pressure which is higher than the ambient pressure. This entrance pressure, in the presented analysis, is obtained by applying to the fore-region the momentum integral theorem. The solution of the lubricating film region is then obtained by using this modified inlet pressure. This solution yields the pressure distribution, the load carrying capacity, the film ratio and the frictional force for several values of the modified Reynolds number and various pivot positions. The analysis shows that there is a significant influence of the fore-region pressure on the bearing performance and that to properly design efficient tilting-pad bearing this effect should be taken into consideration.

Sign in / Sign up

Export Citation Format

Share Document