Journal Bearing and Radial Seal Rotor Dynamics

2017 ◽  
pp. 49-63
Author(s):  
Maurice L. Adams
Keyword(s):  
Journal Bearing ◽  
Rotor Dynamics

Jørgen W. Lund: Theories Versus Tests, Part 1: Balancing and Response of Flexible Rotors

2003 ◽  
Vol 125 (4) ◽  
pp. 482-488 ◽  
Author(s):  
Jørgen Tonnesen
Keyword(s):  
Experimental Work ◽  
Journal Bearing ◽  
Rotor Dynamics ◽  
Flexible Rotor ◽  
Late Professor ◽  
Fluid Film Bearings ◽  
Condensed Form ◽  
Flexible Rotors ◽  
The Subject ◽  
Rotor Balancing

The contribution of the late Professor Jørgen W. Lund in the field of rotor dynamics and fluid film bearings is presented in a condensed form with the emphasis on the experimental work and results that confirm and support many of Dr. Lund’s theories and analyses. Part 1(A) covers the subject of rotor balancing by the influence method and Part 1(B) the unbalance response of a flexible rotor. In Part 2(A), experiments on instability and the influence of unbalance on whirl frequency are discussed for two rotors supported in cylindrical bearings. In Part 2(B), experiments using a cylindrical, two-axial groove journal bearing over a range of loads and speeds are reviewed.

Short Bearing Analysis Applied to Rotor Dynamics—Part 2: Results of Journal Bearing Response

1976 ◽  
Vol 98 (2) ◽  
pp. 319-329 ◽  
Author(s):  
R. G. Kirk ◽  
E. J. Gunter
Keyword(s):  
Transient Response ◽  
Journal Bearing ◽  
Rotor Dynamics ◽  
Journal Bearings ◽  
Radius Of Curvature ◽  
Extensive Investigation ◽  
Stability Threshold ◽  
Stability Maps ◽  
And Performance ◽  
The Stability

The results of an extensive investigation of the transient response of rotors supported in fluid-film journal bearings is presented in the form of computer generated orbits of rotor motion. The stability of the rotor-bearing system was determined by examination of the system characteristic equation in Part 1. Rotor transient response orbits demonstrate the rotor behavior below and above the stability threshold. The results show the effect of imbalance, steady loading, cyclic unidirectional and rotating loads upon the stability and performance of a short journal bearing. The results are compared to previous investigations and modified stability maps are deduced from the results obtained. The concept of whirl is examined and several plots presented of the instantaneous whirl ratio and radius of curvature versus cycles of motion (of the journal) for the various cases considered. Bearing forces are analyzed and the resulting plots of force versus cycles of motion are presented for selected cases.

Nonlinear Effects in a Plain Journal Bearing: Part 2—Results

1991 ◽  
Vol 113 (3) ◽  
pp. 563-570 ◽  
Author(s):  
M. J. Braun ◽  
F. K. Choy ◽  
Y. Hu
Keyword(s):  
Reynolds Equation ◽  
Journal Bearing ◽  
Nonlinear Effects ◽  
Rotor Dynamics ◽  
Inlet Temperature ◽  
Dynamics Model ◽  
Nonlinear Characteristics ◽  
Pressure Profiles ◽  
Input Variables ◽  
Bearing Part

Part 1 of this paper presented a numerical model that coupled the variable property Reynolds equation with a rotor dynamics model for the calculation of the nonlinear characteristics of a plain journal bearing working with a cryogenic fluid (LO2). Part 2 will present the numerical results yielded by the model that used (a) lubricant inlet temperature, (b) external load, (c) angular rotational speed, and (d) axial misalignment as input variables for the parametric study. The resulting pressure profiles and linear and nonlinear characteristics of the bearing are discussed and their inter-relationship is analyzed.

scholarly journals Multi Body Analysis Of A Turbocharger Supported By A Fully Floating Ring Bearing

2015 ◽  
Vol 13 (1) ◽  
pp. 7-11
Author(s):  
Jiří Knotek ◽  
Pavel Novotný ◽  
Ondřej Maršálek ◽  
Peter Raffai
Keyword(s):  
Hydrodynamic Model ◽  
Reynolds Equation ◽  
Journal Bearing ◽  
Rotor Dynamics ◽  
Dynamics Analysis ◽  
Multi Body ◽  
Advanced Tool ◽  
Rotor Model

Abstract This paper describes an advanced tool for turbocharger rotor dynamics analysis and its development. The hydrodynamic model of the journal bearing based on Reynolds equation is presented. The paper also describes assembly of the turbocharger rotor model. At the end the basic results are presented and analyzed.

Misalignment Effect on Cement Kiln Support Bearing

2008 ◽  
Author(s):  
P. Samanta ◽  
Barun Chakrabarti ◽  
S. V. Herwadkar
Keyword(s):  
Journal Bearing ◽  
Rotor Dynamics ◽  
Cement Kiln ◽  
Load Carrying Capacity ◽  
Performance Parameters ◽  
Damping Coefficients ◽  
Dynamic Coefficients ◽  
Load Carrying ◽  
Minimum Film Thickness ◽  
Elastic Coefficients

This paper illustrates the effect of misalignment on performance of cement kiln partial journal bearing. The performance parameters include minimum film thickness, load carrying capacity, power loss and dynamic coefficients such as elastic coefficients and damping coefficients. The bearing analyses have been carried out using a commercial rotor dynamics software package.

Effects of bearing lubrication conditions on rotor dynamic behavior

2021 ◽  
pp. 135065012110105
Author(s):  
Barbara Z Cunha ◽  
Gregory B Daniel
Keyword(s):  
Dynamic Behavior ◽  
Journal Bearing ◽  
Rotor Dynamics ◽  
Feeding Condition ◽  
Flow Rates ◽  
Supply Condition ◽  
Dynamic Analyses ◽  
Feeding Pressure ◽  
Rotor Dynamic ◽  
Lubrication Conditions

Usually, rotor dynamic analyses do not consider the effects of the lubricant supply condition, although this is an important aspect of journal bearing performance. Therefore, this work has implemented a mass-conserving model to realistically describe the oil feeding condition and evaluate its influence on rotor dynamics. This analysis was carried out by varying feeding pressure and groove position and the results indicate that the oil supply conditions significantly influence the bearing performance and affect the dynamic behavior of the entire rotor. In general, lower flow rates lead to a bearing with a greater stability region, as observed mainly in the bearing with a groove at 270° and, on the other hand, the increase in feeding pressure reduces the instability threshold.

scholarly journals Influence of Journal Bearing Axial Grooves on the Dynamic Behavior of Horizontal Rotors

2006 ◽  
Vol 13 (4-5) ◽  
pp. 285-300 ◽  
Author(s):  
Miguel Angelo de Carvalho Michalski ◽  
Moysés Zindeluk ◽  
Renato de Oliveira Rocha
Keyword(s):  
Experimental Study ◽  
Dynamic Behavior ◽  
Journal Bearing ◽  
Rotor Dynamics ◽  
Journal Bearings ◽  
Test Rig ◽  
Rotating Machine ◽  
Lubricant Flow ◽  
Non Linear ◽  
Bearing Design

Journal bearing design and the lubricant characteristics are very influential in a rotating machine behaviour. The bearing geometry can drastically affect the lubricant flow and also the rotor dynamics. Approaching that issue, this paper presents an experimental study of the dynamic behavior of a horizontal rotor suported by journal bearings with semi-circular axial grooves. The journal bearings were manufactured with a varied number of axial grooves and a versatile test rig is used, making possible the analysis of different configurations. The acquired signals are analyzed with classical and non-linear tools and the differences among the rotors’ configurations can be shown.

Quantum Mechanical Interpretation of the Ultra-Low Energy Methyl-Rotation Dynamics in Porous Metal-Organic Frameworks Probed by Low-Frequency Vibrational Spectroscopy and ab initio Simulations

2018 ◽  
Author(s):  
Qi Li ◽  
Adam J. Zaczek ◽  
Timothy M. Korter ◽  
J. Axel Zeitler ◽  
Michael T. Ruggiero
Keyword(s):  
Ab Initio ◽  
Metal Organic Frameworks ◽  
Low Frequency ◽  
Rotor Dynamics ◽  
Quantum Mechanical ◽  
Valuable Insight ◽  
Void Space ◽  
Ab Initio Simulations ◽  
Metal Organic ◽  
Insight Into

<div>Understanding the nature of the interatomic interactions present within the pores of metal-organic frameworks</div><div>is critical in order to design and utilize advanced materials</div><div>with desirable applications. In ZIF-8 and its cobalt analogue</div><div>ZIF-67, the imidazolate methyl-groups, which point directly</div><div>into the void space, have been shown to freely rotate - even</div><div>down to cryogenic temperatures. Using a combination of ex-</div><div>perimental terahertz time-domain spectroscopy, low-frequency</div><div>Raman spectroscopy, and state-of-the-art ab initio simulations,</div><div>the methyl-rotor dynamics in ZIF-8 and ZIF-67 are fully charac-</div><div>terized within the context of a quantum-mechanical hindered-</div><div>rotor model. The results lend insight into the fundamental</div><div>origins of the experimentally observed methyl-rotor dynamics,</div><div>and provide valuable insight into the nature of the weak inter-</div><div>actions present within this important class of materials.</div>

Sign in / Sign up

Export Citation Format

Share Document