An Experimental Study of Oil-Lubricated Journal Bearings Undergoing Oscillatory Motion

2008 ◽  
Vol 130 (2) ◽  
Author(s):  
Xiaobin Lu ◽  
M. M. Khonsari
Keyword(s):  
Experimental Study ◽  
Hysteresis Loop ◽  
Journal Bearing ◽  
Journal Bearings ◽  
Oscillatory Motion ◽  
Hydrodynamic Regime ◽  
Inlet Temperature ◽  
Lubricant Flow ◽  
Series Of Experiments ◽  
Oil Type

A distinctive behavior of an oil-lubricated journal bearing undergoing oscillatory motion is the evolution of friction hysteresis as it traverses from boundary, to mixed, and to hydrodynamic regime. In this paper, the results of a series of experiments are reported to examine the effects of load, with or without oil, oil type, oil inlet temperature, and oscillating frequency on the friction hysteresis. Three types of hysteresis loop were found. The inertia of the lubricant flow contributes to the friction hysteresis.

An Experimental Study of Grease-Lubricated Journal Bearings Undergoing Oscillatory Motion

2007 ◽  
Vol 129 (3) ◽  
pp. 640-646 ◽  
Author(s):  
Xiaobin Lu ◽  
M. M. Khonsari
Keyword(s):  
Experimental Study ◽  
Hysteresis Loop ◽  
Journal Bearings ◽  
Oscillatory Motion ◽  
Hydrodynamic Regime ◽  
Series Of Experiments

A series of experiments was performed to study the behavior of grease-lubricated journal bearings. The results reveal that an oscillatory bearing undergoes a transition from boundary, to mixed, and to hydrodynamic regime. Another distinct feature is friction hysteresis that occurs as a result of oscillation. In this paper, we examine the effect of load, oscillating frequency, and lubricant on the friction hysteresis loop.

Paper 15: Thermal Aspects of Hydrodynamic Journal Bearing Performance at High Speeds

1966 ◽  
Vol 181 (15) ◽  
pp. 127-135 ◽  
Author(s):  
R. G. Woolacott ◽  
W. L. Cooke
Keyword(s):  
Flow Rate ◽  
Journal Bearing ◽  
Journal Bearings ◽  
Inlet Temperature ◽  
Flow Rates ◽  
High Speeds ◽  
Lubricant Flow ◽  
Hydrodynamic Journal Bearing ◽  
Temperature And Pressure

This paper describes a rig for testing journal bearings at high speeds under steady loads and reports on measurements of bearing and lubricant temperatures and lubricant flow-rates for hydrodynamic journal bearings operating at speeds up to 35 000 rev/min and mean bearing pressures up to 3333 lbf/in2. Variations of temperature and flow-rate with load, speed, oil-inlet temperature and pressure, clearance, and oil-inlet grooving are also described, and the effects of bearing and lubricant temperatures on bearing performance are discussed.

Experimental Analysis of Journal Bearings Undergoing Oscillatory Motion

2007 ◽  
Author(s):  
Xiaobin Lu ◽  
Michael M. Khonsari
Keyword(s):  
Friction Coefficient ◽  
Thermal Field ◽  
Journal Bearing ◽  
Journal Bearings ◽  
Oscillatory Motion ◽  
Temperature History ◽  
The Finite Element Method ◽  
History Of ◽  
Series Of Experiments ◽  
Good Agreement

A series of experiments is carried out on a grease-lubricated, heavy loaded journal bearing undergoing oscillatory motion to examine its thermal field. The history of temperature measurement and the friction coefficient are monitored. The finite element method is employed using ANSYS to simulate the temperature history with input of the friction coefficient result. Experiment and simulation show good agreement.

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.

An Approximate THD Theory for Journal Bearings

1990 ◽  
Vol 112 (2) ◽  
pp. 224-229 ◽  
Author(s):  
G. Gupta ◽  
C. R. Hammond ◽  
A. Z. Szeri
Keyword(s):  
Journal Bearing ◽  
Load Capacity ◽  
Pressure Coefficient ◽  
Journal Bearings ◽  
Maximum Pressure ◽  
Substantial Agreement ◽  
Interactive Mode ◽  
Lubricant Flow ◽  
Bearing Load ◽  
Sophisticated Model

The aim of this paper is to make available to the industrial designer results of the thermohydrodynamic theory of journal bearings, by providing a simplified, yet accurate model of journal bearing lubrication that can be implemented on a personal computer and be used in an interactive mode. The simplified THD theory we propose consists of two coupled ordinary differential equations for pressure and energy and an algebraic equation for viscosity, which are to be solved iteratively. Bearing load capacity, maximum bearing temperature, maximum pressure, coefficient of friction and lubricant flow rate calculated from this simplified theory compare well with results from a more sophisticated model. We also make comparisons with experimental data on full journal bearings, demonstrating substantial agreement between experiment and simplified theory.

Experimental Study of Tilting-Pad Journal Bearings—Comparison With Theoretical Thermoelastohydrodynamic Results

1992 ◽  
Vol 114 (3) ◽  
pp. 579-587 ◽  
Author(s):  
Michel Fillon ◽  
Jean-Claude Bligoud ◽  
Jean Freˆne
Keyword(s):  
Experimental Study ◽  
Theoretical Model ◽  
Rotational Speed ◽  
Journal Bearing ◽  
Journal Bearings ◽  
Operating Conditions ◽  
Operating Characteristics ◽  
Tilting Pad ◽  
Tilting Pad Journal Bearing ◽  
Tilting Pad Journal Bearings

Operating characteristics of four-shoe tilting-pad journal bearings of 100 mm diameter and 70 mm length are determined on an experimental device. The load, between pad configuration, varies from 0 to 10,000 N and the rotational speed is up to 4000 rpm. Forty thermocouples are used in order to measure bearing element temperatures (babbitt, shaft, housing and oil baths). The influence of operating conditions and preload ratio on bearing performances are studied. Comparison between theoretical and experimental results is presented. The theoretical model is also performed on a large tilting-pad journal bearing which was investigated experimentally by other authors.

Analysis of Multirecess Hydrostatic Journal Bearing Operating With Micropolar Lubricant

2009 ◽  
Vol 131 (2) ◽  
Author(s):  
Suresh Verma ◽  
Vijay Kumar ◽  
K. D. Gupta
Keyword(s):  
Reynolds Equation ◽  
Theoretical Study ◽  
Journal Bearing ◽  
Journal Bearings ◽  
Performance Characteristics ◽  
Constant Flow ◽  
The Finite Element Method ◽  
Lubricant Flow ◽  
Wide Range ◽  
Flow Valve

This paper presents a theoretical study of the performance characteristics of a constant flow valve compensated multirecess hydrostatic journal bearings operating with micropolar lubricant. The finite element method and iterative procedure have been used to solve the modified Reynolds equation governing the micropolar lubricant flow in the bearing. The performance characteristics are presented for a wide range of nondimensional load, lubricant flow, and micropolar parameters. It has been observed that the micropolar parameters significantly influence the performance characteristics of the bearing.

Experimental study for performance evaluation of steadily loaded true elliptical and orthogonally displaced non-circular journal bearing profiles

2016 ◽  
Vol 68 (6) ◽  
pp. 702-711 ◽  
Author(s):  
Amit Singla ◽  
Amit Chauhan
Keyword(s):  
Experimental Study ◽  
Thermal Performance ◽  
Journal Bearing ◽  
Journal Bearings ◽  
Maximum Temperature ◽  
Positive Pressure ◽  
Film Pressure ◽  
Content Type ◽  
Oil Film ◽  
Oil Film Pressure

Purpose The non-circular journal bearings may be used over circular journal bearings because of their superior thermal stability. The paper aims at experimental study of thermal performance of two different true elliptical and orthogonally displaced non-circular journal bearing profiles. Design/methodology/approach The experiments have been conducted on a specially designed test rig which simultaneously evaluates oil film pressure and temperature along the circumference of non-circular journal bearing. The tests are conducted for the designed true elliptical and orthogonally displaced journal bearing at three different rotational speeds of 2,000, 3,000 and 4,000 rpm under the influence of steadily applied load varied from 0.5 to 2.0 kN. The data collected during experimentation have been used to evaluate thermal performance parameters such as maximum pressure, flow rate and effective temperature of the bearings under study. Findings It has been observed experimentally that two lobes of pressure and temperature have been obtained for both the elliptical and orthogonally displaced journal bearing. The negative pressure zone (cavitation area) has been observed to be reduced along the circumference for both the journal bearings which results in less thermal degradation of an oil as compared to circular journal bearing. The oil film pressure and temperature increases with the increase in radial load of both the bearings. The maximum temperature rise of oil film is more in case of elliptical bearing as compared to the orthogonally displaced bearing. Originality/value The experimental data presented in this paper will help the designers to select such kind of non-circular journal bearing for various applications. The designed bearings have resulted in reduced cavitation zone and two positive pressure lobes have been observed which may result in application of such bearings as an alternate for circular journal bearing.

Journal Bearing Lubrication and Design

1948 ◽  
Vol 158 (1) ◽  
pp. 250-254
Author(s):  
A. S. T. Thomson
Keyword(s):  
Experimental Investigation ◽  
Applied Load ◽  
Journal Bearing ◽  
Point Contact ◽  
Journal Bearings ◽  
Operating Conditions ◽  
Experimental Results ◽  
Radial Clearance ◽  
Series Of Experiments ◽  
Loaded Side

The paper summarizes the results of an experimental investigation on the effects of variation in bearing width and radial clearance on the operating conditions of centrally loaded clearance journal bearings, the bearing arc being kept constant at 120 deg. The investigation, which was carried out prior to 1940, is complementary to an earlier paper by the author in which the effects of variations in bearing width and arc of embrace were investigated. The experimental results are compared with theoretical values modified by the relevant leakage coefficients. The measure of agreement obtained indicates that theoretical values so modified may be used with confidence in design. A short series of experiments is described; in these, high-point contact at starting and stopping is eliminated by supplying oil to a groove in the loaded side of the bearing at a pressure sufficiently great to overcome the applied load. The effect of a groove on the loaded side of the brass under various conditions of lubrication is investigated.

Experimental Study of Stabilisation of Small Size Journal Bearing With Oil Supply Groove by Using Starved Lubrication and Bearing Orientation Angle Change

2007 ◽  
Author(s):  
Masayuki Ochiai ◽  
Hiromu Hashimoto
Keyword(s):  
Experimental Study ◽  
High Speed ◽  
Journal Bearing ◽  
Orientation Angle ◽  
Journal Bearings ◽  
Rotating Machinery ◽  
Angle Change ◽  
Tilting Pad ◽  
Starved Lubrication ◽  
Rotating Machineries

Journal bearings are widely used for supporting high speed rotating machinery such as turbine, compressor and HDD spindle etc, because of their high load carrying capacity, stability and durability. Recently, the engineering trend is oriented to higher speed and smaller sizes of rotating machinery, and then it is important to enhance stabilities for the journal bearings. Tilting pad journal bearing is generally used for high-speed rotating machineries because of their advantages of stabilization. However, there are some problems using for compact size rotating machineries for their high manufacturing cost and complicated structure. Therefore, it is necessary to enhance the stability of more simple bearings compared with tilting pad bearing in order to use for small size rotating machinery. This paper describes the stabilization method of journal bearing based on the combination mechanism with starved lubrication and orientation angle change. From the results of stability experimental study of journal bearings, it is clarified that the stabilization of bearings is improved drastically by using above techniques.

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