Role of Offset Factor in Offset-Halves Bearing

Conference paper

Abstract

The present paper aims at presenting the influence of offset factor on the thermal characteristics of offset-halves journal bearing profiles. To study the effect of offset factor, an attempt has been made to the solve the Reynolds’s equation and energy equation using finite difference method on the performance characteristics such as oil-film temperatures, thermal pressures, load carrying capacity, power loss, and Sommerfeld’s number of offset-halves journal bearing. To carry the numerical solution of Energy equation, the author has used Parabolic Temperature Profile Approximation technique in order to achieve faster computation. It has been observed that at constant radial clearance, a decrease in oil-film temperature, thermal pressure, load carrying capacity and an increase in Sommerfeld’s number obtained with an increase in offset factor. During the study, it has been concluded that the offset factor significantly affects the performance parameters of the bearing under study and may be kept equal to around 0.4 to get the desired thermal characteristics.

Keywords

Load carrying capacity Offset-halves bearing Offset factor Oil-film temperature Sommerfeld number Thermal pressure 

Nomenclature

e

Eccentricity, m

OB

Bearing centre

Oj

Journal centre

OL

Lower-lobe centre

OU

Upper-lobe centre

P

Film pressure, Pa

R

Journal radius, mm

r

Bush radius, mm

T

Lubricating film temperature, °C

U

Relative velocity between journal and bearing surface, m/s

u, w

Velocity components in X- and Z-directions, m/s

uL

Velocity of lower bounding surface, m/s

uU

Velocity of upper bounding surface, m/s

θ

Angle measured from horizontal split axis in direction of rotation

ω

Angular velocity of shaft, rad/s

φ

Attitude angle

ɛ

Eccentricity ratio

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Copyright information

© Springer Science+Business Media Dordrecht 2014

Authors and Affiliations

  1. 1.Department of Mechanical Engineering, UIETPanjab UniversityChandigarhIndia

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