Simulation studies on static thermal behaviour of true elliptical and orthogonally displaced non-circular journal bearing

Abstract

Purpose

The current trend of modern industry is to use machineries which rotate at high speed along with the capability of carrying heavy rotor loads. This paper aims at static thermal analysis of two different profiles of non-circular journal bearings – a true elliptical bearing and orthogonal bearing.

Design/methodology/approach

The Reynolds equation has been solved through finite difference method to compute the oil film pressure. Parabolic temperature profile approximation technique has been used to solve the energy equation and thus used for computation of various bearing performance characteristics such as thermo-hydrodynamic oil film pressure, temperature, load capacity, Sommerfeld number and power loss characteristics across the bearing. The effect of ellipticity ratio on the bearing performance characteristics has also been obtained for both the elliptical and vertical offset bearing using three different commercially available grades of oil (Hydrol 32, 68 and 100).

Findings

It has been observed that the thermo-hydrodynamic pressure and temperature rise of the oil film is less in orthogonal bearing as compared to the true elliptical bearing for same operating conditions. The effect of ellipticity ratio of non-circularity on bearing performance parameters have been observed to be less in case of elliptical bearing as compared to orthogonal bearing. It has been concluded that though the rise in oil film temperature is high for true elliptical bearing, but still it should be preferred over orthogonal profile under study, as it has comparably good load-carrying capacity.

Originality/value

The performance parametric analysis will help the designers to select such kind of non-circular journal bearing for various applications.

Citation

Singla, A. and Chauhan, A. (2016), "Simulation studies on static thermal behaviour of true elliptical and orthogonally displaced non-circular journal bearing", Industrial Lubrication and Tribology, Vol. 68 No. 3, pp. 349-360. https://doi.org/10.1108/ILT-06-2015-0075