PERFORMANCE ANALYSIS OF HYDRODYNAMIC JOURNAL BEARING WITH THE EFFECT OF WHIRL INSTABILITY
Keywords:
Hydrodynamic Journal Bearing, Whirl Instability, Eccentricity Ratio, Stiffness, Film ThicknessAbstract
Hydrodynamic journal bearings require greater care in design and operation than hydrostatic bearings. They are also more prone to initial wear because lubrication does not occur until there is rotation of the shaft. Oil whirl is when a lubrication wedge can’t form, but instead "whirls" around the bearing, causes tremendous self excitation. This leads to direct contact between the journal and the bearing, which quickly wears out the bearing. This paper represents instability analysis of journal bearings using stiffness estimation at different journal speeds & loads. In this theoretical analysis is presented on journal bearing at 450 N and 1440 r.p.m., which shows that the bearing will remains stable upto a speed of 2378 r.p.m.
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