The effect of biolubricants oil on the dynamic performance of rotor bearing system

The effect of using blend of biolubricant oil with mineral lubricant oil on the dynamic behaviour of rotor bearing system has been investigated analytically and numerically. The using of blend of different lubricant oils in fluid film journal bearing lubrication systems can be using when their effect leads to enhancing of the dynamic performance of bearing. The finite element method has been used to modelling rotor and bearings. The results of this study clearly showed that the using of biolubricant alone as lubricant oil led to reduce the dynamic response to a significant level up to 37.3% while the blend of 90%ISO VG46 with 10%Jatropha and 70%ISO VG46 with 30%Jatropha led to reduce the dynamic response by 3.7% and 11.9% respectively. The using of different blend of the biolubricant oil with the mineral oil has no effect on the critical speed of rotor. The blend of biolubricant oil with mineral oil when used as a lubricant oil in the journal bearing led to decreasing most bearing parameters such as attitude angle, Somerfield number, oil reaction forces and oil pressure while the thickness of the lubricant oil was not changed by using different oils types.