Abstract: A misaligned journal bearing is taker as research object, and its lubrication model is built with consideration of couple stress lubricant area and viscosity-pressure effect. In order to explore the sensitivity of couple stress fluid to oil film thickness, the critical oil film thickness coefficient is introduced. Then the influence of couple stress lubricant calculation area, misaligned angle, viscosity-pressure effect and couple stress parameter on bearing lubrication characteristics are studied. The result shows that: the response sensitivity of lubrication performance on oil film thickness grows with the increase of couple stress parameter and it comes highest on the area of min oil film thickness. Comparing with the Newton lubricant, the bearing oil film pressure increases obviously when considering the effect of couple stress, and the bearing oil film pressure comes higher and friction coefficient comes lower when more couple stress areas were taken into consideration. The effect of lubricant couple stress increases when the journal is misaligned, and the effect grows with the increase of couple stress parameter. Viscosity-pressure effect takes an important role in bearing oil film pressure which lubricated couple stress lubricant, but its effect is relatively low on frictional coefficient and end leakage flow rate.

Key words: misaligned journal bearing, couple stress consideration area, viscosity-pressure effect, lubrication characteristics