Rotating Shaft Stability in Entire Region of Equilibrium in Multilobe Bearings.

For their known advantages of low cost and relatively high stability of operation, the multilobe bearings have found prevalent industrial applications. To more clearly define the limit of usability for each of 2-lobe, 3-lobe and 4-lobe bearings, we studied in detail the rotating shaft stability at whole region of equilibrium in these multilobe bearings. Consequently, we found that the angles at which the multilobe bearings were installed could significantly influence the shafting stability. Also, we devised a new method capable of determining quantitatively the shafting natural frequency and damping ratio at any point of equilibrium in the multilobe bearings.