An investigation into the performance characteristics of MR-lubricated conical hybrid thrust bearings

Abstract

The conical bearings are capable of supporting combined radial and axial loads, their performance at higher semi-cone angles—particularly under heavy thrust loads—has received minimal attention in the literature. Therefore, this study aims to achieve improved bearing performance of conical hybrid thrust bearing (CHTB) lubricated with Magneto-Rheological (MR) lubricant under heavy thrust load requirements. In this paper, the modified Reynolds equation governing the bearing fluid domain is discretized using the finite element method (FEM) and solved via the Newton–Raphson technique. The flow behaviour of the MR lubricant is modelled using the Dave equation, based on the Bingham plastic rheological model. The effect of restrictor design parameter, axial shaft position and semi-cone angle is systematically investigated to examine the static and dynamic behaviour of the bearing. A parametric study of recess dimensions is also performed, and the optimum recess geometry is identified based on stiffness characteristics. The numerical results indicate that the use of MR lubricant, particularly at lower shaft positions and higher semi-cone angles, significantly enhances load capacity, maximum lubricant pressure, lubricant flow rate, and damping coefficient. Also, at a particular value of restrictor design parameter, the stiffness coefficient provides the optimum performance. The findings provide important insights into the coupled influence of restrictor design parameter, axial shaft position and semi-cone angle of conical hybrid thrust bearing (CHTB) operating with both Newtonian and MR lubricants.