Hydrodynamic Deformable Rough Conical Journal Bearing

Many turbo-machines, such as turbines and compressors, generate both axial and radial loads during operation. A conical hydrodynamic journal bearing is proposed to support the radial load and mitigate the effects of axial load on rotating components. This study presents a performance analysis of conical hydrodynamic journal bearings with semi-cone angles (c = 5°, 10°, 20°, 30°) over a wide range of radial loads (W*r = 0.1 – 0.9) on a rotating journal. The Finite Element Method (FEM) is employed to solve the modified Reynolds equation, allowing for the investigation of lubricant flow within the clearance space between the journal and bearing. The performance characteristics, such as load-carrying capacity, fluid film thickness, stiffness coefficients, damping coefficients, and threshold speed, are analyzed for various configurations of the conical hydrodynamic journal bearing. The results show that the threshold speed (?*th) of the conical journal bearing significantly decreases as the semi-cone angle increases to c = 30° compared to the base bearing with a semi-cone angle of c = 5°.