The present work deals with numerical investigation into geometric imperfection (bellmouth, undulation and barrel shape) of the journal on performance of a porous hybrid journal bearing system (PHJBs) operating under turbulent flow condition. The Reynolds equation governing the flow of lubricant in the bearing clearance space is modified by using the turbulent lubrication theory proposed by Constantinescu’s. The bearing performance parameters are numerically computed using FEM. The effects of geometric irregularities, turbulent flow condition, and permeability parameters have been investigated on the performance of PHJBs. The theoretically obtained results indicates that the combined effect of turbulent flow condition and geometric imperfection offers enhanced values of and rotor dynamic coefficients (stiffness and damping coefficients).
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