Mixed elastohydrodynamic analysis of a coupled journal-thrust bearing system in a rotary compressor under high ambient pressure

Abstract The hermetic rotary compressor’s bearings, including the thrust bearing, the main and sub bearings, work together under high ambient pressure. The thrust bearing works under light axial loads, but sever wear is found, which may be related to the crankshaft’s misalignment and deformation and the high ambient pressure. To investigate this phenomenon, a complete coupled journal-thrust bearing model is constructed. The bearing forces are calculated with the mixed elastohydrodynamic model under high boundary pressure. The effects of the deformations and ambient pressure on the bearing performance are investigated. Results show that ignoring the crankshaft deformation makes the simulation underestimate the thrust bearing wear, and the high ambient pressure is the leading cause of the thrust bearing wear.