Comprehensive analysis of dynamic behavior and lubrication performance in a two-cylinder rotary compressor featuring hinge-joined vane and roller

This study presents the novel comprehensive dynamic and lubrication analysis of a two-cylinder rotary compressor incorporating a hinge-joined vane and roller mechanism. A novel contribution lies in the development of complete equilibrium equations for all major components (crankshaft, roller, and vane) explicitly capturing eccentricity and tilting effects. By integrating multibody dynamics simulations with FEM-based solutions of Reynolds equations across sixteen lubrication interfaces, the study reveals critical tribo-dynamic behaviors previously unaddressed. Key findings include minimum oil film thicknesses of 1.56 µm on the roller's bottom surface and 1.0 µm on the vane’s left surface, indicating a transition toward mixed lubrication regimes. The analysis also uncovers significant moment asymmetry at the hinge joints, where the upper joint experiences 10× higher moments than the lower, resulting in enhanced structural tilting and localized lubrication failure risks. Pressure peaks exceeding 14 MPa were observed in the roller's inner surface, confirming it as the dominant friction loss contributor. These results demonstrate the necessity of accounting for coupled eccentricity, tilting, and interfacial interactions in lubrication modeling. The proposed framework provides essential guidance for optimizing hinge-joined rotary compressor designs and improving efficiency, structural integrity, and operational reliability under high-load refrigeration conditions.