A computational model for the hydrostatic auxiliary lubrication performance of large hydrodynamic thrust bearings was established to investigate their behavior at low and rated speeds. This study focused on analyzing the influence of different hydrostatic oil cavity shapes (circular, annular, and rectangular) and oil supply pressures on key lubrication parameters: minimum oil film thickness (hmin), power consumption (W), flow rate (Q), and temperature rise ( \(\Delta\) T).The results indicate that: During low-speed start-up, hydrostatic assistance significantly enhances the bearing’s load capacity and lubrication performance. Among the three cavity shapes, the circular cavity provided the best auxiliary effect, yielding a larger hmin and lower W compared to annular and rectangular shapes. At rated speed, the oil supply pressure is a critical factor. When the supply pressure is sufficiently high, hydrostatic assistance significantly improves bearing performance (hmin increased by 84.7%, W decreased by 21.6%). However, when the supply pressure drops below a critical threshold, the hydrostatic cavity acts as a “drain hole,” causing a loss of oil film pressure and deteriorating lubrication performance. This study provides a quantitative basis for the design of hydrostatic auxiliary systems in large thrust bearings.
