Effect of Operating Condition and Structural Parameter in the Hydrostatic Thrust CO2 Bearing

Abstract

Hydrostatic thrust bearings are widely applied in rotating machinery field. Its comprehensive performance and safe operation is of great significance for ensuring equipment efficiency. In this paper, the numerical method is adopted to investigate the slit-restricted hydrostatic thrust CO2 bearing with a small film thickness. The research is carried out from two aspects, which mainly consider the operating conditions and structural parameters. Firstly, the influence of different working fluid types including real air and CO2 (include subcritical and supercritical state) on the static characteristics of bearing is studied, and the results indicate that the bearing with CO2 as working fluid has a better static performance. Secondly, the influence of rotor rotating speed is studied and the conclusion shows that the rotating speed has a significant effect on bearing static characteristics. Thirdly, the influence of different slit arrangement forms is investigated, and the consequence indicates that the circumferential slits show a better load capacity than that of radial slits, while the flow rate difference is small. Finally, the effect of film thickness on bearing static performance is investigated and the research shows that this factor affects static performance in a dramatical way. When the clearance tends to be smaller, the load capacity increases sharply, while the massflow rate of working fluid decreases.