Optimization of a Herringbone Grooved Thrust Bearing

This paper analyses a state-of-art model of herringbone grooved thrust bearings (HGTB), i.e. dynamic gas journal bearings widely employed in various very high-speed applications where friction reduction is a key aspect. After the presentation of the state of the art about the applications of such bearings, the simplified analytical model from Whipple is briefly reviewed and the main simplifying assumptions are highlighted. This model provides a first approximation of the behavior of HGTB. Whipple model is then applied for the design of micro thrust bearings for a micro turbo-compressor applied in fuel cells systems. A sensitivity analysis is carried out to evaluate the effect of the main geometrical parameters on the maximum pressure and on the load capacity of the thrust bearing. The specific operative conditions of the given application are considered in the analysis. Finally, the geometry is optimized in order to maximize the load capacity within the bounds of the geometrical constraints of the application.