Pareto Front Optimization for Spiral-Grooved High-Speed Thrust Bearings: Comparison Between Analytical and Numerical Models

This paper compares two multi-objective optimization strategies for spiral-grooved dynamic gas thrust bearings. The first optimization is carried out using an analytical model, which is valid under the assumption of a high number of grooves. The second one is carried out by using a numerical model based on a finite difference (FD) technique, which is valid also in case of a limited number of grooves. The FD model was validated with data from the literature, then it was compared with the analytical model. The multi-objective optimization is based on a genetic algorithm and it is aimed at maximizing the load-carrying capacity (LCC) of the thrust bearing while minimizing its friction torque. It was found that the analytical model overestimates both the friction torque and the load capacity compared to the FD model, and that the Pareto front optimizations reveal almost identical trends in the optimized parameters.