Influence Factor Analysis and Uncertainty Quantification of the Static Characteristics of Organic Working Fluid Aerodynamic Journal Bearings Considering Microscale Effect

The organic working fluid journal bearing is expected to enhance organic Rankine cycle system compactness significantly. In order to serve the practical application of organic working fluid bearings, this study analyzes the influence of key design parameters on the static characteristics under microscale effects. Uncertainty quantification is performed using three methods to address operational deviations. The results reveal the correlations for static characteristic indicators with design parameters in detail. Rarefied gas effects cause negligible pressure deviations (<0.21%), whereas surface roughness significantly improves load capacity. Sensitivity analyses (Morris and Sobol methods) identify eccentricity ratio and gas film thickness as the most influential parameters. KDE results indicate near-normal probability distributions for load and attitude angle. This study provides valuable insights for the design optimization and operational control of organic fluid bearings.