An improved meanline method for enhancing the prediction accuracy of compressor performance: Some novel perspectives in models and methodology

The meanline method serves as a fundamental tool for axial compressor design, yet its accuracy is fundamentally constrained by empirical model uncertainties and stage-to-meanline performance discrepancies. To address these limitations, enhanced performance correlations between reference streamlines and complete compressor stages have been developed in this study, while empirical models have been improved through comprehensive database analysis. The refined models exhibit exceptional precision, with incidence angle errors within ±1°, deviation angle errors below 2°, and loss coefficient errors of ±0.02–0.03. A novel equivalent blockage factor (Kb) is introduced to physically couple reference streamline velocity triangles with stage performance characteristics, effectively accounting for three-dimensional flow effects. Validation results show maximum design point errors of 4.29% in pressure ratio and 1.45% in efficiency for stages 35–38. Multistage simulations exhibit greater error magnification compared to single-stage analyses, reflecting the inherent error propagation characteristics of the meanline methodology. These findings contribute to the advancement of compressor design practice through both improved predictive accuracy and fundamental elucidation of meanline-to-stage performance relationships.