Uncertainty effect of leading edge fouling on aerodynamic performance of compressor cascades

To investigate the uncertainty effects of leading edge fouling (Fouling-LE) on aerodynamic performance, uncertainty models are developed by integrating fouling thickness distribution with sparse grid techniques. The results indicate that Fouling-LE uncertainty reduces the available range of negative incidence by 2.5°, increases the likelihood of aerodynamic performance degradation (pressure ratio π and loss ω), raises the probability of a lower airflow turning angle, and introduces a significant risk of flow instability across all incidences. Specifically, the probability of Fouling-LE causing π to exceed the stable operating range is 16.14 % and 10.08 %, while the probability of ω exceeding the stable operating range is 9.88 % and 16.25 %, at the incidence of i=-2.5° and 7°, respectively. The influence of Fouling-LE on the flow field progressively extends downstream, altering the aerodynamic loading on the blade surfaces and inducing a forward shift in the transition position.