Uncertainty effects of blade geometric deviations on the aerodynamic stability of a high-load transonic axial compressor

This study examines the impact of manufacturing deviations in blade geometry (stagger angle, thickness, chord length, leading edge radius, and trailing edge radius) on the stability margin ( SM ) of a high-load transonic axial-flow compressor. Following the construction of a parametric geometric model for numerical simulations, the NIPC method is applied to quantify the uncertainty effects of manufacturing deviations on the SM . Furthermore, Sobol sensitivity analysis coupled with flow-field analysis is employed to identify the multi-factor effects of the dominant manufacturing deviations and elucidate the underlying nonlinear flow mechanisms. The results indicate that the deviations exert a relatively minor influence on the SM , with the mean value of Δ SM within ±0.03%, and the corresponding approximate ±3 σ interval lying within [−0.3%, 0.3%]. Among these deviations, the stagger angle, thickness, and chord length have relatively significant influences on the SM . Therefore, the multi-factor effects of these three parameters on Δ SM are further evaluated, yielding a mean Δ SM of approximately 0.0163% and an approximate ±3 σ interval of [−0.4604%, 0.4930%]. Sobol sensitivity analysis further identifies blade thickness deviation as the most influential parameter, followed by stagger angle deviation. Flow-field analysis reveals that deviations modify the tip-clearance leakage flow structure and alter the detached shock wave, thereby affecting boundary-layer separation behavior. These flow variations ultimately lead to changes in the compressor stability margin.