Aerodynamic Performance Modeling Method of High-Altitude Propellers Across the Entire Flight Envelope

High-altitude propellers experience diverse aerodynamic conditions, due to the extensive altitude variation and wide range of wind speeds encountered in the flight envelope of High Altitude Long Endurance (HALE) aircraft. Developing a high-precision aerodynamic model requires extensive high-fidelity data. This data is indispensable for aircraft design and control but incurs significant costs. According to the extensive altitude range of HALE aircraft, this paper proposes two efficient and cost-effective modeling methods, the Global Surrogate Model (GSM) and the Stratified Interpolation Surrogate Model (SISM), to acquire the aerodynamic data. Both models are assessed using different performance metrics, including the mean relative error (MRE) and the maximum relative error (MARE), to evaluate their predictive capabilities. The comparative results reveal that the aerodynamic characteristics of high-altitude propellers exhibit highly nonlinear trends in response to changes in altitude. In this study, the two surrogate model construction methods are employed, and it is found that SISM offers superior model accuracy. Specifically, when compared to GSM with an equal number of high-fidelity samples, SISM demonstrates a 2.16% increase in model accuracy. These findings provide a cost-effective approach for HALE propeller modeling.