Data-driven surrogate modeling framework for real-time prediction of airfoil lookup tables: application to proprotor optimization
摘要
Optimization of blade shapes plays a key role in enhancing the aerodynamic efficiency of rotorcraft. However, blade-shape optimization remains challenging due to the strong spanwise variation in local flow conditions experienced by each blade section during rotation. Designers typically employ low-fidelity aerodynamic solvers in rotor blade design due to their computational efficiency. However, these solvers rely on pre-computed airfoil performance lookup tables, making it difficult to treat airfoil shapes as design variables during optimization, thus limiting design flexibility. While surrogate modeling offers a promising solution for real-time generation of airfoil lookup tables, several challenges remain due to the need to account for diverse flow conditions across a broad airfoil design space. To address these challenges, this study proposes an efficient deep-neural-network framework, named Airfoil Brain, which integrates data-driven airfoil parameterization, scalable and reliable surrogate modeling, and an adaptive sampling strategy. Consequently, this framework allows simultaneous consideration of both airfoil and planform parameters in rotor blade-shape optimization. The effectiveness of the proposed framework is demonstrated through a multi-objective aerodynamic optimization of a proprotor.