Efficiency–Noise Trade–Off of Downscaled eVTOL Tiltrotor: A Low–Fidelity Multiobjective Optimisation Framework

Kurzfassung

A low-fidelity multiobjective optimisation framework is developed for the aeroacoustic design of a low-Reynolds-number tiltrotor blade of an electric vertical take-off and landing (eVTOL) aircraft. The framework couples a blade element momentum method with airfoil polars generated with an XFoil-informed neural network, an analytical tonal-noise model, and an Euler–Bernoulli structural analysis. A Kriging surrogate explores a 41-dimensional geometric design space. The application to a one-tenth scaled five-bladed front rotor yields a physically consistent Pareto front between cruise efficiency and tonal sound power. Three favourable blade designs are selected for further analysis, each trading at most 7.8 % efficiency gain for up to 14 dB sound power reduction. The study delivers the Pareto landscape and methodological insights that inform a subsequent high-fidelity optimisation.