Aerodynamics And Acoustics Of Da Vinci Aerial Screws

Abstract

This study investigates the aerodynamic and acoustic performance of aerial screws, a helical rotor concept first envisioned by Leonardo da Vinci. Using high-fidelity Computational Fluid Dynamics (CFD) and aeroacoustic simulations, we analyze a range of screw geometries to identify the flow structures and design parameters critical to thrust generation. A dominant mechanism-the formation of a coherent, shape-conforming "da Vinci vortex"-is shown to govern performance, enabling figures of merit up to 0.64 in optimized configurations. Parametric studies reveal that bilinear variations in pitch and taper significantly outperform linear designs by enhancing vortex anchoring and minimizing swirl-induced energy losses. Wake analyses confirm that early contraction and reduced radial dispersion are strong indicators of aerodynamic efficiency. Acoustic evaluations discovered a unique noise radiation pattern for the aerial screws, with perceived noise level similar to or lower than notional conventional rotors operating for same thrust output.