Aerodynamics and Aeroacoustics of da Vinci's Aerial Screw

TL;DR

This study uses numerical simulations to analyze the aerodynamics and noise of a modernized da Vinci aerial screw, revealing its efficiency and quieter operation compared to traditional rotors, with implications for low-noise aerial vehicles.

Contribution

It provides the first detailed aerodynamic and aeroacoustic analysis of the da Vinci aerial screw, comparing it to conventional rotors and highlighting its potential for low-noise flight.

Findings

42.2% lower power consumption than traditional rotors

72.3% lower acoustic intensity per lift

Suppressed blade-vortex interaction noise

Abstract

Leonardo da Vinci's aerial screw, conceived in the 15th century, represents one of the earliest conceptualizations of lift-generating rotary flight. Despite its historical significance, the aerodynamic and aeroacoustic performance of this rotor has received limited scientific attention. In this study, we employ direct numerical simulations to analyze the aerodynamic forces and acoustic emissions of a modernized da Vinci aerial screw design across a range of Reynolds numbers (2000, 4000, 8000, and 16000). These results are compared against those from a canonical two-bladed rotor producing similar lift. The aerial screw demonstrates 42.2% lower mechanical power consumption and 72.3% lower acoustic intensity per unit lift, primarily due to its larger wetted area and correspondingly lower rotational speed. Although the aerial screw exhibits a lower lift coefficient and much of its surface contributes minimally to lift generation, the net performance under iso-lift conditions highlights its efficiency and reduced noise signature. The continuous spiral geometry of the aerial screw also helps suppress blade-vortex interaction noise common in multi-bladed systems. These findings support previous scaling analyses and point toward unconventional rotor designs as viable options for low-noise aerial platforms.