Numerical Analysis UAV Propeller Noise Based on the Joby S4 eVTOL

With the rapid development of the concept of Urban Air Mobility (UAM), electric vertical take-off and landing (eVTOL) aircraft have shown great potential in low-altitude transportation. However, noise has become a key factor restricting their application in urban environments. This paper focuses on the optimization of a Joby S4-based eVTOL configuration and conducts a numerical analysis of its propeller noise characteristics. First, a three-dimensional simulation model is established based on the geometric features of the Joby S4 propeller, and the unsteady Reynolds-Averaged Navier–Stokes (URANS) method is applied to obtain the instantaneous pressure distribution on the blade surface. Then, the Ffowcs Williams–Hawkings (FW-H) equation is used to compute the far-field sound pressure level. The results show that propeller noise is mainly dominated by tip-vortex noise and blade-passing-frequency (BPF) noise. This study provides theoretical and technical support for the low-noise propeller design and urban operational noise control of eVTOL-type unmanned aerial vehicles.