Performance Analysis of Distributed Propellers: Efficiency and Noise Trade-Offs in Full-Electric Regional Aircraft

Distributed propulsion systems, characterized by multiple propellers, represent a promising approach for full-electric aircrafts, offering several advantages but also introducing technical challenges. The main objective of this paper is to quantify how the propeller performance and noise emissions of an eight-propeller full-electric aircraft configuration compare to that of a conventional fuel-based turboprop. In both cases, the key parameters driving the trade-off between noise emissions and aerodynamic performances are analysed as well as the benefits of each configuration. The propeller noise emissions are analysed in terms of the perceived noise emissions at the three certification points: approach, take-off, and flyover. Optimizations are performed as a function of blade count to investigate the performance and noise trends for different propeller configurations. The results show a promising performance for the battery-electric aircraft with distributed propulsion, achieving a propeller efficiency between 83% and 88% in cruise without incurring a major noise penalty compared to the reference turboprop aircraft, despite the large increase in aircraft size and weight.