도심 환경 착륙 시 회전익 비행체의 공력 소음 예측 연구

Abstract

Urban Air Mobility (UAM) has been developed as a new transportation system and is expected to operate in congested urban environments near vertiports and surrounding buildings. These environments can produce unsteady aerodynamic interference phenomena, including ground and obstacle effects, which may increase flight instability and noise levels. In this study, we investigated the ground and obstacle effects on the aerodynamic performance and acoustic characteristics of a helicopter model using the vortex-based rotorcraft analysis code VALOR (Vortex-based Aerodynamic simuLation cOde for Rotorcraft) and an acoustic analogy based on the Farassat-1A formula. The simulation results indicate that the ground and obstacle effects generate unsteady aerodynamic loads acting on the rotor blades. In addition, strong unsteady aerodynamic loads lead to a high overall sound pressure level (OASPL) in the noise hemisphere. Finally, the parametric study showed that the highest OASPL occurred when the aircraft was located near or above the obstacle.