Numerical Investigation of Low-Noise Landing Conditions for Multirotor Urban Air Mobility Vehicle

Abstract

A preliminary investigation of the noise abatement landing approach for the multirotor urban air mobility (UAM) vehicle is carried out using the comprehensive multirotor noise assessment (CONA) framework. The key objectives are to identify the low-noise landing condition of multirotor UAM vehicles to reduce ground noise impact near the landing zone. The CONA framework, developed by our research team, has the capability of trajectory-based noise prediction for RPM-controlled multirotor configurations. It uses the parameterized Beddoes wake model with regression analysis to consider the aerodynamic interaction. The noise impact over a wide range of landing conditions is illustrated for the quadrotor UAM vehicle. Three landing conditions are highlighted: vertical descent, high-noise condition, and low-noise condition. The result shows that the low-noise condition avoids intense aerodynamic interaction and reduces the tip Mach number with a high flight path angle and forward speed. This condition can significantly reduce the area affected by UAM noise. In summary, the noise abatement landing approach has a significant noise reduction in the multirotor UAM vehicle, and the landing approach should be designed by considering landing conditions and UAM configurations.