Rotor/Airframe Aeroacoustic Prediction for eVTOL UAM Aircraft

A major innovative thrust in urban air mobility (UAM) is underway that will potentially transform how we travel by providing on-demand, affordable, quiet, and fast passenger-carrying operations in metropolitan areas using electric powered vertical take-off and landing (eVTOL) aircraft. To support this, it is propitious to enhance existing VTOL aircraft analysis and design tools as necessary and provide these enhanced tools to entrepreneurs attempting to design this new breed of aircraft. In this regard, work was performed to enhance an existing VTOL aircraft aeroacoustics analysis with additional modeling capabilities useful for comprehensive acoustic prediction of Distributed Electric Propulsion (DEP) aircraft noise. The goal is to develop software that will provide fast, accurate prediction of acoustic characteristics associated with DEP aircraft, including (1) noise generated by the simultaneous operation of multiple, variable RPM lifting and propelling rotors and props, (2) interacting rotor/prop/duct/airframe noise, including strut noise and prop/wing interaction noise, (3) broadband noise characteristic of eVTOL configurations, and (4) electric motor noise. This paper describes initial work toward these goals that was performed to enhance and validate a fast method for predicting rotor/airframe noise for combinations of rotor, props, struts, ducts and wings.