Downwash/Outwash Investigation in Support of eVTOL Landing Operations

The analysis of rotor downwash and outwash (DWOW) for electric vertical takeoff and landing vehicles (eVTOLs) based on tools and experience from conventional helicopter designs was investigated in this study. eVTOL aircraft exhibit diverse rotor configurations compared to traditional helicopters and therefore pose unique challenges in landing area operations. Flow field simulation of an eVTOL configuration in hover and in proximity to the ground was employed for qualitative and quantitative analyses of the rotor wake, including the aerodynamic interactions of adjacent lift rotors and the ground surface. The viscous vortex particle method (VVPM) was investigated for the characterization of the eVTOL DWOW velocities and the development of flow velocity measurement arrangements for simulation validation.