AERODYNAMIC INTERACTION EFFECTS OF TILTROTOR EVTOL AIRCRAFT

In light of recent advancements in electric aircraft systems tailored for eVTOL applications, there is a growing need for a better understanding of aerodynamic loads and their interactions for unconventional propulsion systems which must deliver both lift and thrust. Therefore, a wind tunnel model was specifically designed for investigating wing-propeller aerodynamic interactions of eVTOL aircraft, including vectored thrust mechanisms. The model encompasses capabilities for both time-averaged and time-resolved measurements of load and pressure data, and the facilities at the Technical University of Munich also enabled flow visualization with Particle Image Velocimetry (PIV). This paper offers load, pressure and flow visualization data for wing-propeller configurations, considering propeller tilt angles between 0◦ and 90◦ with 15 degree steps. It was found that Root Mean Square (RMS) values of forces measured at the propeller are lower for lower tilt angles with regard to the wing when comparing similar angles of inflow at the propeller plane. Power Spectral Densities (PSD) of total model forces show that the propeller rotation frequency and its harmonics are relevant, especially as tilt angle increased. PIV revealed significant variation in wake vortex structures depending on tilt angle.