Computational Analysis of Rotor-Blown-Wing for eVTOL Applications

This study examines the performance of a rotor-blown-wing in hover and forward flight conditions. Flow solutions were generated using Helios, with a Detached Eddy Simulation (DES) model. The configuration is based on one set of rotors/wing of a quadrotor bi-plane tail-sitter aircraft. Simulations were conducted to assess the effect of varying angle of attack, rotor RPM, and rotor diameter. Two configurations were examined, the RBW baseline with two 60.96 cm diameter rotors, and the RRR configuration with four 30.48 cm diameter rotors. The smaller rotors were analyzed at the RPM corresponding to producing half the thrust of the RBW baseline rotor. The presence of the wing in hover resulted in the RBW baseline rotor operating at 1.9 percent lower power loading than the same rotor in isolation. In comparison, the RRR configuration reduced power loading by 13.6 percent compared to the isolated rotor. In forward flight (airplane mode), increasing angle of attack was shown to increase thrust produced on the downstroke side of the rotor. Furthermore, the presence of the wing increases the thrust produced on the bottom half of the disk. Both the blown-wings increase the L/D ratio from 3.2 for the isolated wing to 3.6 and 4.3 for the RBW baseline and RRR configurations respectively.