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% lower power loading than the same rotor in isolation.
In comparison, the RRR configuration reduced power loading by 13.6% 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.