Experimental and Numerical Studies on the Effect of Airflow Separation Suppression on Aerodynamic Performance of a Ducted Coaxial Propeller in Hovering

The ducted coaxial propeller (DCP) has great application value in eVTOL aircraft because of its high safety, compactness, and low noise. A numerical simulation method for the DCP is established using sliding mesh technique. was designed manufactured lift power test to verify method. characteristics airflow separation inside were studied, influence vortex restrain ring (VRR) on suppression augmentation duct analyzed. Results show that, when tip clearance ratio increases from 0.336% 1.342%, both total aerodynamic efficiency decrease by about 11.3%. mainly reflected formation vortex, straight, diffusion sections duct. Tip energy dissipation clogs inner wall duct, reducing effective diameter through Moreover, role weakened, wake contracted, which induced loss. By adding a VRR section, can be effectively suppressed, increase 5.1%.