PROPULSION DEVICE HAVING UNDUCTED COUNTER-ROTATING AND COAXIAL ROTORS

摘要

A propulsion device including an unducted upstream propeller and a counter-rotating and coaxial downstream propeller. At least one blade of the upstream propeller is configured to generate a corotating secondary vortex for acting upstream of the downstream propeller to destabilize a blade tip vortex of the same at least one blade.