摘要 |
A ducted fan for a VTOL vehicle includes a substantially cylindrical duct having an inlet at an upper end and an outlet at a lower end, a propulsion unit inside the duct, between the inlet and the outlet, and at least one group of control vanes located above the inlet a distance equal to at least one-quarter vane chord length, while a related method includes the steps of (a) shaping the inlet of the duct to have a diameter equal to or less than a diameter of the duct proximate the outlet, and (b) locating a first group of inlet vanes a distance above the inlet as a function of duct inlet diameter, and still another method creates side forces and rolling moments through the use of cambered vanes. |