| 摘要 |
PROBLEM TO BE SOLVED: To achieve a more adequate method for suppressing stall of an airfoil by flowing fluid through at least one section on the airfoil in the application of a rotary-wing aircraft. SOLUTION: An airfoil 10 moves through a fluid medium 24 using a front fringe 16 thereof in the head and a rear fringe 18 thereof at the back. When the medium 24 passes the airfoil 10, it is possible to suppress stall of the airfoil 10 by forcing the vibration on the medium 24 at several sections on a surface thereof, for example, the front fringe 16, the rear fringe 18, a position 26 on a top face 12 within one-fourth from the front fringe 16 in a chord 22, a position 28 which exceeds one-fourth, a position 30 on a bottom face 14 within one- fourth, and a position 32 which exceeds one-fourth. This forced vibration is generated by flowing fluid from the inside 20 to the medium 24 at, for example, positions 16, 18, 26, 28, 30, or 32. This stream may be a stream having a net amount of zero. At this time, forcing vibration is done at a frequency of which stall-hull ratio exceeds substantially 1 to modulate the force of the fluid in the frequency or amplitude. |
