| 摘要 |
An axial-flow fan having a high fan efficiency and high performance is provided by improving a fluid flow on the rear edge side of a blade tip without deteriorating the fluid flow on the front side of the blade tip, and reducing loss of horsepower without causing a large influence on loadings. The blade has a warped portion on the side surface of the blade tip on the rear edge side thereof, being formed by bending the blade tip toward upstream at angles between 5 to 30 degrees with a smooth filet R along a line C connecting a position along the blade tip at the chord length A to 1/5 A from the rear edge of the blade tip toward the front edge of the blade tip and a position along the radial length B of the blade at 1/2B to 1/10B from the rear edge of the blade tip. |
