Axial-flow fan

Abstract

Abstract PURPOSE:To lower the noise level of an axial-flow fan, by reducing the relative speed of fluid flow near the top of a runner by disposing inlet guide vanes for imparting prewhirl in the direction of rotation of the runner on the upstream side of the top of runner blades. CONSTITUTION:Inlet guide vanes 5 for reducing the relative speed of fluid flow to the cascade of a runner 3 are disposed in the manner of facing the top of the runner 3 on its upstream side. The axial speed V' of fluid flow on the upstream side of the inlet guide vanes 5 is turned in the direction of rotation of the runner 3 by the inlet guide vanes 5, so that fluid is discharged in the direction shown by C'1 in the drawing. On the other hand, since the runner 3 is turned at a circumferential speed (u), the fluid flow C'1 is introduced into the runner 3 in the direction of W'1 and discharged therefrom in the direction of W'2. Similarly, the absolute speed in the direction of W'2 becomes C'2, so that the noise level is lowered.

Inventors

• 👤 Yuki Furuyama
• 👤 古山　雪

Bibliographic Details