Counter-rotating axial flow fan

摘要

Provided here is a counter-rotating axial flow fan with improved air flow-static pressure characteristics and reduced power consumption and noise compared to the related art. A plurality of struts are disposed to be stationary between a front impeller and a rear impeller in an air channel. A plurality of front blades are each formed of a swept-back blade, and a plurality of rear blades are each formed of a forward-swept blade.

主权项

1. A counter-rotating axial flow fan comprising:
a casing including an air channel having a suction port at one axial end of the air channel and a discharge port at the other axial end of the air channel; a front impeller including a plurality of front blades and configured to rotate in the air channel; a rear impeller including a plurality of rear blades and configured to rotate in the air channel in a direction opposite to a direction of rotation of the front impeller; and a plurality of struts disposed to be stationary between the front impeller and the rear impeller in the air channel, wherein: the plurality of front blades are each formed of a swept-back blade, and the plurality of rear blades are each formed of a forward-swept blade, and defining the outside diameter of the front blades as Rf, the minimum clearance Cf between the front blades and the struts is determined as a value in the range of Rf/4>Cf>Rf/6.