AXIAL FLOW FAN WITH AUXILIARY BLADES

摘要

An axial flow fan having auxiliary blades which includes a hub rotatably supported and driven by a drive source, a plurality of fan blades extending radially outwardly from the hub and at least one auxiliary blade projecting from an outer part on a suction and/or pressure surface of the fan blade and extending in the chord-length direction in such a manner that the leading region of the auxiliary blade is located nearer to the central axis of the fan than the trailing region thereof. A supplementary angle theta 0 of an angle formed between a chord line connecting to a leading edge and a trailing edge of the outer auxiliary blade and a reference line decided by the shape or operation of the fan blade has the relation; 5 DEG