Abstract
Air-separators are one of effective methods to suppress stall phenomena of axial flow fans. In the present study, numerical investigations are carried out to clarify the stall suppression mechanisms of the air-separator using an axial flow fan with
and without the air-separator which are examined experimentally by Yamaguchi et al. The comparisons between numerical
and experimental results show reasonable agreements. The results show that a backflow region around the rotor tip is
removed at the low flow rate and that the blade loading around the blade tip is increased by the air-separator. Consequently
the pressure performance at the low flow rate is improved significantly. Additionally, influences of flow rate through the
air-separator and air-separator geometries are also examined to clarify the air-separator effects.
