| 摘要 |
A fan assembly (10) comprising:
a shroud (12) having a through opening (14), around which the shroud defines an air conveying ring (17),
a motor-fan assembly (20) which includes an axial fan (22) rotatable with respect to the support about an axis of rotation (X), and
a noise-reducing annular structure (34; 134), having
- a plurality of projections (36; 137) which are arranged in succession in a circumferential direction and extend radially towards the axis of rotation (X) of the fan, each projection having a face (38; 138) which is directed towards the axis of rotation and is substantially parallel thereto, and
- a plurality of portions (43; 136, 144) radially recessed towards the air conveying ring (17). Each of the recessed portions has a face (44; 143, 144) which is directed towards the axis of rotation (X) of the fan and the profile of which in the axial direction is generally curvilinear and not parallel to the axis of rotation. |
