TRANSITION DUCT FOR CENTRIFUGAL FAN

摘要

The present invention provides a curvilinear transition duct (10) for use with a centrifugal fan (40) that affords optimal fan efficiency without undue duct length. The duct comprises a top section (12) of generally concave planar shape when viewed from above and a bottom section (14). Side sections join the top and bottom sections to form a four sided structure having an inlet opening (20) at one side and an outlet opening at the other side (22). The top plate (12) is arranged to have a positive angle of expansion (DT) whilst the bottom plate (14) may be arranged to have a zero angle of expansion or a positive angle of expansion (DB) less than that of the top plate (12) such that the duct gradually diverges in the same direction as fan housing scroll development.