Clearance flow control for mixed-flow fan

Abstract

Described herein is a mixed-flow fan assembly. The assembly comprises an impeller comprising a plurality of blades extending from a rotatable hub, and a shroud extending circumferentially around the impeller, wherein the shroud is secured to the plurality of blades, a casing with a bellmouth disposed circumferentially around the shroud, defining a cavity between the casing and the shroud, with flow control clearance gaps at a downstream end and an upstream end of the casing. The assembly further comprises one or more first circular ribs extending axially from the shroud within the cavity and substantially parallel to a rotational axis of the impeller, and a plurality of de-swirl vanes configured at predefined positions on an inner surface of the bellmouth.

Dependencies are inferred from the claim text.