CPC F04D 29/384 (2013.01) [F04D 29/52 (2013.01)] | 38 Claims |
1. A fan arrangement for a duct, the fan arrangement including a housing having an inlet and an outlet adapted to communicate air with the duct and an axially rotatably driven impeller supported within the housing between the inlet and the outlet, the impeller including a hub carrying a plurality of blades that span in a radial direction outwardly of the hub, the plurality of blades being shaped to urge air between the inlet and the outlet,
wherein the plurality of blades have a tip solidity ratio in the range of about 0.8 to 1.55, and
wherein each of the plurality of blades has a twist angle between a root and a tip thereof in the range of about 15 to 30 degrees and a substantially constant thickness across a chord thereof, and
wherein, when viewed in front plan form, leading edges and trailing edges of adjacent ones of the plurality of blades are parallel in a radial direction.
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