Abstract: The present invention provides a centrifugal fan assembly including a housing and a centrifugal fan. The centrifugal fan includes main blades, each including a suction surface, a pressure surface, a leading edge, and a trailing edge. The centrifugal fan also includes secondary blades, each including a suction surface and a pressure surface. Each main blade defines a mean line between the suction surface and the pressure surface, and a nose-tail line intersecting the main blade mean line at the leading edge and the trailing edge. Each secondary blade defines a mean line between the suction surface and the pressure surface. A portion of the secondary blade mean line is substantially parallel to the main blade mean line when superimposed, and a portion of the superimposed secondary blade mean line deviates from the main blade mean line in a direction toward the main blade nose-tail line.

Abstract: The present invention provides a centrifugal fan assembly including a housing and a centrifugal fan. The centrifugal fan includes main blades, each including a suction surface, a pressure surface, a leading edge, and a trailing edge. The centrifugal fan also includes secondary blades, each including a suction surface and a pressure surface. Each main blade defines a mean line between the suction surface and the pressure surface, and a nose-tail line intersecting the main blade mean line at the leading edge and the trailing edge. Each secondary blade defines a mean line between the suction surface and the pressure surface. A portion of the secondary blade mean line is substantially parallel to the main blade mean line when superimposed, and a portion of the superimposed secondary blade mean line deviates from the main blade mean line in a direction toward the main blade nose-tail line.