Fan wheel systems and methods

A fan wheel, comprising:

• a hub comprising a passage extending along an axis and configured to receive a shaft;
• a shroud disposed about the hub and comprising an inner surface, wherein the inner surface extends from a first end portion of the shroud to a second end portion of the shroud, and wherein the inner surface comprises a diverging section that diverges radially from the axis along a direction extending from the first end portion toward the second end portion;
• and
• a fan blade comprising a body portion and a plurality of mounting tabs extending from the body portion, wherein the plurality of mounting tabs is coupled to the diverging section of the inner surface via mechanical fasteners.

A fan wheel for a mixed flow fan system, comprising:

• a hub configured to rotate about an axis of the mixed flow fan system, the hub comprising:
• a first hub plate having a first mounting surface positioned at a first location along the axis;
• and
• a second hub plate offset from the first hub plate along the axis and having a second mounting surface positioned at a second location along the axis;
• and
• a fan blade comprising a first mounting tab and a second mounting tab, wherein the first mounting tab is mounted to the first mounting surface, and the second mounting tab is mounted to the second mounting surface.