Fan system

1. An inline centrifugal mixed flow fan system, comprising:

a wheel assembly disposed within an outer housing and comprising a hub cone, a plurality of fan blades directly coupled to and extending radially outward from the hub cone, and a shroud directly coupled to and at least partially radially surrounding the plurality of fan blades, wherein the wheel assembly is configured to receive an air flow at an inlet axial end of the outer housing axially upstream of the wheel assembly, and to redirect the air flow axially downstream relative to a central longitudinal axis, circumferentially about the central longitudinal axis, and radially outward from the central longitudinal axis, wherein a ratio of an axial length of the hub cone relative to an outer diameter of the hub cone is within a range of approximately 0.31 to approximately 0.44, and wherein a ratio of an axial length of the shroud relative to an outer diameter of the shroud is within a range of approximately 0.16 to approximately 0.30.

2. The inline centrifugal mixed flow fan system of claim 1 , comprising a bearing tunnel radially disposed within the outer housing, wherein the bearing tunnel is disposed axially downstream of the wheel assembly.

3. The inline centrifugal mixed flow fan system of claim 2 , comprising a plurality of guide vanes directly coupled to and extending radially outward from the bearing tunnel, wherein the plurality of guide vanes are configured to counteract circumferential movement of the air flow and to direct the air flow to a discharge axial end of the outer housing.

4. The inline centrifugal mixed flow fan system of claim 2 , comprising:

a drive shaft disposed within the bearing tunnel and configured to cause rotation of the wheel assembly; and

one or more bearings disposed within the bearing tunnel and configured to support the drive shaft.

5. The inline centrifugal mixed flow fan system of claim 2 , wherein an outer diameter of the bearing tunnel is substantially similar to the outer diameter of the hub cone.

6. The inline centrifugal mixed flow fan system of claim 1 , comprising an inlet venturi fixedly coupled to the outer housing at the inlet axial end of the outer housing.

7. The inline centrifugal mixed flow fan system of claim 6 , wherein the inlet venturi comprises a plurality of discrete inlet venturi segments disposed adjacent each other axially along the central longitudinal axis.

8. The inline centrifugal mixed flow fan system of claim 6 , wherein the shroud comprises a cylindrical lip at an axial end of the shroud adjacent the inlet venturi, wherein the cylindrical lip is configured to radially surround a portion of the inlet venturi.

9. The inline centrifugal mixed flow fan system of claim 6 , wherein the hub cone comprises a plurality of discrete hub cone segments disposed adjacent each other axially along the central longitudinal axis.

10. The inline centrifugal mixed flow fan system of claim 1 , wherein an angle, in a plane perpendicular to the central longitudinal axis, between a line along the hub cone at an intersection point of the hub cone and a leading edge of a fan blade of the plurality of fan blades relative to a line indicative of a direction of rotation of the hub cone at the intersection point of the hub cone and the leading edge of the fan blade is within a range of approximately 20 degrees to approximately 27 degrees.

11. The inline centrifugal mixed flow fan system of claim 1 , wherein an angle, in a plane perpendicular to the central longitudinal axis, between a line along the hub cone at an intersection point of the hub cone and a trailing edge of a fan blade of the plurality of fan blades relative to a line indicative of a direction of rotation of the hub cone at the intersection point of the hub cone and the trailing edge of the fan blade is within a range of approximately 47 degrees to approximately 54 degrees.

12. The inline centrifugal mixed flow fan system of claim 1 , wherein an angle, in a plane perpendicular to the central longitudinal axis, between a line along the shroud at an intersection point of the shroud and a leading edge of a fan blade of the plurality of fan blades relative to a line indicative of a direction of rotation of the shroud at the intersection point of the shroud and the leading edge of the fan blade is within a range of approximately 10 degrees to approximately 17 degrees.

13. The inline centrifugal mixed flow fan system of claim 1 , wherein an angle, in a plane perpendicular to the central longitudinal axis, between a line along the shroud at an intersection point of the shroud and a trailing edge of a fan blade of the plurality of fan blades relative to a line indicative of a direction of rotation of the shroud at the intersection point of the shroud and the trailing edge of the fan blade is within a range of approximately 11 degrees to approximately 18 degrees.

14. The inline centrifugal mixed flow fan system of claim 1 , wherein an angle, relative to a line parallel to the central longitudinal axis, of a leading edge of a fan blade of the plurality of fan blades is within a range of approximately 61 degrees to approximately 69 degrees.

15. The inline centrifugal mixed flow fan system of claim 1 , wherein an angle, relative to a line parallel to the central longitudinal axis, of a trailing edge of a fan blade of the plurality of fan blades is within a range of approximately 50 degrees to approximately 58 degrees.

16. An inline centrifugal mixed flow fan system, comprising:

a wheel assembly disposed within an outer housing and comprising a hub cone, a plurality of fan blades directly coupled to and extending radially outward from the hub cone, and a shroud directly coupled to and at least partially radially surrounding the plurality of fan blades, wherein the wheel assembly is configured to receive an air flow at an inlet axial end of the outer housing axially upstream of the wheel assembly, and to redirect the air flow axially downstream relative to a central longitudinal axis, circumferentially about the central longitudinal axis, and radially outward from the central longitudinal axis, wherein a ratio of an axial length of the shroud relative to an outer diameter of the shroud is within a range of approximately 0.16 to approximately 0.30, and wherein an angle, relative to a line parallel to the central longitudinal axis, of a trailing edge of a fan blade of the plurality of fan blades is within a range of approximately 50 degrees to approximately 58 degrees.

17. The inline centrifugal mixed flow fan system of claim 16 , wherein an angle, in a plane perpendicular to the central longitudinal axis, between a line along the hub cone at an intersection point of the hub cone and a leading edge of a fan blade of the plurality of fan blades relative to a line indicative of a direction of rotation of the hub cone at the intersection point of the hub cone and the leading edge of the fan blade is within a range of approximately 20 degrees to approximately 27 degrees.

18. The inline centrifugal mixed flow fan system of claim 16 , wherein an angle, in a plane perpendicular to the central longitudinal axis, between a line along the hub cone at an intersection point of the hub cone and a trailing edge of a fan blade of the plurality of fan blades relative to a line indicative of a direction of rotation of the hub cone at the intersection point of the hub cone and the trailing edge of the fan blade is within a range of approximately 47 degrees to approximately 54 degrees.

19. The inline centrifugal mixed flow fan system of claim 16 , wherein an angle, in a plane perpendicular to the central longitudinal axis, between a line along the shroud at an intersection point of the shroud and a leading edge of a fan blade of the plurality of fan blades relative to a line indicative of a direction of rotation of the shroud at the intersection point of the shroud and the leading edge of the fan blade is within a range of approximately 10 degrees to approximately 17 degrees.

20. The inline centrifugal mixed flow fan system of claim 16 , wherein an angle, in a plane perpendicular to the central longitudinal axis, between a line along the shroud at an intersection point of the shroud and a trailing edge of a fan blade of the plurality of fan blades relative to a line indicative of a direction of rotation of the shroud at the intersection point of the shroud and the trailing edge of the fan blade is within a range of approximately 11 degrees to approximately 18 degrees.

21. The inline centrifugal mixed flow fan system of claim 16 , wherein an angle, relative to the line parallel to the central longitudinal axis, of a leading edge of a fan blade of the plurality of fan blades is within a range of approximately 61 degrees to approximately 69 degrees.

22. An inline centrifugal mixed flow fan system, comprising:

a wheel assembly disposed within an outer housing and comprising a hub cone, a plurality of fan blades directly coupled to and extending radially outward from the hub cone, and a shroud directly coupled to and at least partially radially surrounding the plurality of fan blades, wherein the wheel assembly is configured to receive an air flow at an inlet axial end of the outer housing axially upstream of the wheel assembly, and to redirect the air flow axially downstream relative to a central longitudinal axis, circumferentially about the central longitudinal axis, and radially outward from the central longitudinal axis, wherein a ratio of an axial length of the hub cone relative to an outer diameter of the hub cone is within a range of approximately 0.31 to approximately 0.44, and wherein an angle, in a plane perpendicular to the central longitudinal axis, between a line along the hub cone at an intersection point of the hub cone and a leading edge of a fan blade of the plurality of fan blades relative to a line indicative of a direction of rotation of the hub cone at the intersection point of the hub cone and the leading edge of the fan blade is within a range of approximately 20 degrees to approximately 27 degrees.

23. An inline centrifugal mixed flow fan system, comprising:

a wheel assembly disposed within an outer housing and comprising a hub cone, a plurality of fan blades directly coupled to and extending radially outward from the hub cone, and a shroud directly coupled to and at least partially radially surrounding the plurality of fan blades, wherein the wheel assembly is configured to receive an air flow at an inlet axial end of the outer housing axially upstream of the wheel assembly, and to redirect the air flow axially downstream relative to a central longitudinal axis, circumferentially about the central longitudinal axis, and radially outward from the central longitudinal axis, wherein a ratio of an axial length of the hub cone relative to an outer diameter of the hub cone is within a range of approximately 0.31 to approximately 0.44, and wherein an angle, in a plane perpendicular to the central longitudinal axis, between a line along the hub cone at an intersection point of the hub cone and a trailing edge of a fan blade of the plurality of fan blades relative to a line indicative of a direction of rotation of the hub cone at the intersection point of the hub cone and the trailing edge of the fan blade is within a range of approximately 47 degrees to approximately 54 degrees.

24. An inline centrifugal mixed flow fan system, comprising:

a wheel assembly disposed within an outer housing and comprising a hub cone, a plurality of fan blades directly coupled to and extending radially outward from the hub cone, and a shroud directly coupled to and at least partially radially surrounding the plurality of fan blades, wherein the wheel assembly is configured to receive an air flow at an inlet axial end of the outer housing axially upstream of the wheel assembly, and to redirect the air flow axially downstream relative to a central longitudinal axis, circumferentially about the central longitudinal axis, and radially outward from the central longitudinal axis, wherein a ratio of an axial length of the hub cone relative to an outer diameter of the hub cone is within a range of approximately 0.31 to approximately 0.44, and wherein an angle, in a plane perpendicular to the central longitudinal axis, between a line along the shroud at an intersection point of the shroud and a leading edge of a fan blade of the plurality of fan blades relative to a line indicative of a direction of rotation of the shroud at the intersection point of the shroud and the leading edge of the fan blade is within a range of approximately 10 degrees to approximately 17 degrees.

25. An inline centrifugal mixed flow fan system, comprising:

a wheel assembly disposed within an outer housing and comprising a hub cone, a plurality of fan blades directly coupled to and extending radially outward from the hub cone, and a shroud directly coupled to and at least partially radially surrounding the plurality of fan blades, wherein the wheel assembly is configured to receive an air flow at an inlet axial end of the outer housing axially upstream of the wheel assembly, and to redirect the air flow axially downstream relative to a central longitudinal axis, circumferentially about the central longitudinal axis, and radially outward from the central longitudinal axis, wherein a ratio of an axial length of the hub cone relative to an outer diameter of the hub cone is within a range of approximately 0.31 to approximately 0.44, and wherein an angle, in a plane perpendicular to the central longitudinal axis, between a line along the shroud at an intersection point of the shroud and a trailing edge of a fan blade of the plurality of fan blades relative to a line indicative of a direction of rotation of the shroud at the intersection point of the shroud and the trailing edge of the fan blade is within a range of approximately 11 degrees to approximately 18 degrees.

26. An inline centrifugal mixed flow fan system, comprising:

a wheel assembly disposed within an outer housing and comprising a hub cone, a plurality of fan blades directly coupled to and extending radially outward from the hub cone, and a shroud directly coupled to and at least partially radially surrounding the plurality of fan blades, wherein the wheel assembly is configured to receive an air flow at an inlet axial end of the outer housing axially upstream of the wheel assembly, and to redirect the air flow axially downstream relative to a central longitudinal axis, circumferentially about the central longitudinal axis, and radially outward from the central longitudinal axis, wherein a ratio of an axial length of the hub cone relative to an outer diameter of the hub cone is within a range of approximately 0.31 to approximately 0.44, and wherein an angle, relative to a line parallel to the central longitudinal axis, of a leading edge of a fan blade of the plurality of fan blades is within a range of approximately 61 degrees to approximately 69 degrees.

27. An inline centrifugal mixed flow fan system, comprising:

a wheel assembly disposed within an outer housing and comprising a hub cone, a plurality of fan blades directly coupled to and extending radially outward from the hub cone, and a shroud directly coupled to and at least partially radially surrounding the plurality of fan blades, wherein the wheel assembly is configured to receive an air flow at an inlet axial end of the outer housing axially upstream of the wheel assembly, and to redirect the air flow axially downstream relative to a central longitudinal axis, circumferentially about the central longitudinal axis, and radially outward from the central longitudinal axis, wherein a ratio of an axial length of the hub cone relative to an outer diameter of the hub cone is within a range of approximately 0.31 to approximately 0.44, and wherein an angle, relative to a line parallel to the central longitudinal axis, of a trailing edge of a fan blade of the plurality of fan blades is within a range of approximately 50 degrees to approximately 58 degrees.

28. An inline centrifugal mixed flow fan system, comprising:

a wheel assembly disposed within an outer housing and comprising a hub cone, a plurality of fan blades directly coupled to and extending radially outward from the hub cone, and a shroud directly coupled to and at least partially radially surrounding the plurality of fan blades, wherein the wheel assembly is configured to receive an air flow at an inlet axial end of the outer housing axially upstream of the wheel assembly, and to redirect the air flow axially downstream relative to a central longitudinal axis, circumferentially about the central longitudinal axis, and radially outward from the central longitudinal axis, wherein a ratio of an axial length of the shroud relative to an outer diameter of the shroud is within a range of approximately 0.16 to approximately 0.30, and wherein an angle, in a plane perpendicular to the central longitudinal axis, between a line along the hub cone at an intersection point of the hub cone and a leading edge of a fan blade of the plurality of fan blades relative to a line indicative of a direction of rotation of the hub cone at the intersection point of the hub cone and the leading edge of the fan blade is within a range of approximately 20 degrees to approximately 27 degrees.

29. An inline centrifugal mixed flow fan system, comprising:

a wheel assembly disposed within an outer housing and comprising a hub cone, a plurality of fan blades directly coupled to and extending radially outward from the hub cone, and a shroud directly coupled to and at least partially radially surrounding the plurality of fan blades, wherein the wheel assembly is configured to receive an air flow at an inlet axial end of the outer housing axially upstream of the wheel assembly, and to redirect the air flow axially downstream relative to a central longitudinal axis, circumferentially about the central longitudinal axis, and radially outward from the central longitudinal axis, wherein a ratio of an axial length of the shroud relative to an outer diameter of the shroud is within a range of approximately 0.16 to approximately 0.30, and wherein an angle, in a plane perpendicular to the central longitudinal axis, between a line along the hub cone at an intersection point of the hub cone and a trailing edge of a fan blade of the plurality of fan blades relative to a line indicative of a direction of rotation of the hub cone at the intersection point of the hub cone and the trailing edge of the fan blade is within a range of approximately 47 degrees to approximately 54 degrees.

30. An inline centrifugal mixed flow fan system, comprising:

a wheel assembly disposed within an outer housing and comprising a hub cone, a plurality of fan blades directly coupled to and extending radially outward from the hub cone, and a shroud directly coupled to and at least partially radially surrounding the plurality of fan blades, wherein the wheel assembly is configured to receive an air flow at an inlet axial end of the outer housing axially upstream of the wheel assembly, and to redirect the air flow axially downstream relative to a central longitudinal axis, circumferentially about the central longitudinal axis, and radially outward from the central longitudinal axis, wherein a ratio of an axial length of the shroud relative to an outer diameter of the shroud is within a range of approximately 0.16 to approximately 0.30, and wherein an angle, in a plane perpendicular to the central longitudinal axis, between a line along the shroud at an intersection point of the shroud and a leading edge of a fan blade of the plurality of fan blades relative to a line indicative of a direction of rotation of the shroud at the intersection point of the shroud and the leading edge of the fan blade is within a range of approximately 10 degrees to approximately 17 degrees.

31. An inline centrifugal mixed flow fan system, comprising:

a wheel assembly disposed within an outer housing and comprising a hub cone, a plurality of fan blades directly coupled to and extending radially outward from the hub cone, and a shroud directly coupled to and at least partially radially surrounding the plurality of fan blades, wherein the wheel assembly is configured to receive an air flow at an inlet axial end of the outer housing axially upstream of the wheel assembly, and to redirect the air flow axially downstream relative to a central longitudinal axis, circumferentially about the central longitudinal axis, and radially outward from the central longitudinal axis, wherein a ratio of an axial length of the shroud relative to an outer diameter of the shroud is within a range of approximately 0.16 to approximately 0.30, and wherein an angle, in a plane perpendicular to the central longitudinal axis, between a line along the shroud at an intersection point of the shroud and a trailing edge of a fan blade of the plurality of fan blades relative to a line indicative of a direction of rotation of the shroud at the intersection point of the shroud and the trailing edge of the fan blade is within a range of approximately 11 degrees to approximately 18 degrees.

32. An inline centrifugal mixed flow fan system, comprising:

a wheel assembly disposed within an outer housing and comprising a hub cone, a plurality of fan blades directly coupled to and extending radially outward from the hub cone, and a shroud directly coupled to and at least partially radially surrounding the plurality of fan blades, wherein the wheel assembly is configured to receive an air flow at an inlet axial end of the outer housing axially upstream of the wheel assembly, and to redirect the air flow axially downstream relative to a central longitudinal axis, circumferentially about the central longitudinal axis, and radially outward from the central longitudinal axis, wherein a ratio of an axial length of the shroud relative to an outer diameter of the shroud is within a range of approximately 0.16 to approximately 0.30, and wherein an angle, relative to a line parallel to the central longitudinal axis, of a leading edge of a fan blade of the plurality of fan blades is within a range of approximately 61 degrees to approximately 69 degrees.