US20060093476A1

US20060093476A1 - Fan stator

Info

Publication number: US20060093476A1
Application number: US10/976,634
Authority: US
Inventors: Gavin Stanley; Ketan Shah; Ben Broili
Original assignee: Individual
Current assignee: Intel Corp
Priority date: 2004-10-29
Filing date: 2004-10-29
Publication date: 2006-05-04
Also published as: TWI312267B; TW200628059A; WO2006050285A1; DE112005002393T5; CN101044324B; CN101044324A

Abstract

According to some embodiments, an apparatus includes a housing, a hub, and a plurality of airfoils, each of the plurality of airfoils having a leading edge, a trailing edge, a first end, and a second end, wherein the first end of each of the plurality of airfoils is fixedly coupled to the hub and wherein the second end of each of the plurality of airfoils is fixedly coupled to the housing.

Description

BACKGROUND

Electronic components may generate heat in order to dissipate received power. The heat may damage or otherwise impair the functionality of such components. Various cooling systems have been employed to cool power-dissipating components, which may include processors, chipsets, voltage regulator components, and other components. Some cooling systems utilize a fan to evacuate heated air from a chassis including the power-dissipating components. Other cooling systems generate airflow using a fan and direct the airflow toward the power-dissipating components to provide cooling thereof

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a representative cutaway side view of a system according to some embodiments.
FIG. 2 is a perspective front (inlet) exploded view of a system according to some embodiments.
FIG. 3 is a perspective front (inlet) view of a system according to some embodiments.
FIG. 4 is a perspective rear (outlet) view of a system according to some embodiments.
FIG. 5 is a graph illustrating improvement in a system operating point according to some embodiments.
FIG. 6 is a diagram illustrating air velocity vector conversion according to some embodiments.
FIG. 7 is a perspective front (inlet) view of a thermal module according to some embodiments.
FIG. 8 is a perspective view of a system according to some embodiments.

DETAILED DESCRIPTION

FIGS. 1 through 4 show various views of a cooling system. In particular, FIG. 1 is a representative cutaway side view, FIG. 2 is an exploded perspective view, FIG. 3 is a front (inlet) perspective view, and FIG. 4 is a rear (outlet) perspective view of system 1 according to some embodiments. System 1 may comprise a system to cool devices by directing air thereto. System 1 may be used in conjunction with any suitable application, including but not limited to cooling electronic components housed in a chassis.
System 1 includes housing 10 and hub 20. A plurality of stator vanes 30 are coupled to housing 10 and hub 20. According to some embodiments, each of stator vanes 30 is an airfoil comprising a leading edge, a trailing edge, a first end and a second end. The first end of each airfoil is fixedly coupled to hub 20 and the second end is fixedly coupled to housing 10.
Housing 10, hub 20 and vanes 30 may be composed of any materials suitable for their intended use, including but not limited to plastics, resins, polymers, and metals. Physical dimensions of housing 10, hub 20 and vanes 30 may also vary according to intended uses and/or specifications with which system 1 is intended to comply. Housing 10, hub 20 and vanes 30 comprise a single integral unit according to some embodiments. Such a unit may be manufactured using injection molding techniques.
Fan 40 is coupled to hub 20 according to some embodiments. Motor 60 may be disposed within fan 40 and supported by hub 20 as shown. Motor 60 rotates blades 50 of fan 40 to deliver air to the leading edges of vanes 30. As shown in FIG. 1, input air 70 at pressure P₀is received and accelerated due to the rotation of blades 50. The accelerated air exhibits static pressure P₁includes a tangential velocity vector, an axial velocity vector, and a radial velocity vector that depend at least upon the design of fan 40, the speed of rotation and the location at which the accelerated air exits fan blades 50.
Vanes 30 receive the accelerated air. According to some embodiments, vanes 30 increase the static pressure of the air from P₁to P₂for a given axial velocity from leading edges of vanes 30 to trailing edges of vanes 30. The air exiting the trailing edges of vanes 30 is depicted in FIG. 1 as air 80.
For a particular fan speed, the flow and/or pressure of air 80 may be greater than would be provided by fan 40 in the absence of vanes 30. FIG. 5 depicts, for a given enclosure, operating point 0 ₁of a system consisting only of fan 40 and operating point 0 ₂of system 1. As shown, operating point 0 ₂is associated with a greater flow and a greater static pressure than operating point 0 ₁. System 1 may thereby cool downstream components more effectively than fan 40 alone.
The leading edges of vanes 30 receive the accelerated air from fan 40. In some embodiments, the leading edge of at least one of vanes 30 defines a first curve and the trailing edge of the blade defines a second curve. Examples of the first curve and the second curve are circumscribed by dotted line 31 of FIG. 2 and dotted line 32 of FIG. 4, respectively. The curves may reduce a radial velocity vector and increase an inlet-to-outlet static pressure of the received air. According to some embodiments, the first curve of at least one of vanes 30 is disposed perpendicular at a given radius to the trailing edge of at least one of fan blades 50 at the given radius. This latter arrangement may reduce a total area of interaction between the vanes and the blades at any given point in time, thereby creating less acoustic noise than alternative arrangements.
As mentioned above, vanes 30 may comprise airfoils according to some embodiments. If the accelerated air from fan 40 encounters the leading edge of a vane 30 at an appropriate angle of attack, the airfoil shape may produce lift that assists in converting at least some of the tangential velocity of the received air to pressure. In some embodiments, the blades comply with National Advisory Committee for Aeronautics (NACA) Four-Digit Series airfoil geometries 93xx, 94xx, 83xx, or 84xx. Examples of such geometries include airfoil geometries 9304, 9404, 8304, or 8404. According to these embodiments, the vanes are defined by a maximum camber of 8% or more of a length of the vanes.
FIG. 6 illustrates the transformation of the received air velocity vectors due at least in part to the above-described curvature and airfoil shape of vanes 30. Blade 50 of fan 40 is shown in cross-section. Blade 50 receives air 70 at pressure P₀and rotates to generate air at a greater pressure P₁. The generated air is represented by vector diagram 90. As shown, the velocity vector V_total0of the air includes an axial component V_axial0, a tangential (or “swirl”) component V_tangential0, and a radial component V_radial0perpendicular to the page.
The accelerated air then encounters vane 30, also shown in cross-section. Air 80 exiting from a trailing edge of vane 30 exhibits an increase in static pressure from P₁to P₂, while the axial velocity component V_axial1remains substantially equal to axial component V_axial0. However, magnitudes of both tangential velocity component V_tangential1and radial component V_radial0are less than respective components V_tangential0and V_radial0of the air received by the leading edge of vane 30.
The angle at which the accelerated air impinges on the leading edges of vanes 30 may decrease with distance from hub 20. One or more of vanes 30 may therefore be “twisted” such that this “vane angle” varies with radius. When such a twist is employed, the first end of one of the one or more vanes 30 is not coplanar with the second end of the one or more vanes 30. The vane angle is measured by connecting a line between the leading edge and the trailing edge of the blade (known as the chord), where that line then intersects with a horizontal plane when the hub 15 is disposed horizontally.
The vane angle may increase as a function of radius. In some embodiments, the vane angle of at least one of vanes 30 is 55 degrees at hub 20 and 75 degrees at housing 10. Some embodiments may provide a vane angle of at least one of vanes 30 that is 43 degrees at hub 20 and 73 degrees at housing 10.
According to some embodiments, the number of blades 50 is N and the number of vanes 30 is not an integer multiple of N. Such an arrangement may provide increased acoustic interference and thereby reduce the operational noise of system 1 in comparison to other arrangements. In a particular example, the number of vanes is equal to N+1. Some embodiments may also reduce acoustic noise in comparison to other arrangements by allowing a slower rotational speed of fan 40 for a given amount of airflow.
FIG. 7 is a perspective view of thermal module 200 using system 1 according to some embodiments. Thermal module 200 also includes housing 210, electronic component 300, and heat sink 310. Relevant portions of housing 210 are drawn as if transparent to allow viewing of electronic component 300 and heat sink 310. Thermal module 200 uses air 80 generated by system 1 to cool heat sink 310 according to some embodiments.
Electronic component 300 may comprise any heat-dissipating component, including but not limited to an integrated circuit (e.g., microprocessor, chipset), and a power switching element. Heat sink 310 may comprise any material (e.g. copper, aluminum) and may comprise any currently- or hereafter-known cooling device. As illustrated, heat sink 310 includes thermally-conductive fins 315 to dissipate heat from electronic component 300 into the ambient air.
The above-described increased in the axial velocity component of air 80 with respect to its tangential velocity component may reduce turning losses at the edge of fins 315 as compared to other systems. More efficient cooling of component 300 may result. In addition, for a given speed of fan 40, a static pressure of air exiting module 200 may be greater than previously available.
FIG. 8 is a perspective view of system 400 according to some embodiments. System 400 may comprise a desktop computing platform. System 400 uses air 80 generated by thermal module 200 to cool multiple system components.
System 400 includes module 200, chassis 410, and motherboard 420. Chassis 410 is shown transparent to allow viewing of the components of system 400. Module 200 of FIG. 7 may be identical to module 200 of FIG. 6 except for the vertical extension of system 1 below motherboard 420. The vertical extension may allow a portion of air 80 to travel from blades 30 to a volume between motherboard 420 and chassis 410.
Various components may be mounted to motherboard 420, including memory controller hub 430, I/O controller hub 440, add-in cards 450, 452 and 454, memory cards 460, and I/O interfaces 470. Also included in system 400 are removable media drive 480, hard disk drive 490 and power supply 500. Any other system components and configurations may be used in conjunction with some embodiments.
Air 80 from thermal module may be used to cool one or more of the components of system 400. In some examples, air 80 may flow over heat-dissipating components mounted on a face of graphics add-in card 450, over hubs 430 and 440, and may exit through a rear panel of chassis 410 (not shown). The increased axial flow with respect to tangential flow of air 80 from system 1 may reduce losses caused by heat sink 310, thereby making more air pressure available to cool the other components. If additional air pressure is not needed, system 1 may be operated at a lower fan speed and acoustic level so as to deliver a same amount of airflow as a conventional system operating at a higher fan speed and acoustic level.
The several embodiments described herein are solely for the purpose of illustration. Embodiments may include any currently or hereafter-known versions of the elements described herein. Therefore, persons in the art will recognize from this description that other embodiments may be practiced with various modifications and alterations.

Claims

1. An apparatus comprising:

a housing;

a hub; and

a plurality of airfoils, each of the plurality of airfoils having a leading edge, a trailing edge, a first end, and a second end,

wherein the first end of each of the plurality of airfoils is fixedly coupled to the hub and wherein the second end of each of the plurality of airfoils is fixedly coupled to the housing.

2. An apparatus according to claim 1,

wherein a maximum camber of at least one of the plurality of airfoils is 8% or more of a length of the at least one of the plurality of airfoils.

3. An apparatus according to claim 2, wherein each of the plurality of airfoils complies with at least one of NACA 93xx, 94xx, 83xx, or 84xx airfoil geometries.

4. An apparatus according to claim 1, wherein the leading edge of at least one of the plurality of airfoils defines a first curve to reduce a tangential velocity vector and increase a static pressure vector of air received at the leading edge.

5. An apparatus according to claim 4, further comprising:

a fan to deliver the air to the leading edges of the plurality of airfoils, the fan comprising a plurality of fan blades,

wherein the first curve is disposed perpendicular at a given radius to a trailing edge of at least one of the plurality of fan blades at the given radius.

6. An apparatus according to claim 1, wherein the leading edge of at least one of the plurality of airfoils defines a first curve to reduce a radial velocity vector and increase a static pressure vector of air received at the leading edge.

7. An apparatus according to claim 6, further comprising:

wherein the first curve is disposed substantially perpendicular at a given radius to a trailing edge of at least one of the plurality of fan blades at the given radius.

8. An apparatus according to claim 1, wherein the first end is not coplanar with the second end.

9. An apparatus according to claim 8, wherein the vane angle of at least one of the plurality of airfoils is 55 degrees at the hub and 75 degrees at the housing.

10. An apparatus according to claim 8, wherein the vane angle of at least one of the plurality of airfoils is 43 degrees at the hub and 73 degrees at the housing.

11. An apparatus according to claim 8, wherein the vane angle increases with distance from the hub.

12. An apparatus according to claim 8, wherein the leading edge of at least one of the plurality of airfoils defines a first curve to reduce a radial velocity vector and a tangential velocity vector and to increase a static pressure vector of air received at the leading edge.

13. An apparatus according to claim 1, further comprising:

a fan to deliver the air to the leading edges of the plurality of airfoils, the fan comprising only N fan blades,

wherein the apparatus comprises only M airfoils, and

wherein M is not an integer multiple of N.

14. An apparatus according to claim 13, further comprising:

a fan motor disposed within the fan and coupled to the hub,

wherein the fan is coupled to the fan motor.

15. An apparatus according to claim 13, wherein M is equal to N+1.

16. A system comprising:

a housing;

a hub;

a plurality of airfoils, each of the plurality of airfoils having a leading edge, a trailing edge, a first end, and a second end;

a microprocessor; and

an aluminum and copper composite heatsink coupled to the microprocessor, the heatsink to receive air from the trailing edges of the plurality of airfoils,

17. A system according to claim 16,

18. A system according to claim 17, wherein each of the plurality of airfoils complies with at least one of NACA 93xx, 94xx, 83xx, or 84xx airfoil geometries.

19. A system according to claim 16, wherein the leading edge of at least one of the plurality of airfoils defines a first curve to reduce a tangential velocity vector and increase a static pressure vector of air received at the leading edge.

20. A system according to claim 19, further comprising:

21. A system according to claim 16, wherein the leading edge of at least one of the plurality of airfoils defines a first curve to reduce a radial velocity vector and increase a static pressure vector of air received at the leading edge.

22. A system according to claim 21, further comprising:

23. A system according to claim 16, wherein the first end is not coplanar with the second end.

24. A system according to claim 23, wherein the vane angle of at least one of the plurality of airfoils is 55 degrees at the hub and 75 degrees at the housing.

25. A system according to claim 23, wherein the vane angle of at least one of the plurality of airfoils is 43 degrees at the hub and 73 degrees at the housing.

26. A system according to claim 23, wherein the vane angle increases with distance from the hub.

27. A system according to claim 23, wherein the leading edge of at least one of the plurality of airfoils defines a first curve to reduce a radial velocity vector and a tangential velocity vector and to increase a static pressure vector of air received at the leading edge.

28. A system according to claim 16, further comprising:

wherein the apparatus comprises only M airfoils, and

wherein M is not an integer multiple of N.

29. A system according to claim 28, further comprising:

a fan motor disposed within the fan and coupled to the hub,

wherein the fan is coupled to the fan motor.

30. A system according to claim 28, wherein M is equal to N+1.