Locally Enhanced Direct Liquid Cooling System for High Power Applications

• US 20170020027A1
• Filed: 07/15/2015
• Published: 01/19/2017
• Est. Priority Date: 07/15/2015
• Status: Active Grant

• Current Assignee: Hong Kong Applied Science And Technology Research Institute Co., Ltd.
• Original Assignee: Hong Kong Applied Science And Technology Research Institute Co., Ltd.
• Inventors: LV, Ya, GAO, Ziyang, TSUI, Yat Kit
• Granted Patent: US 9,713,284 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: F28F 3/022 the means being wires or pins
• CPC Class Codes: H01L 23/3735 Laminates or multilayers, e.g. direct bond copper ceramic substrates
• CPC Class Codes: H01L 23/473 by flowing liquids H01L23/4332, H01L23/4338 take precedence
• CPC Class Codes: H05K 7/20218 using a liquid coolant without phase change in electronic enclosures in cabinets of standardized dimensions H05K7/20536; in server cabinets H05K7/20709; in vehicle electronic casings H05K7/20845; in power control electronics H05K7/2089; in displays H05K7/20954
• CPC Class Codes: H05K 7/20254 Cold plates transferring heat from heat source to coolant
• CPC Class Codes: H05K 7/20927 Liquid coolant without phase change

Abstract

The present invention discloses a fluid cooling assembly which facilitates turbulent flow inside the assembly so as to achieve better heat dissipating effect. The cooling assembly comprises an enclosed chamber with an inlet and an outlet for fluid to pass through; together with a heat spreader; a plurality of micropillars and a plurality of heat dissipating fins installed inside the assembly. When fluid flows through the chamber, these elements in combination are adapted to create an enhanced turbulent flow upon the fluid so as to effectively dissipate heat from said heat spreader through the fluid.

Claims

1. A cooling assembly, comprising:

a) a receiving area on a first surface of a first plate adapted to receive at least one heat generating element;

b) a heat spreader comprising an inner surface and at least one outer surface;

said inner surface affixed to a second surface of said first plate adjacently opposite to said receiving area to conductively dissipate heat generated from said at least one heat generating element;

c) a plurality of heat dissipating fins spaced apart from each other;

each said heat dissipating fin coupled to a second plate and extending transversely therefrom to couple to said heat spreader, wherein said second plate is positioned opposite to said first plate with a space created therebetween to form a channel; and

d) a plurality of micropillars disposed on at least a portion of said at least one outer surface of said heat spreader;

said plurality of micropillars is disposed in a predetermined pattern,

wherein when fluid flows through said channel between said first plate and said second plate, said plurality of heat dissipating fins, said heat spreader and said plurality of micropillars in combination are adapted to create an enhanced turbulent flow upon said fluid so as to effectively dissipate heat from said heat spreader through said fluid.

2. The cooling assembly of claim 1, wherein said at least one outer surface of said heat spreader forms a shape that proximates an isothermal surface;

said isothermal surface being formed when heat is dispersed from said at least one heat generating element through said inner surface into the interior of said heat spreader.

3. The cooling assembly of claim 2, wherein said heat spreader is a quasi-funnel shape selected from inverted truncated pyramid shape, inverted truncated cone shape, semi-oval shape, hemisphere shape and hemi-ellipsoidal shape.

4. The cooling assembly of claim 1, wherein said plurality of micropillars is disposed in a predefined pattern around each of said plurality of heat dissipating fins.

5. The cooling assembly of claim 4, wherein said predefined pattern is a grid pattern and said plurality of micropillars is disposed at grid points of said grid pattern except on those locations that are occupied by said heat dissipating fins.

6. The cooling assembly according to claim 5, wherein said predefined pattern is an offset grid pattern comprising alternating first grid lines and second grid lines;

said second grid lines being a distance offset from said first grid lines wherein said plurality of micropillars is disposed at grid points of said offset grid pattern except on those locations that are occupied by said heat dissipating fins.

7. The cooling assembly of claim 4, wherein said plurality of micropillars is disposed around in close proximity but not contacting said heat dissipating fins.

8. The cooling assembly of claim 7 wherein said plurality of micropillars is disposed in pairs around each said heat dissipating fin;

each said pair being disposed proximate to each other, each said pair being located at a predetermined angle between a reference line and a central line of said pair;

said reference line and said central line of each pair being originated from a center of corresponding heat dissipating fin, and said reference line being in parallel with said fluid flow.

9. The cooling assembly of claim 8, wherein at least a first pair of micropillars is located at an angle within a range of 70 degree to 90 degree and at least a second pair of micropillars is located at an angle within a range of 130 degree to 150 degree.

10. The cooling assembly of claim 1 further comprising:

a) four side plates to form an enclosed chamber together with said first plate and said second plate;

one of said side plate comprising an inlet for fluid to enter into said chamber while another said side plate comprises an outlet for fluid to exit said chamber; and

b) a device that generates pressurized fluid, enabling said fluid to flow from said inlet to said outlet.

11. The cooling assembly of claim 1, wherein said micropillars are cylindrical shape with a diameter between 200 μ

m to 300 μ

m and a height between 200 μ

m to 300 μ

m.

12. The cooling assembly of claim 1 further comprises a convex shape object extended from said second plate towards said heat spreader with a space therebetween.

13. An electronic apparatus, comprising:

a) at least one electronic module wherein said electronic module comprises at least one electronic component that generates heat; and

b) a cooling assembly, comprising;

(1) a receiving area on a first surface of a first plate adapted to receive at least one electronic module;

(2) a heat spreader comprising an inner surface and at least one outer surface;

said inner surface affixed to a second surface of said first plate adjacently opposite to said receiving area to conductively dissipate heat generated from said at least one electronic module;

(3) a plurality of heat dissipating fins spaced apart from each other;

each said heat dissipating fin coupled to a second plate and extending transversely therefrom to couple to said heat spreader, wherein said second plate is positioned opposite to said first plate with a space created therebetween to form a channel; and

(4) a plurality of micropillars disposed on at least a portion of said at least one outer surface of said heat spreader;

said plurality of micropillars is disposed in a predetermined pattern,

wherein when fluid flows through said channel between said first plate and said second plate, said plurality of heat dissipating fins, said heat spreader and said plurality of micropillars in combination are adapted to create an enhanced turbulent flow upon said fluid so as to effectively dissipate heat from said heat spreader through said fluid.

14. The electronic apparatus of claim 13, wherein said at least one outer surface of said heat spreader forms a shape that proximates an isothermal surface;

said isothermal surface being formed when heat is dispersed from said at least one electronic module through said inner surface into the interior of said heat spreader.

15. The electronic apparatus of claim 13, wherein said plurality of micropillars is disposed in a predefined pattern around each of said plurality of heat dissipating fins.

16. The electronic apparatus of claim 15, wherein said predefined pattern is a grid pattern and said plurality of micropillars is disposed at grid points of said grid pattern except on those locations that are occupied by said heat dissipating fins.

17. The electronic apparatus of claim 16, wherein said predefined pattern is an offset grid pattern comprising alternating first grid lines and second grid lines;

said second grid lines being a distance offset from said first grid lines wherein said plurality of micropillars is disposed at grid points of said offset grid pattern except on those locations that are occupied by said heat dissipating fins.

18. The electronic apparatus of claim 15, wherein said plurality of micropillars is disposed around in close proximity but not contacting said heat dissipating fin.

19. The electronic apparatus of claim 18, wherein said plurality of micropillars is disposed in pairs around each said heat dissipating fin;

each said pair being disposed proximate to each other;

each said pair being located at a predetermined angle between a reference line and a central line of said pair;

said reference line and said central line of each pair being originated from a center of corresponding heat dissipating fin, and said reference line being in parallel with said fluid flow.

20. The electronic apparatus of claim 13, wherein said micropillars are cylindrical shape with a diameter between 200 μ

m to 300 μ

m and a height between 200 μ

m to 300 μ

m.