Radial flow micro-channel heat sink with impingement cooling
A heat sink removes heat from an electronic device and comprises a base, a lid. An inner ring of first fins extend radially outwardly first length from an inner circle and extend axially a first height from the top surface of the base, and an outer ring of second fins extend radially inwardly a second length from an outer periphery and extend axially a second height from the top surface of the base. A confining plate extends radially above the fins and is spaced below the bottom surface of the lid whereby coolant fluid flows from an inlet opening of the lid through the center opening of the confining plate and radially outwardly through the fins and upward around the outer edge of the confining plate and into the space above the confining plate to an outlet opening. A nozzle having a throat is disposed above the lid and extends below the lid to the confining plate. A flow diverter extends upwardly from the top surface of the base and into and through the throat of the nozzle.
1. A heat sink assembly for removing heat from an electronic device, said assembly comprising:
a base having a top surface,
a lid having a bottom surface in spaced relationship with and parallel to said top surface of said base,
said lid defining an inlet opening on an inlet axis,
an outer wall extending vertically between said top surface of said base and said bottom surface of said lid and about said inlet axis,
a plurality of fins extending upwardly from said top surface of said base and extending radially from an inner circle concentric with said inlet axis toward an outer periphery disposed about said inlet axis for directing the flow of cooling fluid radially from said inlet axis, and
characterized by a confining plate having a center opening for receiving the flow of coolant fluid from said inlet opening in said lid and extending radially from said center opening above said fins and spaced below said bottom surface of said lid.
2. An assembly as set forth in claim 1 wherein said confining plate extends radially from said center opening to an outer edge spaced radially inwardly from said outer wall.
3. An assembly as set forth in claim 2 wherein said lid defines an outlet opening disposed above said confining plate whereby coolant fluid flows from said inlet opening of said lid through said center opening of said confining plate and radially outwardly through said fins and upward around said outer edge of and above said confining plate to said outlet opening.
4. An assembly as set forth in claim 1 wherein said plurality of fins includes a plurality of first fins extending radially outwardly from said inner circle first length and extending axially a first height from said top surface of said base and a plurality of second fins extending radially inwardly from said outer periphery a second length and extending axially a second height from said top surface of said base, said first height being less than said second height.
5. An assembly as set forth in claim 4 wherein one of said first fins is radially aligned with every other one of said second fins.
6. An assembly as set forth in claim 5 including a flow diverter extending upwardly about said inlet axis from said top surface of said base toward said bottom surface of said lid whereby said inlet opening and said center opening are aligned with said flow diverter for impinging the flow of cooling fluid on said flow diverter to re-direct the flow of fluid radially outwardly between said fins.
7. An assembly as set forth in claim 2 including a nozzle disposed in said inlet opening of said lid for delivering coolant flow to said center opening of said confining plate.
8. An assembly as set forth in claim 7 wherein said nozzle extends below said lid and is in sealed engagement with said center opening of said confining plate.
9. An assembly as set forth in claim 8 wherein said nozzle includes an entry portion converging to a throat and an exit portion diverging from said throat.
10. An assembly as set forth in claim 9 wherein said throat of said nozzle is disposed above said lid and said diverging exit portion extends through and in sealing engagement with said lid to said center opening of said confining plate.
11. An assembly as set forth in claim 2 wherein selected ones of said fins extend and cross at said axis.
12. An assembly as set forth in claim 11 wherein said selected fins include two pairs of aligned fins crossing at right angles at said axis.
13. An assembly as set forth in claim 2 wherein said outer periphery of said fins defines a circle.
14. An assembly as set forth in claim 2 wherein said outer periphery of said fins defines a square.
15. An assembly as set forth in claim 1 including a flow diverter extending upwardly about said inlet axis from said top surface of said base toward said bottom surface of said lid whereby said inlet opening and said center opening are aligned with said flow diverter for impinging the flow of cooling fluid on said flow diverter to re-direct the flow of fluid radially outwardly, a nozzle disposed in said inlet opening of said lid for delivering coolant flow to said center opening of said confining plate, said flow diverter extending upwardly from said top surface of said base and into said nozzle.
16. An assembly as set forth in claim 15 wherein said flow diverter has a decreasing circular cross-section from said top surface of said base and into said nozzle.
17. An assembly as set forth in claim 16 wherein said flow diverter has a conical top.
18. An assembly as set forth in claim 15 wherein said flow diverter has a cross-section forming an X from said top surface of said base and into said nozzle.
19. An assembly as set forth in claim 15 wherein said top surface of said base includes a dished shaped recess disposed about said flow diverter.
20. An assembly as set forth in claim 1 wherein said plurality of fins extend upwardly from said top surface of said base higher in a predetermined sector about said inlet axis.
21. An assembly as set forth in claim 1 wherein said plurality of fins extend higher upwardly in wave-like fashion from said top surface of said base in a predetermined sector about said inlet axis.
22. An assembly as set forth in claim 3 including a fluid pump for circulating a flow of cooling fluid to said inlet opening and a heat exchanger for removing heat from the flow of cooling fluid exiting said outlet opening.
23. A heat sink assembly for removing heat from an electronic device, said assembly comprising:
a base having a top surface,
a lid having a bottom surface in spaced relationship with and parallel to said top surface of said base,
said lid defining an inlet opening on an inlet axis,
an outer wall extending vertically between said top surface of said base and said bottom surface of said lid and about said inlet axis,
a plurality of first fins extending radially first length from an inner circle a concentric with said inlet axis toward an outer periphery disposed about said inlet axis for directing the flow of cooling fluid radially from said inlet axis,
said first fins extending axially a first height h 1 from said top surface of said base,
a plurality of second fins extending radially inwardly from said outer periphery a second length and extending axially a second height from said top surface of said base,
one of said first fins being radially aligned with every other one of said second fins,
said first height being less than said second height from said top surface of said base,
a confining plate having a center opening for receiving the flow of coolant fluid from said inlet opening in said lid and extending radially from said center opening above said fins and spaced below said bottom surface of said lid to an outer edge spaced radially inwardly from said outer wall,
a nozzle having entry portion converging to a throat and an exit portion diverging from said throat with said throat being disposed above said lid and said diverging exit portion extending through and in sealing engagement with said lid and into sealing engagement with said center opening of said confining plate, and
said lid defines an outlet opening disposed above said confining plate whereby coolant fluid flows through said nozzle in said lid to said center opening of said confining plate and radially outwardly through said fins and upward around said outer edge of and above said confining plate to said outlet opening.
24. An assembly as set forth in claim 23 including a flow diverter extending upwardly about said inlet axis from said top surface of said base and into said nozzle for impinging the flow of cooling fluid on said flow diverter to re-direct the flow of fluid radially outwardly between said fins.
25. An assembly as set forth in claim 24 wherein said top surface of said base includes a dished shaped recess disposed about said nozzle.