SHEAR DRIVEN MICRO-FLUIDIC PUMP

• US 20140240916A1
• Filed: 07/22/2013
• Published: 08/28/2014
• Est. Priority Date: 02/27/2013
• Status: Active Grant

• Current Assignee: AAR Aerospace Consulting, LLC
• Original Assignee: AAR Aerospace Consulting, LLC
• Inventors: Daidzic, Nihad
• Granted Patent: US 9,528,503 B2
• Time in Patent Office: Days
• US Class Current: 361/679.46
• CPC Class Codes: B23P 15/26 heat exchangers or the like making heat exchangers by methods covered by other subclasses B21D53/02
• CPC Class Codes: F04B 17/04 using solenoids
• CPC Class Codes: F04B 19/006 Micropumps F04B43/043 and F04B43/095 take precedence
• CPC Class Codes: F04B 35/045 using solenoids
• CPC Class Codes: F04B 43/043 Micropumps
• CPC Class Codes: F04B 53/08 Cooling; Heating; Preventing freezing
• CPC Class Codes: G06F 1/20 Cooling means
• CPC Class Codes: H05K 7/20172 Fan mounting or fan specifications
• CPC Class Codes: H05K 7/20263 Heat dissipaters releasing heat from coolant
• CPC Class Codes: H05K 7/20272 Accessories for moving fluid, for expanding fluid, for connecting fluid conduits, for distributing fluid, for removing gas or for preventing leakage, e.g. pumps, tanks or manifolds
• CPC Class Codes: Y10T 29/4935 Heat exchanger or boiler making

Abstract

An example includes an apparatus to pump a fluid. The apparatus includes a housing extending along a length defining an elongate interior, an actuator in the housing, conforming to the elongate interior, the actuator including a plurality of lumens, each having a length extending substantially parallel to the elongate interior, each from around 10 to 200 micrometers across and an actuator configured to oscillate the actuator in the actuator housing along the length of the elongate interior with a rate differential between movement in a first direction versus movement in a second direction opposite the first direction to pump the fluid.

Claims

1. An apparatus to pump a fluid, comprising:

a housing extending along a length defining an elongate interior;

an actuator in the housing, conforming to the elongate interior, the actuator including a plurality of lumens, each having a length extending substantially parallel to the elongate interior, each from around 10 to 200 micrometers across; and

an actuator configured to oscillate the actuator in the actuator housing along the length of the elongate interior with a rate differential between movement in a first direction versus movement in a second direction opposite the first direction to pump the fluid.

2. The apparatus of claim 1, wherein at least one of the plurality of lumens has a circular shape in cross-section.

3. The apparatus of claim 1, wherein at least one of the plurality of lumens has a rectilinear shape in cross-section.

4. The apparatus of claim 1, wherein the actuator includes a micro-solenoid to be powered by a 5V DC source.

5. The apparatus of claim 1, wherein the actuator includes a linear motor to be powered by a DC source.

6. The apparatus of claim 1, wherein the actuator includes a Piezo-electric transducer with a force/stroke converter.

7. The apparatus of claim 1, wherein the plurality of lumens comprise from around 60% to 80% of a cross-sectional area of the actuator.

8. The apparatus of claim 7, wherein the plurality of lumens comprise from around 78.5% of a cross-sectional area of the actuator.

9. The apparatus of claim 1, wherein the movement in the first direction is a first distance from 0.5 to 5 millimeters in 100 to 500 milliseconds, and movement in the second direction is a second distance 0.5 to 5 millimeters in 1 to 2 milliseconds.

10. The apparatus of claim 9, wherein the first distance and the second distance are substantially equivalent.

11. The apparatus of claim 9, wherein the actuator is configured to move in the first direction at an average speed of around 30-50 millimeters per second.

12. The apparatus of claim 1, wherein the movement in the second direction is at a frequency that is from around 100 to around 1000 times faster than movement in the first direction.

13. The apparatus of claim 12, wherein the movement in the second direction is around 1000 hertz, and movement in the first direction is at around 10 hertz.

14. The apparatus of claim 12, wherein the movement in the second direction is around 10000 hertz, and movement in the first direction is at around 10 hertz.

15. The apparatus of claim 12, wherein the movement in the second direction is around 2000-5000 hertz, and movement in the first direction is at from around 20-50 hertz.

16. The apparatus of claim 1, wherein the actuator is comprised of co-axial cylinders intersected by radial spreaders defining a plurality of curved slits.

17. The apparatus of claim 16, wherein each of the slits has a slit-bisecting arc length of from 25-200 micrometers.

18. The apparatus of claim 16, wherein each of the slits has a radial width of around 50 micrometers.

19. The apparatus of claim 16, wherein at least one of the co-axial cylinders is around 50 micrometers in thickness.

20. The apparatus of claim 1, wherein the housing is formed of at least one of plastic and metal.

21. The apparatus of claim 20, wherein the housing is at least one of a micro-molded housing and a micro-cast housing.

22. The apparatus of claim 1, wherein the plurality of lumens are distributed according to a regular pattern.

23. The apparatus of claim 1, wherein the plurality of lumens are distributed according to a random pattern.

24. The apparatus of claim 1, comprising valve disposed in the actuator.

25. The apparatus of claim 24, wherein the valve includes a gurney-type valve.

26. The apparatus of claim 1, wherein the actuator is made of plastic.

47. A computer cooling system including a heat exchanger to reject heat to the ambient and a second heat exchanger to absorb heat from an integrated circuit, with a cooling loop including a fluid to flow between the heat exchanger and the second heat exchanger, pumped by the apparatus of claim 1.

48. Using the apparatus of claim 1 for heat exchange between a heat source and a heat exchanger, comprising:

affixing the heat exchanger to the heat source, with the heat exchanger thermally communicative with the heat source;

pumping a fluid through the heat exchanger, at a determined flow rate and fluid pressure, by oscillating an actuator in a pump housing extending along a length defining an elongate interior, the actuator conforming to the elongate interior, the actuator including a plurality of lumens, each having a length extending substantially parallel to the elongate interior, each from around 20 to 200 micrometers across, wherein an oscillation takes place with a rate differential between movement in a first direction versus movement in a second direction opposite the first direction; and

exchanging heat between the heat exchanger and the heat source.

27. A method for heat exchange between a heat source and a heat exchanger, comprising:

affixing the heat exchanger to the heat source, with the heat exchanger thermally communicative with the heat source;

pumping a fluid through the heat exchanger, at a determined flow rate and fluid pressure, by oscillating an actuator in a pump housing extending along a length defining an elongate interior, the actuator conforming to the elongate interior, the actuator including a plurality of lumens, each having a length extending substantially parallel to the elongate interior, each from around 20 to 200 micrometers across, wherein an oscillation takes place with a rate differential between movement in a first direction versus movement in a second direction opposite the first direction; and

exchanging heat between the heat exchanger and the heat source.

28. The method of claim 27, wherein pumping includes pumping the fluid at a minimum of 80% of an actuator speed.

29. The method of claim 27, wherein pumping includes maintaining a Reynolds number of the fluid while the actuator is moving in the first direction to be 1/100^th the Reynolds number of the fluid while the actuator is moving in the second direction.

30. The method of claim 27, wherein pumping includes sensing a flow rate and adjusting the oscillation in association with the flow rate.

31. The method of claim 27, wherein pumping includes sensing a differential pressure and adjusting the oscillation in association with the differential pressure.

32. The method of claim 27, wherein pumping includes sensing a temperature and adjusting the oscillation in association with the temperature.

33. The method of claim 27, wherein pumping the fluid includes pumping at a flow rate of up to 100 milliliters per second, at a pressure of up to 40 kilopascals.

34. A heat exchange system for heat exchange with an integrated circuit, the system comprising:

a circulation loop to contain a fluid;

a heat emission portion in fluid communication with the circulation loop and configured to exchange heat with a cold source;

at least one heat absorption portion in fluid communication with the circulation loop and configured to exchange heat with the integrated circuit; and

a pump to pump a fluid through the circulation loop, the pump including;

a housing extending along a length defining an elongate interior;

an actuator in the housing, conforming to the elongate interior, the actuator including a plurality of lumens, each having a length extending substantially parallel to the elongate interior, each from around 20 to 200 micrometers across; and

an actuator configured to oscillate the actuator in the actuator housing along the length of the elongate interior with a rate differential between movement in a first direction versus movement in a second direction opposite the first direction to pump the fluid.

35. The system of claim 34, wherein the pump is a first pump, and comprising a second pump coupled to the circulation loop in parallel with the first pump.

36. The system of claim 35, wherein the actuator is configured to oscillate the first pump and the second pump.

37. The system of claim 35, comprising a third pump coupled to the circulation loop in series with the first pump.

38. The system of claim 37, comprising a fourth pump coupled to the circulation loop in parallel with the third pump.

39. The system of claim 38, wherein the pump is from around 30 millimeters in length, 15 millimeters in width and 15 millimeters in height.

40. The system of claim 38, wherein the actuator is configured to oscillate the third pump and the fourth pump.

41. The system of claim 34, wherein the pump is a first pump, and comprising a second pump coupled to the circulation loop in series with the first pump.

42. The system of claim 34, wherein the integrated circuit forms a part of a computer comprising a random access memory.

43. The system of claim 34, wherein the integrated circuit forms a part of a computer comprising an embedded processor.

44. The system of claim 34, comprising a flow rate sensor to sense a flow rate, wherein the pump is configured to adjust the oscillation in association with the flow rate.

45. The system of claim 34, comprising a temperature sensor to sense a temperature, wherein the pump is configured to adjust the oscillation in association with the temperature.

46. The system of claim 34, comprising a differential pressure sensor to sense a differential pressure, wherein the pump is configured to adjust the oscillation in association with the differential pressure.