Passive two phase heat transfer systems

1. A method for pool boiling, comprising:

introducing a liquid into a chamber of a housing, wherein the chamber comprises a heat transfer surface, comprising one or more protruding features which form channels, and a first asymmetric diverter positioned over the heat transfer surface and extending at least partially across the one or more protruding features in the chamber and a passageway between the heat transfer surface and the asymmetric diverter;

forming, at one or more nucleation sites on the heat transfer surface, one or more bubbles in the liquid on the surface of the chamber at the one or more bubble nucleation sites; and

enhancing the flow of the liquid through the channels by redirecting with the first asymmetric diverter the growth and path of one of the one or more bubbles preferentially in one direction as they form and grow so that the one or more bubbles push liquid out away from the growing one or more bubbles, wherein the one or more bubbles escape out of the passageway only out one side of the first asymmetric diverter causing liquid to flow into the passageway in the other side of the first asymmetric diverter, wherein the liquid flow is caused without an external pumping mechanism and wherein the liquid flow improves heat transfer and increases the critical heat flux limit.

2. The method of claim 1 , further comprising:

introducing the liquid into the chamber of the housing, wherein the chamber comprises a second asymmetric diverter positioned over the heat transfer surface and extending at least partially across the one or more protruding features in the chamber, arranged adjacent to the first diverter to form a shared first opening between the first and second diverters and a passageway between the heat transfer surface and the first and second diverters; and

enhancing the flow of the liquid through the channels by redirecting with the first and second diverters the growth and path of one of the one or more bubbles preferentially in one direction as they form and grow so that the one or more bubbles push liquid out away from the growing one or more bubbles, wherein the one or more bubbles escape out of the passageway only through the shared first opening between adjacent diverters causing liquid flow into the passageway around the other side of each of the first and second diverters or the one or more bubbles escape out of the passageway only around the other side of each of the first and second diverters causing liquid flow into the passageway through the shared first opening between the first and second diverters.

3. The method of claim 2 , further comprising:

introducing the liquid into the chamber of the housing, wherein the chamber comprises three or more asymmetric diverters positioned over the heat transfer surface and extending at least partially across the one or more protruding features in the chamber, arranged adjacent to one another with a diverter at each end, wherein each diverter between the end diverters forms a shared opening on one side with an adjacent diverter and a shared opening on the other side with an adjacent diverter and a passageway between the heat transfer surface and the three or more asymmetric diverters; and

enhancing the flow of the liquid through the channels by redirecting with each one of the three or more diverters the growth and path of one of the one or more bubbles preferentially in one direction as they form and grow so that the one or more bubbles push liquid out away from the growing one or more bubbles, wherein the one or more bubbles escape out of the passageway only through the shared opening between adjacent diverters causing liquid flow into the passageway around the other side of each of the adjacent diverters or the one or more bubbles escape out of the passageway only around the other side of adjacent diverters causing liquid flow into the passageway through the shared opening between the adjacent diverters.

4. The method as set forth in claim 1 , wherein the one or more protruding features comprise one or more fins.

5. The method as set forth in claim 4 , wherein the one or more fins are in an offset arrangement in the chamber.

6. The method as set forth in claim 1 , wherein the one or more protruding features comprise one or more pins.

7. The method as set forth in claim 1 , wherein the forming one or more bubbles further comprises triggering the bubble nucleation in the chamber of the housing to form the one or more bubbles.

8. A pool boiling apparatus comprising:

a housing with a chamber;

a heat transfer surface, comprising one or more protruding features which form channels in the chamber of the housing; and

a first asymmetric diverter positioned over the heat transfer surface and extending at least partially across the one or more protruding features in the chamber and a passageway between the heat transfer surface and the asymmetric diverter, wherein the chamber of the housing is configured to form at one or more nucleation sites on the heat transfer surface one or more bubbles as a result of bubble nucleation creating a flow of the liquid on the heat transfer surface from which they have formed and wherein the first asymmetric diverter redirects the growth and path of the one or more bubbles preferentially in one direction as they form and grow so that the one or more bubbles push liquid out away from the growing one or more bubbles, wherein the one or more bubbles escape out of the passageway only out one side of the first asymmetric diverter causing liquid to flow into the passageway in the other side of the first asymmetric diverter, without an external pumping mechanism so as to improve heat transfer to the liquid and increase the critical heat flux limit.

9. The apparatus of claim 8 , further comprising:

a second asymmetric diverter positioned over the heat transfer surface and extending at least partially across the one or more protruding features in the chamber, arranged adjacent to the first diverter to form a shared first opening between the first and second diverters and a passageway between the heat transfer surface and the first and second diverters;

wherein the chamber of the housing is configured to enhance the flow of the liquid through the channels by redirecting with the first and second diverters the growth and path of one of the one or more bubbles preferentially in one direction as they form and grow so that the one or more bubbles push liquid out away from the growing one or more bubbles, wherein the one or more bubbles escape out of the passageway only through the shared first opening between adjacent diverters causing liquid flow into the passageway around the other side of each of the first and second diverters or the one or more bubbles escape out of the passageway only around the other side of each of the first and second diverters causing liquid flow into the passageway through the shared first opening between the first and second diverters.

10. The apparatus of claim 9 , further comprising:

three or more asymmetric diverters positioned over the heat transfer surface and extending at least partially across the one or more protruding features in the chamber, arranged adjacent to one another with a diverter at each end, wherein each diverter between the end diverters forms a shared opening on one side with an adjacent diverter and a shared opening on the other side with an adjacent diverter and a passageway between the heat transfer surface and the three or more asymmetric diverters;

wherein the chamber of the housing is configured to enhance the flow of the liquid through the channels by redirecting with each one of the three or more diverters the growth and path of one of the one or more bubbles preferentially in one direction as they form and grow so that the one or more bubbles push liquid out away from the growing one or more bubbles, wherein the one or more bubbles escape out of the passageway only through the shared opening between adjacent diverters causing liquid flow into the passageway around the other side of each of the adjacent diverters or the one or more bubbles escape out of the passageway only around the other side of adjacent diverters causing liquid flow into the passageway through the shared opening between the adjacent diverters.

11. The apparatus of claim 8 , wherein the one or more protruding features comprise one or more fins.

12. The apparatus of claim 11 , wherein the one or more fins are in an offset arrangement in the chamber.

13. The apparatus of claim 8 , wherein the one or more protruding features comprise one or more pins.

14. The apparatus of claim 8 , wherein at least one of the chamber of the housing with the one or more protruding features and the diverter is configured to trigger the bubble nucleation in the chamber of the housing to form the one or more bubbles.

15. A method for pool boiling, comprising:

introducing a liquid into a chamber of a housing, wherein the chamber comprises a heat transfer surface, a first asymmetric diverter positioned over the heat transfer surface and a microgap between the heat transfer surface and the first asymmetric diverter;

forming, at one or more nucleation sites on the heat transfer surface, one or more bubbles in the liquid on the surface of the chamber at the one or more bubble nucleation sites; and

enhancing the flow of the liquid by redirecting with the first asymmetric diverter the growth and path of one of the one or more bubbles preferentially in one direction as they form and grow so that the one or more bubbles push liquid out away from the growing one or more bubbles, wherein the one or more bubbles escape out of the microgap only out one side of the first asymmetric diverter causing liquid to flow into the microgap in the other side of the first asymmetric diverter, wherein the liquid flow is caused without an external pumping mechanism and wherein the liquid flow improves heat transfer and increases the critical heat flux limit.

16. The method of claim 15 , further comprising:

introducing the liquid into the chamber of the housing, wherein the chamber comprises a second asymmetric diverter positioned over the heat transfer surface arranged adjacent to the first diverter to form a shared first opening between the first and second diverters, the microgap between the heat transfer surface and the first and second diverters; and

enhancing the flow of the liquid by redirecting with the first and second diverters the growth and path of one of the one or more bubbles preferentially in one direction as they form and grow so that the one or more bubbles push liquid out away from the growing one or more bubbles, wherein the one or more bubbles escape out of the microgap only through the shared first opening between adjacent diverters causing liquid flow into the microgap around the other side of each of the first and second diverters or the one or more bubbles escape out of the microgap only around the other side of each of the first and second diverters causing liquid flow into the microgap through the shared first opening between the first and second diverters.

17. The method of claim 16 , further comprising:

introducing the liquid into the chamber of the housing, wherein the chamber comprises three or more asymmetric diverters positioned over the heat transfer surface arranged adjacent to one another with a diverter at each end, wherein each diverter between the end diverters forms a shared opening on one side with an adjacent diverter and a shared opening on the other side with an adjacent diverter and the microgap between the heat transfer surface and the three or more asymmetric diverters; and

enhancing the flow of the liquid by redirecting with each one of the three or more diverters the growth and path of one of the one or more bubbles preferentially in one direction as they form and grow so that the one or more bubbles push liquid out away from the growing one or more bubbles, wherein the one or more bubbles escape out of the microgap only through the shared opening between adjacent diverters causing liquid flow into the microgap around the other side of each of the adjacent diverters or the one or more bubbles escape out of the microgap only around the other side of adjacent diverters causing liquid flow into the microgap through the shared opening between the adjacent diverters.

18. The method of claim 17 , further comprising protruding features on the heat transfer surface located beneath the microgap.

19. A pool boiling apparatus comprising:

a housing with a chamber;

a heat transfer surface;

a first asymmetric diverter positioned over the heat transfer surface and a microgap between the heat transfer surface and the first asymmetric diverter, wherein the chamber of the housing is configured to form at one or more nucleation sites on the heat transfer surface one or more bubbles as a result of bubble nucleation creating a flow of the liquid on the heat transfer surface from which they have formed and wherein the first asymmetric diverter redirects the growth and path of the one or more bubbles preferentially in one direction as they form and grow so that the one or more bubbles push liquid out away from the growing one or more bubbles, wherein the one or more bubbles escape out of the microgap only out one side of the first asymmetric diverter causing liquid to flow into the microgap in the other side of the first asymmetric diverter, without an external pumping mechanism so as to improve heat transfer to the liquid and increase the critical heat flux limit.

20. The apparatus of claim 19 , further comprising:

a second asymmetric diverter positioned over the heat transfer surface and arranged adjacent to the first diverter to form a shared first opening between the first and second diverters and the microgap between the heat transfer surface and the first and second diverters;

wherein the chamber of the housing is configured to enhance the flow of the liquid through the channels by redirecting with the first and second diverters the growth and path of one of the one or more bubbles preferentially in one direction as they form and grow so that the one or more bubbles push liquid out away from the growing one or more bubbles, wherein the one or more bubbles escape out of the microgap only through the shared first opening between adjacent diverters causing liquid flow into the microgap around the other side of each of the first and second diverters or the one or more bubbles escape out of the microgap only around the other side of each of the first and second diverters causing liquid flow into the microgap through the shared first opening between the first and second diverters.