Systems and methods for compressing plasma

• US 9,424,955 B2
• Filed: 07/03/2013
• Issued: 08/23/2016
• Est. Priority Date: 02/04/2009
• Status: Active Grant

• Current Assignee: General Fusion Inc.
• Original Assignee: General Fusion Inc.
• Inventors: Laberge, Michel Georges, Richardson, Douglas H.
• Primary Examiner(s): O'CONNOR, MARSHALL P
• Application Number:
  US13/935,281
• Publication Number:
  US 20140247913A1
• Time in Patent Office: 1,147 Days
• Field of Search: 376/133, 376/190, 376/199
• US Class Current: 1/1
• CPC Class Codes: G21B 1/057 Tokamaks
• CPC Class Codes: G21B 3/008 Fusion by pressure waves
• CPC Class Codes: H05H 1/16 using externally-applied electric and magnetic fields
• CPC Class Codes: H05H 1/54 Plasma accelerators
• CPC Class Codes: H05H 3/06 Generating neutron beams targets for producing nuclear reactions H05H6/00; neutron sources G21G4/02
• CPC Class Codes: Y02E 30/10 Nuclear fusion reactors

Abstract

Embodiments of systems and methods for compressing plasma are described in which plasma pressures above the breaking point of solid material can be achieved by injecting a plasma into a funnel of liquid metal in which the plasma is compressed and/or heated.

Claims

1. An apparatus for compressing plasma, the apparatus comprising:

a plasma gun configured to generate a compact toroid of plasma;

a plasma accelerator having a first end, a second end, and a longitudinal axis between the first end and the second end, the plasma accelerator configured to receive the compact toroid at the first end and to accelerate the compact toroid along the longitudinal axis toward the second end; and

a liquid funnel system comprising a liquid funnel and a liquid guide,

the liquid funnel having a substantially cylindrical passage substantially aligned with the longitudinal axis of the plasma accelerator, the liquid funnel having an inner surface,

the liquid guide extending along a longitudinal axis of the cylindrical passage, the liquid guide spaced apart from the inner surface of the liquid funnel thereby providing an annular space between the inner surface of the liquid funnel and an outer surface of the liquid guide,

the passage having a first inner diameter at a top end of the passage and a second inner diameter at a bottom end of the passage, the second inner diameter less than the first inner diameter,

the liquid funnel system configured to receive the compact toroid from the second end of the plasma accelerator and to compress the compact toroid as the compact toroid moves along the annular space from the top end of the passage toward the bottom end of the passage,

wherein the apparatus is configured such that a pressure of the compact toroid when below the top end of the passage is greater than a pressure of the compact toroid when above the top end of the passage.

2. The apparatus of claim 1, wherein the plasma gun has a gun axis that is substantially aligned with the longitudinal axis of the plasma accelerator.

3. The apparatus of claim 1, wherein the compact toroid comprises a spheromak.

4. The apparatus of claim 1, further comprising a capacitor bank configured to provide electrical energy to the plasma gun.

5. The apparatus of claim 4, further comprising a substantially disk-shaped transmission line configured to electrically couple the capacitor bank to the plasma gun.

6. The apparatus of claim 1, wherein the plasma gun comprises at least one magnetic coil.

7. The apparatus of claim 6, further comprising a cooling system configured to cool the at least one magnetic coil.

8. The apparatus of claim 1, wherein the plasma accelerator comprises an electromagnetic rail gun.

9. The apparatus of claim 1, wherein the plasma accelerator comprises a plasma restrictor located near the first end of the plasma accelerator, the plasma restrictor configured to inhibit movement of the compact toroid from above the location of the restrictor to below the location of the restrictor until a magnetic field strength of the accelerator exceeds a threshold value, wherein the plasma accelerator comprises a plasma propagation channel, and the plasma restrictor comprises a constriction in the plasma propagation channel.

10. The apparatus of claim 1, wherein the plasma accelerator comprises a plasma restrictor located near the first end of the plasma accelerator, the plasma restrictor configured to inhibit movement of the compact toroid from above the location of the restrictor to below the location of the restrictor until a magnetic field strength of the accelerator exceeds a threshold value, wherein the plasma restrictor comprises at least one magnetic coil disposed near the first end of the plasma accelerator.

11. The apparatus of claim 1, wherein the plasma accelerator comprises an inner electrode and an outer electrode, at least one of the inner electrode and the outer electrode configured with a taper to provide compression to the compact toroid as the toroid moves from the first end to the second end.

12. The apparatus of claim 11, wherein at least one of the inner electrode and the outer electrode is coated with a material having a melting point greater than a temperature of the compact toroid when the compact toroid is in the plasma accelerator.

13. The apparatus of claim 1, further comprising a capacitor bank configured to provide electrical energy to the plasma accelerator.

14. The apparatus of claim 13, further comprising a saturable inductor configured to delay the provision of the electrical energy from the capacitor bank to the plasma accelerator.

15. The apparatus of claim 14, wherein the saturable inductor is disposed in a disk-shaped transmission line configured to transmit the electrical energy from the capacitor bank to the plasma accelerator.

16. The apparatus of claim 14, wherein the saturable inductor comprises an amorphous metal.

17. The apparatus of claim 1, wherein the apparatus is configured such that a pressure of the compact toroid at the second end of the plasma accelerator is less than a material strength of the plasma accelerator at the second end of the plasma accelerator.

18. The apparatus of claim 17, wherein the apparatus is configured such that a pressure of the compact toroid when in the liquid funnel is above the material strength.

19. The apparatus of claim 1, wherein the liquid funnel comprises a liquid metal.

20. The apparatus of claim 19, wherein the liquid metal comprises lead-lithium.

21. The apparatus of claim 19, further comprising a pump system configured to supply the liquid metal to form the liquid funnel of the liquid funnel system.

22. The apparatus of claim 1, wherein the liquid funnel comprises a liquid material that flows at least partially under gravity from the top end to the bottom end.

23. The apparatus of claim 1, wherein the liquid guide is electrically conductive.

24. The apparatus of claim 23, wherein the liquid guide is configured to provide a magnetic force on the compact toroid when the compact toroid is below the top end of the passage.

25. The apparatus of claim 1, further comprising an injection system configured to inject the liquid guide into the liquid funnel system before the compact toroid reaches the top end of the liquid funnel.

26. The apparatus of claim 25, wherein the injection system is configured to provide the liquid guide into the liquid funnel system as a liquid material that flows at least partially under gravity, the liquid guide not in electrical contact with the liquid funnel when the compact toroid is below the top end of the funnel.

27. The apparatus of claim 26, further comprising a recirculation system configured to recirculate a portion of liquid material from the liquid funnel system to a reservoir configured to store liquid material for the liquid guide.

28. The apparatus of claim 27, wherein the recirculation system comprises an intermittent pump configured to recirculate the portion of the liquid material between successive injections of plasma into the liquid funnel system.

29. The apparatus of claim 28, wherein the recirculation system further comprises a return pipe in fluid communication between the liquid funnel system and the reservoir, the return pipe comprising an electrically insulated section configured to be electrically isolated from the plasma accelerator.

30. The apparatus of claim 29, wherein the electrically insulated section is oriented substantially vertically to provide drainage of liquid material into the reservoir.