Plasma confinement system and method of use

Abstract

An example plasma confinement system includes an inner electrode having a circular first end disposed on a longitudinal axis of the plasma confinement system, and an outer electrode at least partially surrounding the inner electrode. The outer electrode includes a solid electrically conductive shell and an electrically conductive material disposed on the solid electrically conductive shell and on the longitudinal axis of the plasma confinement system. The electrically conductive material has a melting point at 1 atmosphere in a range from 170 °C to 800 °C. Related plasma confinement systems and methods are also disclosed herein.

Description

[0001] Cross-reference to related applications

[0002] This application is a divisional application of Chinese invention patent application No. 201880034323.9, filed on June 7, 2018, entitled "Plasma Confinement System and Method of Use".

[0003] The aforementioned Chinese invention patent application claims the benefit of U.S. Provisional Patent Application No. 62 / 516,508, filed on June 7, 2017, the contents of which are incorporated herein by reference in their entirety. Background Technology

[0004] Unless otherwise stated herein, the materials described in this section are not prior art to the claims in this application and are not acknowledged as prior art by virtue of their inclusion in this section.

[0005] Nuclear fusion is the process of combining two nuclei. When two nuclei of elements with atomic numbers less than that of iron fuse, energy is released. The release of energy is due to the minute mass difference between the reactants and the products of the fusion reaction, and is expressed by ΔE = Δmc 2 The release of energy also depends on the strong, attractive nuclear forces between reactant nuclei overcoming the repulsive electrostatic forces between them.

[0006] The fusion reaction requiring the lowest plasma temperature occurs between deuterium (a hydrogen nucleus with one proton and one neutron) and tritium (a hydrogen nucleus with one proton and two neutrons). This reaction produces helium-4 nuclei and neutrons.

[0007] One method to achieve nuclear fusion is to excite a gas containing fusion reactants in a reaction chamber. The energized gas is then ionized into plasma. To achieve sufficient temperature and density for fusion to occur, the plasma needs to be confined. Summary of the Invention

[0008] A first aspect of this disclosure is a plasma confinement system comprising an internal electrode and an external electrode. The internal electrode has a circular first end disposed along the longitudinal axis of the plasma confinement system, and the external electrode at least partially surrounds the internal electrode. The external electrode comprises a solid conductive shell and a conductive material disposed on the solid conductive shell and along the longitudinal axis of the plasma confinement system. The conductive material has a melting point in the range of 170°C to 800°C at 1 atmosphere.

[0009] A second aspect of this disclosure is a method for operating a plasma confinement system. The plasma confinement system includes an internal electrode and an external electrode, the internal electrode having a circular first end disposed along the longitudinal axis of the plasma confinement system, and the external electrode at least partially surrounding the internal electrode. The method includes infusing gas into the plasma confinement system and applying a voltage between the internal and external electrodes via a power source, thereby converting at least a portion of the gas into Z-pinch plasma, the Z-pinch plasma flowing between (i) a solid conductive shell disposed on the external electrode and a conductive material along the longitudinal axis of the plasma confinement system and (ii) the circular first end of the internal electrode. The conductive material has a melting point in the range of 170°C to 800°C at 1 atmosphere. The method further includes removing a first liquid portion of the conductive material from the plasma confinement system. The first liquid portion of the conductive material is heated via reaction products of the Z-pinch plasma.

[0010] A third aspect of this disclosure is a plasma confinement system comprising an inner electrode, an intermediate electrode at least partially surrounding the inner electrode, and an outer electrode at least partially surrounding the intermediate electrode. The outer electrode comprises a solid conductive shell and a conductive material disposed on the solid conductive shell. The conductive material has a melting point in the range of 180°C to 800°C at 1 atmosphere.

[0011] A fourth aspect of this disclosure is a method for operating a plasma confinement system. The plasma confinement system includes an inner electrode, an intermediate electrode at least partially surrounding the inner electrode, and an outer electrode at least partially surrounding the intermediate electrode. The method includes allowing gas to flow into an acceleration region between the inner and intermediate electrodes, and applying a voltage between the inner and intermediate electrodes via a first power source to convert at least a portion of the gas into a plasma having a generally annular cross-section, the plasma flowing axially within the acceleration region toward a first end of the inner electrode and a first end of the outer electrode. The method further includes applying a voltage between the inner and outer electrodes via a second power source to establish a Z-pinch plasma flowing between (i) a conductive material disposed on a solid conductive shell of the outer electrode and (ii) the first end of the inner electrode. The conductive material has a melting point in the range of 180°C to 800°C at 1 atmosphere. The method further includes removing a first liquid portion of the conductive material from the plasma confinement system. The first liquid portion of the conductive material is heated by reaction products of the Z-pinch plasma.

[0012] When the terms “approximately” or “about” are used herein, it means that the feature, parameter, or value does not need to be precisely achieved, but may deviate or vary by a quantity that does not preclude the effect the feature is intended to provide, including, for example, tolerances, measurement errors, measurement accuracy limitations, and other factors known to those skilled in the art. In some instances disclosed herein, “approximately” or “about” means within + / - 5% of the value.

[0013] These and other aspects, advantages, and alternatives will become apparent to those skilled in the art upon reading the following detailed description and referring to the appropriate accompanying drawings. Furthermore, it should be understood that the present invention, along with the other descriptions and drawings provided herein, is intended to illustrate the invention by way of example only, and therefore many variations are possible. Attached Figure Description

[0014] Figure 1 This is a schematic cross-sectional view of a plasma confinement system according to an exemplary embodiment.

[0015] Figure 2 This is a schematic cross-sectional view of a plasma confinement system according to an exemplary embodiment.

[0016] Figure 3 This is a block diagram of a method for operating a plasma confinement system according to an exemplary embodiment.

[0017] Figure 4 Some aspects of a plasma confinement system and operating method according to an exemplary embodiment are shown.

[0018] Figure 5 Some aspects of a plasma confinement system and operating method according to an exemplary embodiment are shown.

[0019] Figure 6 Some aspects of a plasma confinement system and operating method according to an exemplary embodiment are shown.

[0020] Figure 7 Some aspects of a plasma confinement system and operating method according to an exemplary embodiment are shown.

[0021] Figure 8 Some aspects of a plasma confinement system and operating method according to an exemplary embodiment are shown.

[0022] Figure 9 Some aspects of a plasma confinement system and operating method according to an exemplary embodiment are shown.

[0023] Figure 10 This is a block diagram of a method for operating a plasma confinement system according to an exemplary embodiment.

[0024] Figure 11 Some aspects of a plasma confinement system and operating method according to an exemplary embodiment are shown.

[0025] Figure 12 Some aspects of a plasma confinement system and operating method according to an exemplary embodiment are shown.

[0026] Figure 13 Some aspects of a plasma confinement system and operating method according to an exemplary embodiment are shown.

[0027] Figure 14 Some aspects of a plasma confinement system and operating method according to an exemplary embodiment are shown.

[0028] Figure 15 Some aspects of a plasma confinement system and operating method according to an exemplary embodiment are shown.

[0029] Figure 16 Some aspects of a plasma confinement system and operating method according to an exemplary embodiment are shown. Detailed Implementation

[0030] This document discloses various embodiments of plasma confinement systems and methods of using them. Compared to existing systems and methods, the disclosed embodiments can promote increased plasma stability, stronger shear plasma flow, smaller Z-pinch plasma radius, higher magnetic fields, and / or higher plasma temperatures. Some of the disclosed embodiments also demonstrate independent control over plasma acceleration and plasma compression.

[0031] Additional features of some disclosed embodiments include one or more electrodes disposed with a liquid electrode material (e.g., disposed along the longitudinal axis of the plasma confinement system). The liquid electrode material can absorb and transfer heat from the plasma discharge, provide neutron shielding, generate additional tritium, provide additional vacuum pumping, and provide a tritium recovery medium. The use of liquid electrode material can help mitigate problems such as damage to (solid) electrodes due to the heat of the plasma discharge. The liquid electrode material can also circulate within the vacuum chamber (e.g., through a weir), such that its flow within the vacuum chamber has an azimuth and / or axial component.

[0032] Figure 1This is a schematic cross-sectional view of a plasma confinement system 100. The plasma confinement system 100 includes an internal electrode 102 having a circular first end 104 disposed on a longitudinal axis 106 (e.g., a cylindrically symmetric axis) of the plasma confinement system 100. The plasma confinement system 100 also includes an external electrode at least partially surrounding the internal electrode 102. The external electrode includes a solid conductive shell 108 and a conductive material 110 disposed on the solid conductive shell 108 and on the longitudinal axis 106 of the plasma confinement system 100. The conductive material 110 has a melting point in the range of 170°C to 800°C (e.g., 180°C to 550°C) at 1 atmosphere. In various embodiments, the conductive material 110 may be in eutectic form, alloy form, or a mixture of one or more of lithium, lead, or tin.

[0033] The internal electrode 102 typically takes the form of a conductive shell with a generally cylindrical body (e.g., formed of one or more of stainless steel, molybdenum, tungsten, or copper). The internal electrode 102 includes a first end 104 (e.g., a rounded end) and an opposing second end 126 (e.g., a generally disk-shaped end). The first end 104 may be formed of a carbon-based material such as graphite or carbon fiber, or of one or more of, for example, stainless steel, molybdenum, tungsten, or copper. In some embodiments, the internal electrode 102 has a coating on its outer surface comprising a conductive material having a melting point at 1 atmosphere in the range of 180°C to 800°C (e.g., 180°C to 550°C). In various embodiments, the conductive material may be in eutectic form, alloy form, or a mixture of one or more of lithium, lead, or tin. Alternatively, the conductive material may be in the form of elemental lithium, lead, or tin.

[0034] The plasma confinement system 100 also includes a feed mechanism 112 (e.g., an electromechanical system) configured to move the internal electrode 102 into or out of the plasma confinement system 100 along the longitudinal axis 106. During operation, the internal electrode 102 may be eroded by plasma discharge, and the feed mechanism 112 can be operated to feed the internal electrode 102, thereby maintaining the relative spacing between the internal electrode 102 and other components of the plasma confinement system 100.

[0035] The plasma confinement system 100 also includes a cooling system 114 (e.g., a heat exchanger) configured to cool the internal electrodes 102 during operation of the plasma confinement system 100.

[0036] The external electrode is typically in the form of a conductive (e.g., stainless steel) shell with a generally cylindrical body. The solid conductive shell 108 of the external electrode includes a solid conductive outer shell 132 and a solid inner shell 134 (e.g., formed of a conductive material or a high resistivity material such as silicon carbide), the solid inner shell being disposed within and in contact with the solid conductive outer shell 132. More specifically, the solid inner shell 134 includes an axial wall 136 and a radial wall 138, the axial wall at least partially surrounding the longitudinal axis 106 of the plasma confinement system 100 (e.g., partially surrounding the internal electrode 102), and the radial wall coupling the axial wall 136 to the solid conductive outer shell 132.

[0037] The external electrode includes a first end 120 and an opposing second end 122. A circular first end 104 of the internal electrode 102 lies between the first end 120 (e.g., a generally disk-shaped end) and the second end 122 (e.g., a generally annular end) of the external electrode. The radial wall 138 and the first end 120 of the external electrode form a pool region 140 within the plasma confinement chamber 100. The pool region 140 serves as a reservoir for a large quantity (e.g., liquid) of conductive material 110 within the plasma confinement chamber 100. As shown, the conductive material 110 can also be circulated along the end 148 of the axial wall 136 by pumps 150 and / or 156, as discussed in more detail below.

[0038] The outer electrode (i.e., the solid conductive shell 108 and the conductive material 110) surrounds most of the inner electrode 102. The inner electrode 102 and the outer electrode may be concentric and have radial symmetry with respect to the longitudinal axis 106.

[0039] The plasma confinement system 100 also includes a heat exchanger 142 configured to guide conductive material 110 from the heat exchanger 142 to a first port 144 in the pool region 140, and a second port 146 configured to guide conductive material 110 from the pool region 140 to the heat exchanger 142. The heat exchanger 142 is configured to receive the conductive material 110 heated within the plasma confinement system 100 via the second port 146, extract heat from the conductive material 110, and move (e.g., pump) the conductive material 110 back to the pool region 140 via the first port 144 for reheating by the fusion reaction occurring within the plasma confinement system 100. Figure 1 In the diagram, the first port 144 is shown above the second port 146; however, in other embodiments, the second port 146 may be above the first port 144. Those skilled in the art will recognize that ports 144 and 146 may have various relative positions in the various embodiments.

[0040] As described above, the axial wall 136 includes an end 148 facing the second end 122 of the external electrode. The plasma confinement system 100 also includes a first pump 150 configured to move conductive material 110 from the pool region 140 to a region 152 outside the axial wall 136 and separated from the pool region 140 by a radial wall 138. The first pump 150 is configured to move the conductive material 110 past the end 148 of the axial wall 136 to a region 154 inside the axial wall 136.

[0041] The plasma confinement system 100 also includes a second pump 156 configured to move conductive material 110 from pool region 140 to region 152, which is outside the axial wall 136 and separated from the pool region 140 by the radial wall 138.

[0042] The plasma confinement system 100 also includes a pump 170 (e.g., a turbomolecular pump) configured to pump air out of the plasma confinement system 100 such that the reference pressure within the plasma confinement system 100 is 10. -5 Up to 10 -8 Within the scope of the trust.

[0043] The plasma confinement system 100 also includes one or more gas ports 116 configured to direct gas (e.g., tritium, deuterium, helium-3, hydrogen, boron-containing gas, or borane) from a gas source 128 (e.g., a compressed gas canister) to an acceleration region 121, which is radially located between the inner electrode 102 and the outer electrode. The acceleration region 121 has a generally annular cross-section defined by the shapes of the inner electrode 102 and the solid conductive shell 108. Figure 1 As shown, one or more gas ports 116 are axially positioned between the first end 104 and the second end 126 of the internal electrode 102.

[0044] The plasma confinement system 100 also includes a power supply 118 configured to apply a voltage between an internal electrode 102 and an external electrode (e.g., a solid conductive shell 108). For example, the power supply 118 typically takes the form of a capacitor bank capable of storing up to 500 kJ or up to 3-4 MJ. The positive terminal of the power supply 118 may be coupled to the internal electrode 102 or optionally to the external electrode (e.g., the solid conductive shell 108).

[0045] The plasma confinement system 100 includes an assembly region 124 located within an external electrode between a first end 104 of an internal electrode 102 and a first end 120 of an external electrode. As described below, the plasma confinement system 100 is configured to maintain a Z-pinch plasma within the assembly region 124.

[0046] The plasma confinement system 100 also includes an insulator 117 located between a second end 122 of the outer electrode (e.g., a solid conductive shell 108) and the inner electrode 102 to maintain electrical insulation between the inner electrode 102 and the outer electrode. The insulator 117 (e.g., a ceramic material) typically has an annular cross-section.

[0047] Figure 2 This is a schematic cross-sectional view of plasma confinement system 200. Plasma confinement system 200 can have any of the features of plasma confinement system 100, the differences of which are described below. One difference between plasma confinement system 100 and plasma confinement system 200 is the presence of intermediate electrode 205 as part of plasma confinement system 200, as described below.

[0048] The plasma confinement system 200 includes an inner electrode 202, an intermediate electrode 205 (e.g., a generally annular electrode) at least partially surrounding the inner electrode 202, and an outer electrode at least partially surrounding the intermediate electrode 205. The outer electrode includes a solid conductive shell 208 and a conductive material 210 disposed on the solid conductive shell 208 (e.g., along a longitudinal axis 206). The conductive material 210 has a melting point in the range of 180°C to 800°C (e.g., 180°C to 550°C) at 1 atmosphere. In various embodiments, the conductive material 210 may be in eutectic form, alloy form, or a mixture of one or more of lithium, lead, or tin.

[0049] The internal electrode 202 typically takes the form of a conductive shell with a generally cylindrical body (e.g., formed of one or more of stainless steel, molybdenum, tungsten, or copper). The internal electrode 202 includes a first end 204 (e.g., a rounded end) and an opposing second end 226 (e.g., a generally disk-shaped end). The first end 204 may be formed of a carbon-based material such as graphite or carbon fiber, or of one or more of, for example, stainless steel, molybdenum, tungsten, or copper. In some embodiments, the internal electrode 202 has a coating on its outer surface comprising a conductive material having a melting point at 1 atmosphere in the range of 180°C to 800°C (e.g., 180°C to 550°C). In various embodiments, the conductive material may be in eutectic form, alloy form, or a mixture of one or more of lithium, lead, or tin.

[0050] The intermediate electrode 205 includes a first end 227 (e.g., a generally annular end) between a first end 220 of the outer electrode and a second end 222 of the outer electrode. The intermediate electrode 205 also includes a generally annular opposing second end 223.

[0051] The plasma confinement system 200 also includes a feeding mechanism 212 (e.g., an electromechanical system) configured to move the internal electrode 202 into or out of the plasma confinement system 200 along the longitudinal axis 206. During operation, the internal electrode 202 may be eroded by plasma discharge, and the feeding mechanism 212 can be operated to feed the internal electrode 202, thereby maintaining the relative spacing between the internal electrode 202 and other components of the plasma confinement system 200.

[0052] The plasma confinement system 200 also includes a cooling system 214 (e.g., a heat exchanger) configured to cool the internal electrodes 202 during operation of the plasma confinement system 200.

[0053] The external electrode is typically in the form of a conductive (e.g., stainless steel) shell with a generally cylindrical body. The solid conductive shell 208 of the external electrode includes a solid conductive outer shell 232 and a solid inner shell 234 (e.g., formed of a conductive material or a high resistivity material such as silicon carbide), the solid inner shell being disposed within and in contact with the solid conductive outer shell 232. More specifically, the solid inner shell 234 includes an axial wall 236 and a radial wall 238, the axial wall at least partially surrounding the longitudinal axis 206 of the plasma confinement system 200 (e.g., partially surrounding the internal electrode 202), and the radial wall coupling the axial wall 236 to the solid conductive outer shell 232.

[0054] The external electrode includes a first end 220 and an opposing second end 222. A circular first end 204 of the internal electrode 202 lies between the first end 220 (e.g., a generally disk-shaped end) and the second end 222 (e.g., a generally circular or annular end) of the external electrode. The radial wall 238 and the first end 220 of the external electrode form a pool region 240 within the plasma confinement chamber 200. The pool region 240 serves as a reservoir for a large quantity (e.g., liquid) of conductive material 210 within the plasma confinement chamber 200. As shown, the conductive material 210 can also be circulated through the end 248 of the axial wall 236 by pumps 250 and / or 256, as discussed in more detail below.

[0055] The outer electrode (i.e., the solid conductive shell 208 and the conductive material 210) surrounds a large portion of the inner electrode 202. The inner electrode 202 and the outer electrode may be concentric and have radial symmetry with respect to the longitudinal axis 206.

[0056] The plasma confinement system 200 also includes a heat exchanger 242 configured to guide conductive material 210 from the heat exchanger 242 to a first port 244 in the pool region 240, and a second port 246 configured to guide conductive material 210 from the pool region 240 to the heat exchanger 242. The heat exchanger 242 is configured to receive the conductive material 210 heated within the plasma confinement system 200 via the second port 246, extract heat from the conductive material 210, and move (e.g., pump) the conductive material 210 back to the pool region 240 via the first port 244 for reheating through the fusion reaction occurring within the plasma confinement system 200. Figure 2 In this diagram, the first port 244 is shown above the second port 246; however, in other embodiments, the second port 246 may be above the first port 244. Those skilled in the art will recognize that ports 244 and 246 may have various relative positions in the various embodiments.

[0057] As described above, the axial wall 236 includes an end 248 facing the second end 222 of the external electrode. The plasma confinement system 200 also includes a first pump 250 configured to move conductive material 210 from the pool region 240 to a region 252 outside the axial wall 236 and separated from the pool region 240 by a radial wall 238. The first pump 250 is configured to circulate the conductive material 210 through the end 248 of the axial wall 236 to a region 254 inside the axial wall 236.

[0058] The plasma confinement system 200 also includes a second pump 256 configured to move conductive material 210 from pool region 240 to region 252, which is outside the axial wall 236 and separated from the pool region 240 by the radial wall 238.

[0059] The plasma confinement system 200 also includes a pump 270 (e.g., a turbomolecular pump) configured to pump air out of the plasma confinement system 200 such that the reference pressure within the plasma confinement system 200 is 10 -5 Up to 10 -8 Within the scope of the trust.

[0060] The plasma confinement system 200 also includes one or more gas ports 216 configured to direct gas (e.g., tritium, deuterium, helium-3, hydrogen, boron-containing gas, or borane) from a gas source 228 (e.g., a compressed gas canister) into an acceleration region located radially between the inner electrode 202 and the intermediate electrode 205. The acceleration region has a generally annular cross-section defined by the shapes of the inner electrode 202 and the intermediate electrode 205. Figure 2As shown, one or more first gas ports 216 are axially positioned between the first end 204 of the internal electrode 202 and the second end 226 of the internal electrode 102.

[0061] The plasma confinement system 200 also includes a power supply 218 configured to apply a voltage between the internal electrode 102 and the intermediate electrode 205. For example, the power supply 218 typically takes the form of a capacitor bank capable of storing up to 500 kJ or up to 3-4 MJ. The positive terminal of the power supply 218 may be coupled to the internal electrode 102 or optionally to the intermediate electrode 205.

[0062] The plasma confinement system 200 also includes a power supply 219 configured to apply a voltage between the internal electrode 102 and an external electrode (e.g., the solid conductive shell 208). For example, the power supply 219 typically takes the form of a capacitor bank capable of storing up to 500 kJ or up to 3-4 MJ. The positive terminal of the power supply 219 may be coupled to the internal electrode 102 or optionally to the external electrode (e.g., the solid conductive shell 208).

[0063] The plasma confinement system 200 includes an assembly region 224 located within an external electrode between a first end 204 of an internal electrode 202 and a first end 220 of an external electrode. As described below, the plasma confinement system 200 is configured to maintain a Z-pinch plasma within the assembly region 224.

[0064] The plasma confinement system 200 also includes an insulator 217 located between the second end 223 of the intermediate electrode 205 and the inner electrode 202 to maintain electrical insulation between the inner electrode 202 and the intermediate electrode 205. The insulator 217 (e.g., a ceramic material) typically has an annular cross-section.

[0065] The plasma confinement system 200 also includes an insulator 229 located between the solid conductive shell 208 and the intermediate electrode 205 to maintain electrical insulation between the solid conductive shell 208 and the intermediate electrode 205. The insulator 229 (e.g., a ceramic material) typically has an annular cross-section.

[0066] Figure 3 This is a block diagram of a method 300 for operating a plasma confinement system (e.g., plasma confinement system 100). The plasma confinement system includes an internal electrode and an external electrode, the internal electrode having a circular first end disposed on the longitudinal axis of the plasma confinement system, and the external electrode at least partially surrounding the internal electrode. Figures 4 to 9 Some aspects of the method 300 described below are illustrated. Although Figures 4 to 9 The longitudinal axis 106 of the horizontally aligned plasma confinement system 100 is shown, but in practice, the longitudinal axis 106 will usually be vertically aligned.

[0067] In block 302, method 300 includes allowing gas to flow into a plasma confinement system.

[0068] For example, such as Figure 4 As shown, one or more gas ports 116 can guide gas 310 (e.g., one or more of tritium, deuterium, helium-3, hydrogen, boron-containing gas or borane) into an acceleration region 121 between an inner electrode 102 and an outer electrode (e.g., a solid conductive shell 108), the outer electrode generally surrounding the inner electrode 102. Figure 4 This shows an initial amount of gas 310 entering the acceleration region 121, and... Figure 5 An additional amount of gas 310 is shown entering the acceleration zone 121 afterward.

[0069] After the gas 310 is circulated and before the voltage between the internal electrode 102 and the external electrode (e.g., the solid conductive shell 108) is applied via the power source 118, the gas pressure adjacent to one or more gas ports 116 in the acceleration region 121 may be in the range of 1,000 to 5,800 Torr (e.g., 5,450 to 5,550 Torr).

[0070] In block 304, method 300 includes applying a voltage between an internal electrode and an external electrode via a power source, thereby converting at least a portion of the gas into a Z-pinch plasma, the Z-pinch plasma flowing between (i) a solid conductive shell disposed on the external electrode and a conductive material along the longitudinal axis of the plasma confinement system and (ii) a circular first end of the internal electrode. The conductive material has a melting point in the range of 170°C to 800°C (e.g., 180°C to 550°C) at 1 atmosphere.

[0071] For example, refer to Figures 6 to 9 The power supply 118 can apply a voltage between the internal electrode 102 and the external electrode (e.g., the solid conductive shell 108) to convert at least a portion of the gas 310 into Z-pinch plasma 318 (see [link to power supply]). Figures 8 to 9 Z-pinch plasma flows between (i) the solid conductive shell 108 of the external electrode and the conductive material 110 on the longitudinal axis 106 of the plasma confinement system 100 and (ii) the circular first end 104 of the internal electrode 102.

[0072] For example, power supply 118 can apply a voltage between internal electrode 102 and solid conductive shell 108, thereby converting at least a portion of gas 310 into plasma 316 having a generally annular cross-section (see [link]). Figures 6 to 9 Due to the magnetic field generated by its own current, plasma 316 can flow axially within acceleration region 121 towards the first end 104 of the inner electrode 102 and the first end 120 of the outer electrode, as... Figures 6 to 9They are shown in sequence.

[0073] like Figure 8 and Figure 9 As shown, when plasma 316 moves beyond acceleration region 121, Z-pinch plasma 318 is established in assembly region 124 within external electrode, between (i) the conductive material 110 disposed on solid conductive shell 108 of external electrode and on longitudinal axis 106 of plasma confinement system 100 and (ii) the circular first end 104 of internal electrode 102.

[0074] Z-pinch plasma 318 can exhibit shear axial flow with radii between 0.1 mm and 5 mm, ion temperatures between 900 eV and 50,000 eV, electron temperatures above 500 eV (e.g., up to 50,000 eV), and ion number densities greater than 1 × 10⁻⁶. 23 ions / m 3 Electron number density greater than 1×10 23 Electronics / m 3 The magnetic field exceeds 8 T, and / or can be stable for at least 10 μs.

[0075] At block 306, method 300 includes removing a first liquid portion of the conductive material from the plasma confinement system. The first liquid portion of the conductive material is heated by reaction products of the Z-pinch plasma (e.g., neutrons and other high-energy particles).

[0076] Heat exchanger 142 can receive (e.g., pump) a portion of the conductive material 110 heated within the plasma confinement system 100 via a second port 146, extract heat from the conductive material 110, and move (e.g., pump) the conductive material 110 back into the pool region 140 via a first port 144 to be reheated by the fusion reaction occurring within the plasma confinement system 100. The conductive material 110 is typically heated (e.g., melted) into a liquid state using (e.g., electrically heated) heating elements disposed within the plasma confinement system 100 before a plasma discharge is formed within the plasma confinement system 100.

[0077] The plasma confinement system 100 includes a feed mechanism 112 (e.g., an electromechanical system) that can move an internal electrode 102 into or out of the plasma confinement system 100 along a longitudinal axis 106. During operation, the internal electrode 102 may be eroded by plasma discharge, and the feed mechanism 112 can be operated to feed the internal electrode 102, thereby maintaining the relative spacing between the internal electrode 102 and other components of the plasma confinement system 100.

[0078] Additionally, pumps 150 and 156 can move or circulate the conductive material 110 through the external electrodes (e.g., through the solid conductive shell 108), thereby allowing different portions of the conductive material 110 to absorb current and / or heat from the Z-pinch plasma over time (e.g., at the longitudinal axis 106). During operation of the plasma confinement system 100, a large portion or all of the conductive material 110 will typically be in a liquid state.

[0079] In some embodiments, pumps 150 and 156 move the conductive material 110 such that the conductive material 110, which has moved past the external electrodes (e.g., past the solid conductive shell 108), moves relative to the longitudinal axis 106 of the plasma confinement system 100 in the azimuth direction (e.g., moving into and / or out of the page) and / or axial direction.

[0080] More specifically, pump 150 or 156 can move conductive material 110 from pool region 140 to region 152, which is outside the axial wall 136 and separated from pool region 140 by radial wall 138. Additionally, pump 150 or 156 can move conductive material 110 through end 148 of axial wall 136 to region 154 inside axial wall 136 and back towards pool region 140.

[0081] In various embodiments, the voltage applied between the inner electrode 102 and the outer electrode (e.g., the solid conductive shell 108) is in the range of 2 kV to 30 kV. The voltage applied between the inner electrode and the outer electrode (e.g., the solid conductive shell 108) can result in a radial electric field in the range of 30 kV / m to 500 kV / m.

[0082] In some embodiments, the radius of the Z-pinch plasma 318 is between 0.1 mm and 5 mm, the ion temperature is between 900 eV and 50,000 eV, and the electron temperature is above 500 eV (e.g., up to 50,000 eV). The Z-pinch plasma 318 can have a radius greater than 1 × 10⁻⁶. 23 ions / m 3 The ion number density is greater than 1×10 23 Electronics / m 3 The electron number density is high, and it can exhibit shear flow with magnetic fields exceeding 8 T. Z-pinch plasma 318 can exhibit stability of at least 10 μs.

[0083] In some embodiments, the reaction products of the Z-pinch plasma 318 include neutrons. Thus, during operation of the plasma confinement system 100, neutrons and a portion of the conductive material 110 can be consumed to generate additional tritium fuel recovered at the heat exchanger 142. The reactive properties of the conductive material 110 can also be used to reduce the reference pressure within the plasma confinement system 100 by trapping vapor particles.

[0084] Some implementations include controlling the thickness of the conductive material 110 on the solid conductive shell 108 by adjusting the rate at which the conductive material 110 is moved from the heat exchanger 142 into the pool region 140, or by adjusting the rate at which the conductive material 110 is moved from the pool region 140 into the heat exchanger 142. Increasing the rate at which the conductive material 110 flows into the pool region 140 generally increases the thickness of the conductive material 110 on the solid conductive shell 108. Increasing the rate at which the conductive material 110 flows out of the pool region 140 into the heat exchanger 142 generally decreases the thickness of the conductive material 110 on the solid conductive shell 108.

[0085] Figure 10 This is a block diagram of a method 1000 for operating a plasma confinement system (e.g., plasma confinement system 200). The plasma confinement system includes an inner electrode, an intermediate electrode at least partially surrounding the inner electrode, and an outer electrode at least partially surrounding the intermediate electrode. Figures 11 to 16 Some aspects of the method 1000 described below are illustrated. Although Figures 11 to 16 The longitudinal axis 206 of the horizontally aligned plasma confinement system 200 is shown, but in practice, the longitudinal axis 206 will usually be vertically aligned.

[0086] At block 1002, method 1000 includes allowing gas to flow into an acceleration region between the inner electrode and the intermediate electrode.

[0087] For example, such as Figure 11 As shown, one or more gas ports 216 can guide gas 310 (e.g., one or more of tritium, deuterium, helium-3, hydrogen, boron-containing gas or borane) to an acceleration region 221 between an inner electrode 202 and an intermediate electrode 205, the intermediate electrode portion surrounding the inner electrode 202. Figure 11 This shows an initial amount of gas 310 entering the acceleration region 221, and... Figure 12 An additional amount of gas 310 is shown entering the acceleration zone 221 afterward.

[0088] After the gas 310 is circulated and before the voltage between the internal electrode 202 and the intermediate electrode 205 is applied via the power supply 218, the gas pressure adjacent to one or more gas ports 216 in the acceleration region 221 may be in the range of 1,000 to 5,800 Torr (e.g., 5,450 to 5,550 Torr).

[0089] At block 1004, method 1000 includes applying a voltage between an inner electrode and an intermediate electrode via a first power source, thereby converting at least a portion of the gas into a plasma having a generally annular cross section, the plasma flowing axially toward a first end of the inner electrode and a first end of the outer electrode within an acceleration region.

[0090] For example, refer to Figures 11 to 14 Power supply 218 can apply a voltage between the inner electrode 202 and the intermediate electrode 205, thereby converting at least a portion of the gas 310 into plasma 316 having a generally annular cross-section. Plasma 316 can flow axially within acceleration region 221 towards the first end 204 of the inner electrode 202 and the first end 220 of the outer electrode. Due to the magnetic field generated by its own current, plasma 316 can flow axially within acceleration region 121 towards the first end 204 of the inner electrode 202 and the first end 220 of the outer electrode, such as... Figures 11 to 14 They are shown in sequence.

[0091] At block 1006, method 1000 includes applying a voltage between an inner electrode and an outer electrode via a second power source to establish a Z-pinch plasma, the Z-pinch plasma flowing between (i) a conductive material disposed on a solid conductive shell of the outer electrode and (ii) a first end of the inner electrode. The conductive material has a melting point at 1 atmosphere in the range of 180°C to 800°C (e.g., 180°C to 550°C).

[0092] For example, refer to Figure 15 and Figure 16 The power source 219 can apply a voltage between the internal electrode 202 and the external electrode (e.g., the solid conductive shell 208) to establish a Z-pinch plasma 318, which flows between (i) the conductive material 210 disposed on the solid conductive shell 208 of the external electrode and (ii) the first end 204 of the internal electrode 202. The conductive material 210 has a melting point in the range of 180°C to 800°C (e.g., 180°C to 550°C) at 1 atmosphere.

[0093] like Figure 15 and Figure 16As shown, when plasma 316 moves beyond acceleration region 221, Z-pinch plasma 318 is established in assembly region 224 within external electrode, between (i) the conductive material 210 disposed on solid conductive shell 208 of external electrode and on longitudinal axis 206 of plasma confinement system 200 and (ii) the circular first end 204 of internal electrode 202.

[0094] Z-pinch plasma 318 can exhibit shear axial flow with radii between 0.1 mm and 5 mm, ion temperatures between 900 eV and 50,000 eV, electron temperatures above 500 eV (e.g., up to 50,000 eV), and ion number densities greater than 1 × 10⁻⁶. 23 ions / m 3 Electron number density greater than 1×10 23 Electronics / m 3 The magnetic field exceeds 8 T, and / or can be stable for at least 10 μs.

[0095] At block 1008, method 1000 includes removing a first liquid portion of a conductive material from the plasma confinement system. The first liquid portion of the conductive material is heated via reaction products of the Z-pinch plasma.

[0096] For example, refer to Figure 2 Heat exchanger 242 can receive (e.g., pump) a portion of the conductive material 210 heated within the plasma confinement system 200 via a second port 246, extract heat from the conductive material 210, and move (e.g., pump) the conductive material 210 back into the pool region 240 via a first port 244 to be reheated by the fusion reaction occurring within the plasma confinement system 200. Before a plasma discharge is formed within the plasma confinement system 200, the conductive material 210 is typically heated (e.g., melted) into a liquid state using (e.g., electrically heated) heating elements disposed within the plasma confinement system 200.

[0097] The plasma confinement system 200 includes a feeding mechanism 212 (e.g., an electromechanical system) that can move the internal electrode 202 into or out of the plasma confinement system 200 along the longitudinal axis 206. During operation, the internal electrode 202 may be eroded by plasma discharge, and the feeding mechanism 212 can be operated to feed the internal electrode 202, thereby maintaining the relative spacing between the internal electrode 202 and other components of the plasma confinement system 200.

[0098] Additionally, pumps 250 and 256 can move or circulate the conductive material 210 through the external electrodes (e.g., through the solid conductive shell 208), allowing different portions of the conductive material 210 to absorb Z-pinch plasma current and / or heat over time (e.g., at the longitudinal axis 206). During operation of the plasma confinement system 200, a large portion or all of the conductive material 210 will typically be in a liquid state.

[0099] In some embodiments, pumps 250 and 256 move conductive material 210 such that the conductive material 210, which moves past the external electrodes (e.g., past the solid conductive shell 208), moves relative to the longitudinal axis 206 of the plasma confinement system 100 in the azimuth direction (e.g., moving into and / or out of the page) and / or axial direction.

[0100] More specifically, pump 250 or 256 can move conductive material 210 from pool region 240 to region 252, which is outside the axial wall 236 and separated from pool region 240 by radial wall 238. Additionally, pump 250 or 256 can move conductive material 210 through end 248 of axial wall 236 to region 254 inside axial wall 236 and back towards pool region 240.

[0101] In various embodiments, the voltage applied between the internal electrode 202 and the external electrode (e.g., the solid conductive shell 108) or between the internal electrode 202 and the intermediate electrode 205 is in the range of 2 kV to 30 kV. The applied voltage may result in an electric field in the range of 30 kV / m to 500 kV / m.

[0102] In some embodiments, the radius of the Z-pinch plasma 318 is between 0.1 mm and 5 mm, the ion temperature is between 900 eV and 50,000 eV, and the electron temperature is above 500 eV (e.g., up to 50,000 eV). The Z-pinch plasma 318 can have a radius greater than 1 × 10⁻⁶. 23 ions / m 3 The ion number density is greater than 1×10 23 Electronics / m 3 The electron number density is high, and it can exhibit shear flow with magnetic fields exceeding 8 T. Z-pinch plasma 318 can exhibit stability of at least 10 μs.

[0103] In some embodiments, the reaction products of the Z-pinch plasma 318 include neutrons. Thus, during operation of the plasma confinement system 200, neutrons and a portion of the conductive material 210 can be consumed to generate additional tritium fuel recovered at the heat exchanger 242. The reactive properties of the conductive material 210 can also be used to reduce the reference pressure within the plasma confinement system 200 by trapping vapor particles.

[0104] Some implementations include controlling the thickness of the conductive material 210 on the solid conductive shell 208 by adjusting the rate at which the conductive material 210 is moved from the heat exchanger 242 into the pool region 240, or by adjusting the rate at which the conductive material 210 is moved from the pool region 240 into the heat exchanger 242. Increasing the rate at which the conductive material 210 flows into the pool region 240 generally increases the thickness of the conductive material 210 on the solid conductive shell 208. Increasing the rate at which the conductive material 210 flows out of the pool region 240 into the heat exchanger 242 generally decreases the thickness of the conductive material 210 on the solid conductive shell 208.

[0105] While various exemplary aspects and implementations have been disclosed herein, other aspects and implementations will be apparent to those skilled in the art. The various exemplary aspects and implementations disclosed herein are for illustrative purposes and are not intended to be limiting, wherein the true scope and spirit are indicated by the following claims.

Claims

1. A plasma confinement system, comprising: External electrode, the external electrode comprising a conductive material; A pumping system configured to circulate the conductive material through the external electrode when the conductive material is in a liquid state; An internal electrode, wherein a first end of the internal electrode is between a first end of the external electrode and a second end of the external electrode, and wherein the internal electrode and the external electrode are radially symmetrical with respect to the longitudinal axis of the plasma confinement system; and A power source configured to apply a voltage between the internal electrode and the external electrode to establish a Z-pinch plasma with shear axial flow between the internal electrode and the external electrode.

2. The plasma confinement system according to claim 1, wherein, The conductive material includes alloys.

3. The plasma confinement system according to claim 1, wherein, The internal electrode comprises a carbon-based material or one or more of stainless steel, molybdenum, tungsten, or copper.

4. The plasma confinement system of claim 1 further includes one or more gas ports axially positioned between the first end of the internal electrode and a second end of the internal electrode opposite to the first end of the internal electrode.

5. The plasma confinement system according to claim 1, further comprising a ceramic insulator between the second ends of the internal electrode and the external electrode.

6. The plasma confinement system according to claim 1, wherein, The internal electrode and the external electrode are concentric.

7. The plasma confinement system according to claim 1, wherein, The outer electrode surrounds most of the volume occupied by the inner electrode.

8. The plasma confinement system according to claim 1, wherein, The outer electrode surrounds the inner electrode.

9. The plasma confinement system according to claim 1, wherein, The internal electrode and the external electrode each have a cylindrical body.

10. The plasma confinement system according to claim 1, wherein, The first end of the external electrode is opposite to the second end of the external electrode.

11. The plasma confinement system according to claim 1, wherein, An acceleration region with an annular cross-section is formed in the volume between the inner electrode and the outer electrode in the radial direction.

12. The plasma confinement system according to claim 1, wherein, The power source is configured to maintain Z-pinch plasma in an assembly region formed in a cylindrical volume within the external electrodes.

13. The plasma confinement system of claim 1, further comprising a pump configured to pump air out of the plasma confinement system such that the basic pressure within the plasma confinement system is 10... -5 To and 10 -8 Within the scope of the trust.

14. The plasma confinement system according to claim 1, wherein, The shearing axial flow is radially sheared relative to the longitudinal axis.

15. A method for operating a plasma confinement system according to any one of claims 1 to 14, the method comprising: A voltage is applied between the internal electrode and the external electrode via the power source; and The first liquid portion of the conductive material is removed from the plasma confinement system.

16. The method according to claim 15, wherein, The voltage applied between the internal electrode and the external electrode is in the range of 2kV to 30kV.

17. The method according to claim 15, wherein, The Z-pinch plasma exhibits ion temperatures between 900 eV and 50,000 eV.

18. The method according to claim 15, wherein, The Z-pinch plasma exhibits an electron temperature greater than 500 eV.

19. The method according to claim 15, wherein, The Z-pinch plasma is stable for at least 10 μs.

20. The method of claim 15, wherein, The radius of the Z-pinch plasma is between 0.1 mm and 5 mm.

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