Nuclear fusion reaction generation device, plasma generation device, nuclear fusion reaction generation method, and plasma generation method

Abstract

A nuclear fusion reaction generation device (1) comprises: at least a pair of electrodes (3, 3) that give a potential difference to an insulating liquid containing heavy water; a DC power supply (5) connected to the pair of electrodes (3, 3); and a plurality of carbon nanotubes (4) that have electrical conductivity and are dispersed in the liquid. Each of the carbon nanotubes (4) has a diameter of about 10 nm and a length of about 3 mm. The distance between the electrodes (3, 3) is 1 cm. The potential difference between the electrodes (3, 3) is 100 kV.

Description

Nuclear fusion reaction generating device, plasma generating device, nuclear fusion reaction generating method, and plasma generating method

[0001] The present disclosure relates to a nuclear fusion reaction generating device, a plasma generating device, a nuclear fusion reaction generating method, and a plasma generating method.

[0002] The necessary conditions for a nuclear fusion reaction are 10 8 The requirements are high temperatures of around 1000 K, sufficient density, and sufficient confinement time. Generally, the problems are the large energy and power required to generate high temperatures and the confinement of the resulting ultra-high pressure.

[0003] Fuel Plasma 10 8 When heated to K, the pressure increases in proportion to the temperature, and if this pressure is not contained, it expands and the reaction rate decreases (for example, even explosives 3 K temperature (at most 5000K) 8 Fusion plasma that can reach K is the 10th 5 At high temperatures, it emits high-energy thermal radiation and cools rapidly. This is because, according to the Stefan-Boltzmann law, if the object is a blackbody, the temperature is T 4 This is because the sun radiates heat with an energy proportional to the temperature of the central core. At high temperatures, the radiation is particularly strong, and as a result, even the sun, whose central temperature is 16 million K, can be considered a blackbody with a surface temperature of around 6000 K. 10 8 K is 10 of the solar surface per unit area. 16 This would be unrealistic, as it would emit more than twice the energy. However, since the optical depth of plasma on Earth is generally small, it would not be as intense, but it would emit thermal radiation (X-rays at high temperatures) commensurate with its temperature and cool rapidly. For this reason, it is not possible to heat it up over a long period of time, and it is necessary to make the optical depth of the plasma as small as possible.

[0004] 1g of heavy water fuel 10 8 To heat up to K in 1 second, you need to use ~10 9 J level, ~10 9This would require energy and power of around 1000 watts, which is not realistic. If DC power were used, even the power output of the Sakuma Frequency Converter Station, Japan's most powerful DC power source, would be insufficient. While the power output could be achieved with a pulsed power source, it would be difficult to achieve the above-mentioned amount of energy. Furthermore, with a practical energy multiplication factor, the output would be on par with that of a maximum conventional bomb. Therefore, a method for concentrating the heating of a small amount of fuel is essential for nuclear fusion ignition.

[0005] Some kind of confinement method is required to maintain density and promote the fusion reaction. Some method requires pressures that can easily compress both liquids and solids, and even ceramics must be confined to behave like a liquid. Various confinement methods are being considered, including magnetic confinement and inertial confinement.

[0006] In magnetic confinement, a small amount of fuel is heated in a concentrated manner by heating a dilute plasma (with a density that can be confined by a magnetic field) in a vacuum.

[0007] 10 8 To heat the plasma to K, it is sufficient to lower the potential difference by about 10 kV. However, because the plasma is thin, it needs to be confined for a relatively long time.

[0008] Plasma is basically treated as a particle flux, but in reality, plasma is a many-body system and a fluid (its behavior is chaotic), so at present it is not possible to confine plasma as desired.

[0009] Furthermore, it is difficult to reheat the plasma confined in space, and it is difficult to generate the commonly used high-power neutral particle beams and resonant microwaves efficiently and stably.

[0010] Inertial confinement involves shining a high-energy laser beam at a small fuel ball from all directions, thereby concentrating the heat on a small amount of fuel.

[0011] The high-temperature heated outer shell suddenly expands, compressing the center of the fuel to a pressure of 10 TPa (implosion), and adiabatic compression causes a pressure drop of 10 8The fuel is heated to K, resulting in a nuclear fusion reaction. Confinement is due to the inertia of the small mass of the fuel itself, so everything must be completed in an extremely short time.

[0012] However, it is difficult to heat and compress the fuel sphere uniformly because fluid dynamic instabilities make uniformity inherently difficult to achieve. This method requires not only confining the fuel but also actively compressing it, which can lead to rapid growth of instabilities and the tendency for the fuel sphere shell to rupture.

[0013] Furthermore, when using a laser for ignition, the low efficiency of conversion from electricity to laser becomes an issue. It is not enough to simply generate a laser; high energy must be packed into a very short period of time using techniques such as chirped pulse compression, which inevitably results in low energy efficiency.

[0014] Although a one-shot laser is not a problem, various issues must be overcome in order to continue the reaction continuously (such as the lifespan of the laser oscillator and the effects of materials accumulating in the furnace).

[0015] Another common problem with conventional containment systems is that neutrons and X-rays directly irradiate and damage the reactor walls. Therefore, appropriate measures must be taken to remove heat and prevent embrittlement and radioactivity. Systems using superconducting magnets can be particularly sensitive (e.g., neutron radiation can cause problems with the cooling medium), and the use of blankets increases maintenance costs due to replacement, increases low-level radioactive waste, and leads to the irreversible consumption of relatively scarce resources such as lithium through nuclear transmutation.

[0016] Another problem is the difficulty of procuring and handling tritium. Because the D-T reaction has the mildest reaction conditions for nuclear fusion, it is necessary to handle relatively large amounts of tritium, which is a rare and radioactive substance.

[0017] Patent Document 1 discloses that 1,000 carbon nanotubes, each about 3 mm in length, are connected in parallel between electrodes, and a pulsed voltage is applied to them to perform nuclear transmutation inside the system confined by the carbon nanotubes.

[0018] JP 2009-518646 A (Fig. 3, etc.)

[0019] However, in Patent Document 1, a pulse voltage of 200V for 200 nanoseconds is applied at a frequency of 10 kHz to 1000 carbon nanotubes with a total resistance of 200Ω (

[0070] ), and 200W for 200 nanoseconds, or 40,000 nanojoules, is shared among 1000 nanotubes, so that 40 nanojoules are applied per pulse. -12 Since it is on the order of grams, it is 40,000 J per gram, and the specific heat of graphite is about 2 J / g・K, so the calculated temperature rise is on the order of 10,000 K. Taking into account heat dissipation to the surroundings during heating and the effects of the pulse shape, it is expected that the temperature will not exceed 4,000 K. Since the pulse voltage is 10 kHz, there is a non-applied period of about 100 microseconds, during which time it cools down and the heat insulating layer collapses, so it is thought that the design does not destroy the carbon nanotubes as a whole.

[0020] Thus, in Patent Document 1, it is thought that the temperature reached will not exceed 4000K, which is the 10 8 It is not possible to achieve a temperature as high as 1000K.

[0021] The present disclosure has been made in light of these circumstances. 8 The object of the present invention is to provide a nuclear fusion reaction generating device, a plasma generating device, a nuclear fusion reaction generating method, and a plasma generating method that can realize high temperatures of about 1000K.

[0022] A nuclear fusion reaction generating device according to one embodiment of the present disclosure comprises at least a pair of electrodes that apply a potential difference to an insulating medium containing a nuclear fusion fuel, a power source connected to the pair of electrodes, and a plurality of conductive nanostructured materials dispersed in the medium, each of the nanostructured materials having a diameter of 1 nm or more and 100 nm or less and a length of 0.5 mm or more and 100 mm or less, the distance between the electrodes being 1 mm or more and 100 mm or less, and the potential difference being 10 kV or more and 1000 kV or less.

[0023] When a potential difference is applied between a pair of electrodes by supplying power from a power source, at least one conductive path is formed from one electrode to the other among the multiple nanostructured materials dispersed in the medium. Since the distance between the electrodes is 1 mm or more and 100 mm or less and the potential difference is 10 kV or more and 1000 kV or less, the formed conductive path is given sufficient energy to generate plasma. As a result, the conductive path formed by the nanostructured materials forms plasma filaments, and plasma can be generated. This allows 10 8 High temperatures of about 1000K can be achieved. Furthermore, since the medium contains a fusion fuel (e.g., heavy water, tritium, deuterium carbonate, etc.), it can be used as a fuel for a fusion reaction, causing a fusion reaction. Examples of nanostructured materials that can be used include nanotubes such as carbon nanotubes, nanowires such as copper nanowires, nanocoils, graphene nanoribbons, and conductive polymers. Each nanostructured material is preferably long and has ends.

[0024] A plasma generating device according to one embodiment of the present disclosure comprises at least a pair of electrodes that apply a potential difference to an insulating medium, a power source connected to the pair of electrodes, and a plurality of conductive nanostructured materials dispersed in the medium, each of the nanostructured materials having a diameter of 1 nm or more and 100 nm or less and a length of 0.5 mm or more and 100 mm or less, the distance between the electrodes being 1 mm or more and 100 mm or less, and the potential difference being 10 kV or more and 1000 kV or less.

[0025] When a potential difference is applied between a pair of electrodes by supplying power from a power source, at least one conductive path is formed from one electrode to the other among the multiple nanostructured materials dispersed in the medium. Since the distance between the electrodes is 1 mm or more and 100 mm or less and the potential difference is 10 kV or more and 1000 kV or less, the formed conductive path is given sufficient energy to generate plasma. As a result, the conductive path formed by the nanostructured materials forms plasma filaments, and plasma can be generated. This allows 10 8High temperatures of about 1000K can be achieved. Examples of nanostructured materials that can be used include nanotubes such as carbon nanotubes, nanowires such as copper nanowires, nanocoils, graphene nanoribbons, and conductive polymers. Each nanostructured material is preferably long and has ends.

[0026] A method for generating a nuclear fusion reaction according to one embodiment of the present disclosure is a method for generating a nuclear fusion reaction using at least a pair of electrodes that apply a potential difference to an insulating medium containing a nuclear fusion fuel, a power source connected to the pair of electrodes, and a plurality of conductive nanostructured materials dispersed in the medium, wherein each of the nanostructured materials has a diameter of 1 nm or more and 100 nm or less and a length of 0.5 mm or more and 100 mm or less, the distance between the electrodes is 1 mm or more and 100 mm or less, and the potential difference is 10 kV or more and 1000 kV or less.

[0027] A plasma generation method according to one embodiment of the present disclosure is a plasma generation method using at least a pair of electrodes that apply a potential difference to an insulating medium, a power source connected to the pair of electrodes, and a plurality of conductive nanostructured materials dispersed in the medium, wherein each of the nanostructured materials has a diameter of 1 nm or more and 100 nm or less and a length of 0.5 mm or more and 100 mm or less, the distance between the electrodes is 1 mm or more and 100 mm or less, and the potential difference is 10 kV or more and 1000 kV or less.

[0028] 10 8 High temperatures of about K can be achieved.

[0029] FIG. 1 is a schematic diagram showing a nuclear fusion reaction generating device according to Example 1 of an embodiment of the present disclosure. FIG. 2 is a schematic diagram corresponding to FIG. 1 and showing a state in which a switch is turned on. FIG. 3 is a diagram showing a calculation model of FIGS. 1 and 2. FIG. 4 is a schematic diagram showing an experimental device of Example 2. FIG. 5 is a photograph showing the needle electrode of FIG. 4. FIG. 6 is a photograph showing plasma light emission. FIG. 7 is a photograph showing a state in which metal is scattered around the needle electrode after plasma light emission. FIG. 8 is a photograph showing light emission by silver nanowires. FIG. 9 is a photograph showing light emission by carbon nanotubes.

[0030] An embodiment of the present disclosure will be described below. In the nuclear fusion reaction generating device according to this embodiment, the amount of fuel to be heated and the spatial size are minimized at the time of ignition. This minimizes the 10% reduction in the amount of fuel required for inertial fusion. -6 By heating only a certain amount of fuel in a certain space, rapid heating can be achieved with a realistic power output.

[0031] A high voltage sufficient to prevent total dielectric breakdown is applied to a conductive, nanostructured material (typically several tens of nanometers in diameter) dispersed in an insulating liquid (medium) serving as a nuclear fusion fuel (e.g., heavy water, tritium, deuterium carbonate, etc.; hereafter simply referred to as "fuel"). Examples of nanostructured materials that can be used include nanotubes such as carbon nanotubes, nanowires such as copper nanowires, nanocoils, graphene nanoribbons, and conductive polymers. The nanostructured material is elongated, with ends on both sides of its length, and the ratio of its length to its diameter is, for example, 1000 or more.

[0032] Partial breakdown causes current to flow through the nanostructured material, and if a sufficiently high potential gradient is applied, the current continues to flow due to self-inductance, even when the temperature of the nanostructured material reaches a temperature that would normally cause it to break down. A phase transition then generates tiny plasma filaments in the fuel. Because plasma is a good conductor, it can be heated by passing an electric current through it (Joule heating, an energy concentration method similar to that of a light bulb filament or a heating wire), and positive ions are heated by lowering the electromagnetic potential toward the negative pole.

[0033] In nuclear fusion, Sandia National Laboratories in the United States is conducting experiments using a Z machine to apply high voltage to a metal wire (diameter: about 0.1 mm) to generate plasma. -3 diameter, 10 -6 This generates very thin plasma filaments with a cross-sectional area of ​​about 1000mW. The plasma quickly diffuses due to the high pressure caused by the temperature rise, and it is thought that heat also diffuses quickly because the plasma is in contact with the liquid, but it can continue to exist like a plasma in a liquid.

[0034] The following selectivity occurs in the plasma filament: (1) Conductivity selectivity: Because the plasma is a good conductor, while the surrounding unionized fuel is an insulator, only the plasma portion is selectively heated by Joule heating.

[0035] (2) Confinement selectivity The plasma portion is confined by a magnetic field generated by the flow of electric current according to Ampere's law (magnetic confinement, Z-pinch). On the other hand, no confinement force acts on unionized fuel, so the unionized fuel, although heated and pressurized, separates the plasma from the surrounding fuel, making it difficult for the plasma heat to diffuse to the surroundings (for example, film boiling and burnout). In addition, the small surface area of ​​the plasma is also a factor that slows thermal diffusion.

[0036] The energy required to heat the plasma filament to the point where the above-mentioned fusion plasma is generated is small. This is because the amount of material contained in the plasma filament is small. If the surrounding fuel is absorbed during heating and the plasma filament becomes 100 nm thick (= 10 -5 cm), and a plasma filament with a length of 1 cm is formed, the amount of matter is 10 -10 It's only about g.

[0037] The radiation pressure due to thermal radiation is also important as a confinement force for plasma, especially at high temperatures. Because the surface area of ​​the plasma is small, the radiation pressure, which is proportional to the energy density of the radiation, is larger than in conventional methods.

[0038] However, there is no clear separation between ionized and non-ionized regions. At a certain temperature, individual particles have various velocities according to the Maxwellian distribution, so at temperatures between approximately 5,000 K and 20,000 K, ionized and non-ionized particles coexist (Saha's ionization formula). Because the degree of ionization determines electrical resistance, regions emerge where current flow becomes more difficult toward the periphery. Joule heating also occurs in this region, but because the Lorentz force pulls ionized particles toward the plasma filament, only high-energy particles are drawn into the peripheral region, resulting in cooling and preventing heat dissipation. Consequently, the higher the temperature and degree of ionization, the stronger the confinement force on partially ionized atoms such as carbon and oxygen (if fully ionized, the stronger the confinement force). (If fully ionized, the stronger the confinement force, almost the same as that of deuterium).

[0039] The surrounding fuel is heated by the plasma filament, creating a temperature gradient. When a temperature gradient occurs while the density remains constant, a pressure gradient is created, causing a flow of particles away from the plasma filament. Therefore, the surrounding cooler fuel is less likely to act against this flow and affect the plasma filament. When pressure equilibrium is achieved as a result of the flow, particle density is inversely proportional to temperature.

[0040] Although a confinement force acts on plasma filaments, it is generally difficult to confine them stably for long periods of time. Due to hydrodynamic instabilities such as the kink instability and the large fluctuations inherent in the mesoscopic region, plasma filaments take on complex shapes. Furthermore, if heating takes too long, the plasma filaments will absorb the surrounding fuel and become thicker, causing larger currents to flow and increasing the load on the power supply. Therefore, in order to reduce radiation losses, it is better to heat them at a relatively high rate.

[0041] Because the heat generation rate of plasma filaments is determined by the magnitude of the potential gradient, a high heat generation rate can be achieved even if the absolute applied voltage is not large, as long as the distance between the electrodes is small (for example, using an energy concentration method similar to that used in spark plugs). In this embodiment, if a readily available DC power supply is used and the voltage is set to 100 kV and the distance between the electrodes is set to 1 cm, the dielectric strength becomes 10 MV / m, which is close to the dielectric strength of water. Furthermore, under these conditions, deuterium ions can be provided with enough energy to initiate a nuclear fusion reaction by moving a few millimeters toward the negative electrode. Carbon ions and oxygen ions can be provided with sufficient energy even if they travel an even shorter distance.

[0042] The instability of plasma filaments is also beneficial for nuclear fusion ignition. Nanotubes and nanowires have a large L / D ratio (aspect ratio), so instabilities generate plasma of various shapes and conditions along the entire length of the plasma filament. Therefore, the probability that no self-igniting plasma will be generated when the current flow is stopped is low, and a high probability of self-igniting plasma generation can be expected.

[0043] Because the amount of material to be heated is small, it would be impractical if only the heated fuel were to undergo a nuclear fusion reaction. If the plasma filament is heated sufficiently, there is a certain probability that an auto-ignition region (a region where the energy generated internally by nuclear fusion is greater than the energy dissipated to the outside by radiation, etc.) will occur even after the current is turned off. Once the auto-ignition region occurs, it begins to expand, mainly due to alpha rays from the fusion plasma, because it is surrounded by liquid-density fuel. This expansion continues until the surrounding fuel is blown away and the pressure is sufficiently reduced (inertial confinement). Although the pressure of the plasma generated by heating is very high, the mass of the surrounding cold fuel is orders of magnitude greater, so it cannot be easily depressurized. This situation is similar to the detonation of an explosive.

[0044] On the other hand, in this embodiment, there are no strict restrictions on placing objects around the fuel (unlike laser fusion, etc.). Therefore, a tamper can be placed around the fuel to delay decompression and extend the duration of the fusion reaction. The tamper is heated by neutrons, etc., and the reaction caused by scattering to the surrounding area compresses the plasma, extending the time until decompression.

[0045] The tamper has the following roles: it confines the fusion plasma by inertia, it protects the reactor walls by absorbing neutrons and X-rays emitted from the fusion plasma, and it acts as a buffer to convert the extremely high temperatures of the fusion plasma into a manageable temperature for generating electricity. For this reason, it is desirable for the tamper to be a fluid that absorbs neutrons and X-rays (for example, a combination of molten metal and water, or water with heavy metals dispersed in it).

[0046] Regarding fuel density, if the fuel density is high, heat dissipation during heating is large, but the inertia acting after heating can be large. On the other hand, if the fuel density is low, heat dissipation during heating can be reduced, but the inertia acting after heating will be small. If the fuel is made into a supercritical fluid, the density of the fuel can be controlled arbitrarily, from a state where nanostructured materials are dispersed at or above liquid density to a state where nanostructured materials are suspended at a density lower than air, so ignition can be performed by adjusting the density to suit the purpose. The fuel density can also be changed during heating. For example, electrical heating can be started in a water vapor atmosphere at first, and cold water can be added during electrical current application.

[0047] The waveform of the voltage applied to the fuel may be DC, AC, or AC biased to DC, or may be any other waveform customized for ignition. This waveform is believed to determine the characteristics of fuel incorporation into the plasma filament.

[0048] The number of conductive paths that are simultaneously generated can be adjusted by adjusting the dispersion density of the nanostructured material and the contact area of ​​the electrodes with the fuel. If there are fewer conductive paths, the fuel can be heated to a higher temperature due to the concentrated energy. If there are more conductive paths, the paths attract each other due to the pinch force, and the fuel can be more tightly confined. Note that the distance between the opposing electrodes can be larger than that of a single carbon nanotube.

[0049] When using carbon nanotubes, fuel (such as deuterium, heavy water, or deuterium carbonate) can be placed inside the tube, or a substituent containing fuel can be bonded to the tube. Tritium or lithium can be used as an ignition aid. This is particularly effective when the fuel density is low.

[0050] Carbon nanotubes are easy to obtain with diameters of around 10 nm. Furthermore, due to their material and size, they have extremely low X-ray absorption, a small optical depth, and, according to Kirchhoff's law, low emissivity, resulting in low radiation loss. Metal nanowires, on the other hand, have the advantage of being easily heated due to their high charge density.

[0051] The ignition conditions can be controlled by the degree of dispersion of the nanostructured materials. By intentionally reducing the degree of dispersion and applying current to multiple nanostructured materials in an entangled state, a more diverse plasma-fuel configuration can be created as an ignition strategy.

[0052] Liquid deuterium is preferable as a fuel to increase the effective density and reaction probability. However, using heavy water or deuterium carbide to mix oxygen and carbon ions has its advantages. First, its high density allows for greater inertial confinement. Furthermore, when fully ionized, deuterium, oxygen, and carbon ions have similar specific charges, so they behave electromagnetically in the same way and move along similar trajectories when current is applied. However, when the current is stopped and thermal behavior begins, oxygen ions are eight times hotter and carbon ions are six times hotter than deuterium ions. Because the higher the temperature, the faster the diffusion rate. Therefore, when released from pinch confinement, oxygen and carbon ions first spread out, insulating and heating the deuterium ions, promoting the fusion reaction (the Soret effect is also involved).

[0053] Example 1 Example 1 of the above-described embodiment will be described below with reference to the drawings. FIG. 1 shows an outline of a nuclear fusion reaction generator 1 according to this example. As shown in the figure, the nuclear fusion reaction generator 1 is provided with a pair of electrodes 3, 3 so as to apply a potential difference to an insulating liquid 2. The electrodes 3, 3 are made of metal, for example, and the distance between the electrodes 3, 3 is 1 cm. The distance between the electrodes 3, 3 is set to a dimension greater than that of a single carbon nanotube 4.

[0054] A DC power supply (power supply) 5 is electrically connected to each of the electrodes 3, 3 via a switch 6. The DC power supply 5 is capable of applying a voltage of 100 kV to the electrodes 3, 3. Therefore, the electric field strength applied to the liquid 2 is 10 MV / m.

[0055] The liquid 2 is insulating and is water containing heavy water. A large number of carbon nanotubes 4 are dispersed in the liquid 2. The carbon nanotubes 4 have a diameter of about 10 nm and a length of about 3 mm.

[0056] The on / off operation of the switch 6 is controlled by a control unit. The control unit is composed of, for example, a central processing unit (CPU), random access memory (RAM), read-only memory (ROM), and a computer-readable storage medium. A series of processes for realizing various functions is stored in a storage medium, for example, in the form of a program. The CPU reads this program into the RAM and executes information processing and arithmetic operations to realize various functions. The program may be pre-installed in a ROM or other storage medium, provided in a state stored in a computer-readable storage medium, or distributed via wired or wireless communication means. Examples of computer-readable storage media include magnetic disks, magneto-optical disks, CD-ROMs, DVD-ROMs, and semiconductor memories.

[0057] As shown in Figure 2, when switch 6 is turned on by a command from the control unit, a DC voltage is applied between electrodes 3, 3, and an electric field strength of 10 MV / m is applied to liquid 2. As shown in Figure 2, carbon nanotubes 4 are dispersed in liquid 2, and there is a certain probability that the ends of each carbon nanotube 4 are sufficiently close to the ends of other nanotubes or to electrode 3. Dielectric breakdown then occurs between the ends of carbon nanotubes 4 or between the ends of carbon nanotubes 4 and electrodes 3, 3, causing current I to flow. Since the dielectric strength of pure water is approximately 60 MV / m, no current flows in other areas. The flowing current I is constant throughout the conductive path, but the current density is high near carbon nanotube 4 because it passes through a narrow region with a diameter on the order of 10 nm, resulting in high energy density and magnetic field strength.

[0058] Figure 3 shows a calculation model that is a simplification of Figures 1 and 2. To simplify the calculation, a model in which a plurality of carbon nanotubes 4 are connected in series between electrodes 3, 3 is considered.

[0059] The volume of a series of carbon nanotubes is 1×10 -6 x10 -6 = 10 -12 (cm3 ) For reference, the filament of a light bulb is 1 x 10 -2 x10 -2 = 10 -4 (cm 3 If the particle density of a carbon nanotube and a light bulb filament is about the same (the particle density of solids is not much different), when the same power is injected, the energy received by one particle of the carbon nanotube is 10 times that of the light bulb filament. 8 This doubles the heating rate, enabling high-speed heating.

[0060] If carbon nanotubes had the same density as graphite, they would be 10 -12 cm 3 The mass of a carbon nanotube is 2.2 x 10 -12 The specific heat capacity of plasma at constant pressure is about 100 J / g K at 20,000 K (reference value: https: / / www.jstage.jst.go.jp / article / jjtp1987 / 4 / 1 / 4_1_3 / _pdf / -char / ja Fig. 6). 8 The energy required to heat it to K is 10 -2 This is on the order of 1 J. Therefore, a voltage of 100 kV is sufficient to inject this energy.

[0061] Next, the nuclear fusion reaction generating device according to this embodiment generates 10 8 Let us consider what factors could be causing the inability to heat up to K. One possibility is that the current is interrupted during heating, particularly when the nanotubes evaporate. However, it can be said that the current is not interrupted due to self-inductance. Another example is a carbon arc lamp, where carbon vapor does not hinder conduction. It is possible that the thickness of the generated plasma increases rapidly, exceeding the power supply capacity before sufficient energy is injected. However, because the plasma has a small surface area and heat does not flow easily, and because a heat-shielding layer is formed by non-ionized gas, the plasma does not become too thick and exceed the power supply capacity. Even in actual liquid plasma, the phenomenon of a sudden increase in plasma thickness has not been confirmed.

[0062] Example 2 Next, an experimental example will be shown as Example 2 according to this embodiment. The purpose of this experimental example is to confirm that plasma is generated in water by applying a high electric field to an aqueous dispersion of nanostructured materials such as carbon nanotubes and silver nanowires. The following experimental results confirmed that plasma is generated in water for both the carbon nanotube dispersion and the silver nanowire dispersion.

[0063] Figure 4 shows the schematic configuration of the experimental apparatus 11. It is basically based on the calculation model shown in Figure 3. As shown in Figure 5, two needle electrodes 13 placed close to each other were used to generate a high electric field at a voltage that can be easily and safely handled. Each needle electrode 13 was immersed in a dispersion liquid 14 containing a nanostructured material. The needle electrodes 13 were connected to a power source 15 via a switch 16.

[0064] The dispersion liquids 14 used were a carbon nanotube dispersion in which carbon nanotubes were dispersed in water, and a silver nanowire dispersion in which silver nanowires were dispersed in water. The carbon nanotubes used were TDW0001 (length <100 μm, diameter 10-40 nm) from Hamamatsu Carbonix. The silver nanowires used were NovaWire-Ag-CI-A30 (length 30 μm, diameter 30 nm) from Novarials. The microscope camera used for observation was the L-KIT810 from HOZAN (spatial resolution ~1 μm, CMOS sensor). The power supply 15 used a Kikusui Electronics PMX35-3A (voltage accuracy ±3 mV) as the primary power supply, and a charge pump device (output capacitance 1000 μF) with 10 capacitors connected in series as the secondary power supply. The AC power supply used was Iwasaki Electric's H2.5TC1A41 (rated 210V mercury lamp ballast).

[0065] The following experiment was conducted using the experimental apparatus 11 described above. A sufficiently high electric field (approximately 2 MV / m, applied voltage of approximately 200 V) generated plasma in the dispersion 14 between the needle electrodes 13. The tip of the needle electrode also became plasma, and the plasma scattered along with a flash of light (Figures 6 and 7). These photographs show that the current increased runaway due to the negative resistance of the plasma, continuing to flow until it was limited by the amount of energy stored in the charge pump device. We also confirmed that plasma was generated in carbon nanotube and silver nanowire dispersions under similar conditions, but not in plain tap water. Although a warm-colored flash of light due to the plasma was observed, this flash was too strong and had a low color temperature, suggesting that it was due to the stainless steel needle electrodes becoming plasma, rather than the nanostructures themselves. Nevertheless, this demonstrates that plasma can be generated in water simply by passing electricity through a conductor in the water. Since molten and scattered metal can be seen around the electrode (Figure 7), it is clear that plasma was generated in the water at a temperature above the temperature at which the stainless steel of the electrode evaporates (near the boiling point of iron, 3134 K).

[0066] Next, we attempted to directly observe the plasma of the nanostructured material. However, rough calculations revealed that the visible thermal radiation emitted from nanosized plasma was too weak to be expected to be observable. It seemed that some form of luminescence was necessary for direct observation of plasma. Here, without any special device for luminescence, we observed blue luminescence, likely derived from nanosized plasma, for the silver nanowire dispersion by limiting the current with a choke coil (470 μH) and adjusting the concentration of dispersion 14 (Figure 8). Similarly, we observed white luminescence, likely derived from nanosized plasma, for the carbon nanotube dispersion by limiting the current with a choke coil (Figure 9).

[0067] We also attempted to generate plasma using AC, in order to enable repeated observation of nano-sized plasma, which can only be observed once with DC. Using the aforementioned mercury lamp ballast (rated at 210 V) as the power source 15 and a current-limiting resistor (10 kΩ) to prevent current runaway, we confirmed that plasma was generated quasi-steadily for both silver nanowires and carbon nanotubes. We also observed that the characteristic plasma generation gradually ceased over time for both nanostructured materials. This is thought to be because the nanostructured materials, once converted into plasma, cooled and extinguished near the zero-crossing point of the voltage, destroying the carbon nanotubes and silver nanowires. Once they were sufficiently reduced, plasma generation ceased.

[0068] From the above, the following can be inferred. The blue light seen in the silver nanowires is seen along the electric field lines, which is consistent with the silver nanowires aligning in the direction of the electric field lines due to electrostatic induction and becoming plasma. The absence of a significant red component due to the Hα line seen in normal in-liquid plasma in this light emission suggests that there is little water mixed into the plasma at this point, and that the nanostructures are being heated intensively.

[0069] On the other hand, the white light derived from carbon nanotubes appears more like a regular electric spark. The color of this white light is consistent with the color of carbon plasma seen in carbon arc lamps, suggesting that nano-sized plasma indeed emits light specific to its constituent materials. Furthermore, since different nanostructures exhibited different emissions with little in common in color and emission range, it is believed that these emissions are not due to anything other than the nanostructures (such as water or hydrogen and oxygen produced by decomposition), but rather to the plasma derived from the nanostructures themselves.

[0070] The effects of the present embodiment described above are as follows. When a potential difference is applied between a pair of electrodes by supplying power from a power source, at least one conductive path is formed from one electrode to the other among the multiple nanostructured materials dispersed in the liquid. Since the distance between the electrodes is about 1 cm and the potential difference is about 100 kV, the formed conductive path is given enough energy to generate plasma. As a result, the conductive path formed by the nanostructured materials forms plasma filaments, and plasma can be generated. This allows 10 8 It is possible to achieve high temperatures of about 1000 K. Furthermore, since the medium contains deuterium, it can be used as fuel for nuclear fusion reactions, and can generate nuclear fusion reactions.

[0071] Although the above-described embodiments and examples have been described as a nuclear fusion reaction generating device or a nuclear fusion reaction generating method, they can also be used as a plasma generating device or a plasma generating method. Furthermore, the carbon nanotubes 4 have been described as having a diameter of 10 nm, but they may have a diameter in the range of 1 nm to 100 nm and a length in the range of 0.5 mm to 100 mm. The distance between the electrodes 3 has been described as being 1 cm, but they may have a range of 1 mm to 100 mm. The potential difference between the electrodes 3 has been described as being 100 kV, but they may have a range of 10 kV to 1000 kV, and the electric field strength may be such that, together with the distance between the electrodes, they do not cause total dielectric breakdown.

[0072] REFERENCE SIGNS LIST 1 Nuclear fusion reaction generator 2 Liquid (medium) 3 Electrode 4 Carbon nanotube 5 Power supply 6 Switch 11 Experimental device 13 Needle electrode 14 Dispersion liquid 15 Power supply 16 Switch

Claims

1. A nuclear fusion reaction generating device comprising at least a pair of electrodes that apply a potential difference to an insulating medium containing a nuclear fusion fuel, a power source connected to the pair of electrodes, and a plurality of conductive nanostructured materials dispersed in the medium, wherein each of the nanostructured materials has a diameter of 1 nm or more and 100 nm or less and a length of 0.5 mm or more and 100 mm or less, the distance between the electrodes is 1 mm or more and 100 mm or less, and the potential difference is 10 kV or more and 1000 kV or less.

2. The nuclear fusion reaction generating device according to claim 1, wherein each of the nanostructured materials is elongated and has an end.

3. A plasma generating device comprising at least a pair of electrodes that apply a potential difference to an insulating medium, a power source connected to the pair of electrodes, and a plurality of conductive nanostructured materials dispersed in the medium, wherein each of the nanostructured materials has a diameter of 1 nm or more and 100 nm or less and a length of 0.5 mm or more and 100 mm or less, the distance between the electrodes is 1 mm or more and 100 mm or less, and the potential difference is 10 kV or more and 1000 kV or less.

4. The plasma generating device according to claim 3, wherein each of the nanostructured materials is elongated and has an end.

5. A nuclear fusion reaction generating method using at least a pair of electrodes that apply a potential difference to an insulating medium containing a nuclear fusion fuel, a power source connected to the pair of electrodes, and a plurality of conductive nanostructured materials dispersed in the medium, wherein each of the nanostructured materials has a diameter of 1 nm or more and 100 nm or less and a length of 0.5 mm or more and 100 mm or less, the distance between the electrodes is 1 mm or more and 100 mm or less, and the potential difference is 10 kV or more and 1000 kV or less.

6. The nuclear fusion reaction generating method according to claim 5, wherein each of the nanostructured materials is elongated and has an end.

7. A plasma generating method using at least a pair of electrodes that apply a potential difference to an insulating medium, a power source connected to the pair of electrodes, and a plurality of conductive nanostructured materials dispersed in the medium, wherein each of the nanostructured materials has a diameter of 1 nm or more and 100 nm or less and a length of 0.5 mm or more and 100 mm or less, the distance between the electrodes is 1 mm or more and 100 mm or less, and the potential difference is 10 kV or more and 1000 kV or less.

8. The plasma generation method according to claim 7, wherein each of the nanostructured materials is elongated and has an end portion.

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