JPS6166400A - Plasma heating antenna - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a nuclear fusion device, and particularly relates to antenna C which heats the plasma by injecting a high frequency current into the plasma.

[Technical background of the invention]

A conventional nuclear fusion device will be explained with reference to FIGS. 1 and 2. The first factor is a partially cut away perspective factor, which is the 2ti vacuum vessel in Figure 1. This vacuum container 2 is a torus-shaped container that confines the plasma 4 inside and maintains a high vacuum. A 5I nib blanket 6 is integrally provided on the inner surface of the vacuum vessel 2 so as to surround the plasma. The blanket 6 contains lithium as a nitritium breeding material and is provided with a coolant flow path for cooling the lithium. And blanket 6
The high-energy neutrons emitted from the plasma 4 react with lithium to generate tritium, and the thermal energy generated at this time is extracted to the outside by the coolant flowing in the coolant flow path. ing.

Further, the circumference C of the vacuum container 2 is a toroidal coil 8° provided in the toroidal direction of the vacuum container 2, and a main voloidal coil t o provided in the voloidal direction of the vacuum container 2.
+ M'J holoidal coil 12° and magnetic limiter coil 14 are provided. 1 @J's toroidal coil 81 Both poloidal coils 10.12 form a magnetic field generating coil ◎The heat output limiter coil 14 is located inside the vacuum vessel 2. 0 which restricts the shape of the plasma 4 with magnetic lines of force, and each of these coils and the vacuum g Fp 2
C; placed on the kl stand 16.

A rectangular iron core 18 is provided which passes through the hollow part of the torus-shaped vacuum vessel 2 from top to bottom and surrounds the vacuum vessel 2 and each coil.The circumference of this iron core 18≦2 is the current transformer coil 2o. is wound, and this current transformer coil 20
．． Tetsushin III.

The magnetic field generating coil C2 forms a current transformer, and the magnetic field generating coil C2 is configured to pass a high current and generate a magnetic field inside the vacuum vessel 2.The plasma 4 inside the vacuum vessel 2 is generated by the magnetic field. It is designed to be heated by Joule current and heated to a high temperature.

As shown in FIG. 2, a shield 22 is generally provided on the outer peripheral surface of the vacuum container 2 to surround the vacuum container 2 and to prevent radiation from leaking outside. 0 Further, a neutral particle injection device 23 and a secondary heating device such as a high frequency heating device (not shown) are arranged around the vacuum container 2. Neutral beam injection is performed via secondary heating tubes 24 provided at multiple locations C on the surface.
on: NBI) to further heat the plasma 20. In addition, 26 is an exhaust pipe, which communicates with a vacuum exhaust device (not shown) and connects the vacuum container 2.
The high-frequency heating device is configured to maintain a high vacuum C2 inside the high-frequency heating device.
ncy: RF) It is a device that performs heating and is shown in the second factor C, vacuum container 2 inner surface C; provided annular antenna 3
C;Il! to heat the plasma 4 through 0;・In the figure, 32 is a waveguide, and this waveguide 32 is configured to guide the high frequency current from the high frequency heating device to the antenna 30C. Figure 4≦
2. An annular center electrode 34 as shown. Faraday Shield 36. 'J8 and a reflux conductor 3B. The center electrode 34 is for RF heating the plasma 4 by passing a high frequency current from the waveguide 32, and is made of a metal plate with good conductivity formed into an annular shape. . And Faraday Shield 3
6 are arranged in two sections so as to surround the surface of the center electrode 34 facing the plasma 4, and are fixed to the circulation conductor 38.
The Faraday shield 36 has an eco-constructed structure in which a highly conductive metal plate is bent into a channel shape and arranged in parallel in a direction perpendicular to the longitudinal direction of the center electrode 34 to form an arc; a slit between the metal plates. Similar metal plates are arranged in double sections to shield the slit portion.

Such a Faraday shield 36 is connected to the center electrode 34.
This is to prevent the high-frequency current from passing through the slit and entering the plasma 4, and the high-energy plasma particles emitted from the plasma 20 from colliding with the center electrode 34C, thereby preventing the center electrode 34 from overheating. and.

The return conductor 38 is provided around the outer periphery of the center electrode 34 and is configured to fix the Faraday shield 36 and allow the high frequency current of the center electrode 34 to flow back to the waveguide 32.

[Problems with evening view technology]

In the conventional device, the Faraday shield 36 is collided with high-energy plasma particles and is heated to a high temperature by the super-temperature plasma 4, so that the Faraday shield 36 is heated and the C melts.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a plasma heating antenna capable of cooling the Faraday shield and preventing overheating of the Faraday shield. A central conductor that surrounds the cross section of the plasma and flows a high-frequency current, and a direction C that surrounds the 121112-faced curve of the central conductor and intersects with the longitudinal direction of the central conductor; a plurality of tubular shapes arranged in parallel; With a Faraday shield formed by the body.

The outer periphery of the center conductor is provided with a Faraday shield for circulating high frequency current from the center conductor, and a Faraday shield having a flow path for supplying and discharging a cooling medium. .

Therefore, the S2 cooling medium inside the Faraday shield formed by the tubular body? Cool the Faraday shield in the sink, add it, @? [Embodiment of the Invention] A first embodiment of the present invention will be described with reference to FIGS. 5 and 6. In the figure, is the same symbol as the previous one?
This will be explained below.

FIG. 5 is a partially cutaway T perspective view of the first embodiment, and numeral 34 in the figure is a center electrode.

The surface of the center electrode 34 facing the plasma 4 is surrounded by a Faraday shield 40. This Faraday shield 40 has tubular bodies 42 arranged in parallel in the longitudinal direction ζ of the center electrode 34; It is fixed to a reflux conductor 44 provided on the outer periphery of the pipe.

Fins 46 are protruded from the outer circumferential surface of the tubular body 42 (-). The fins 46, as shown in FIG. 6, shield the gap between adjacent tubular bodies 42.

Moreover, the fins 46 are formed so as to overlap each other so as not to contact each other.

A flow path 50 through which a cooling medium flows to cool the Faraday shield 40 is formed in the reflux conductor 44. It is configured to supply a cooling medium, pass through the tubular body 42, cool the tubular body 42, and discharge the cooling medium from the left channel 5o.

The configuration as described above has the following effects. That is, the Faraday shield 40, which is heated by colliding with high-energy plasma particles or heated by ultra-high temperature plasma, is formed of a tubular body 42, and a cooling medium is flowed inside the tubular body 42. Therefore, the tubular body 42
The Faraday shield 40 can be cooled down, thus preventing the Faraday shield 40 from overheating and increasing its reliability and performance.

Furthermore, since the Faraday shield 40 is formed of the tubular body 42, it has the same rigidity and mechanical strength as compared to a flat plate.Furthermore, the tubular body 42 has fins 46 protruding from it. Therefore, the collision of plasma particles with the center electrode 34 is ensured f.
The second embodiment of the present invention will be described with reference to Figures 7 to 11. In the second embodiment, the seventh factor to the ninth factor≦; As shown, the fins 467 are not provided on the C two tubular body 42,
0, which is a 21@-2 array of tubular bodies 42, and
The center-to-center distance t of each tubular body 42 is 3, which is the outer radius of the tubular body 42.

If the tubular bodies 42 are arranged in two layers, the following will be ensured: Plasma particles In the case of L=28, the outer peripheral surfaces of the C tubular bodies 42 are in contact with each other, and the plasma particles 52 pass through the Faraday shield 40. There's nothing to do. next.

In the case of t=4-a, as shown in FIG. 11, the number of incident plasma particles is small (they contact the tubular body 421 three times, so the kinetic energy of the plasma particles 52 is attenuated or the traveling direction is changed). The plasma particles 52 can be deflected to prevent them from colliding with the center electrode 34 .

〔Effect of the invention〕

As explained above, according to the present invention C2, the Faraday shield heated by the plasma particle collision S and the ultra-high temperature plasma i2 can be cooled to prevent the Faraday shield from being heated.

Therefore, the effects are great, such as being able to provide a highly reliable antenna for plasma heating.

[Brief explanation of drawings]

Figure 1/ is a schematic perspective view of the fusion device, Figures 2 to 4 are diagrams showing conventional plasma heating antennas, Figure 2 is a perspective view of the antenna, and Figure 3 is the external appearance of the antenna. The fourth figure is a partially cutaway perspective view of the antenna. 5 and 6 are diagrams showing the first embodiment of the present invention, and the fifth factor is a partially broken perspective view. FIG. 6 is a cross-sectional view of the Faraday shield 4o. jl! Figures 7 through 11Q are diagrams illustrating the second embodiment of the present invention, number 73 is a partially cutaway perspective view of the antenna, and figure 8 is a vertical sectional view of the antenna. The ninth factor is within the cross section of Faraday shield 4o. Figures 1O to 11)! It is an explanatory diagram showing the relationship between the outer diameter radius and the center distance t of the tubular body 42 □ 2... Vacuum vessel, 4... Plasma, 30... Antenna, 32...
- Waveguide, 34... Center electrode, 36° 40... Faraday shield, 3B... Reflux conductor. 42... Tubular body, 50... Channel, 44... Reflux conductor. Applicant's Representative Patent Attorney Suzu Hiko

Claims (2)

[Claims] (1) A central conductor having an annular shape surrounding a cross-section of a torus-shaped plasma and through which a high-frequency current flows; and a central conductor surrounding a surface of the central conductor facing the plasma and arranged in parallel in a direction intersecting the longitudinal direction of the central conductor. A Faraday shield formed of a plurality of tubular bodies, and a circulation path provided on the outer periphery of the center conductor for circulating high frequency current from the center conductor, fixing the Faraday shield, and supplying and discharging a cooling medium to the Faraday shield. A plasma heating antenna characterized by comprising a conductor. (2) The tubular body forming the Faraday shield has fins protruding from its outer peripheral surface, and the fins are formed to cover gaps between adjacent tubular bodies. A plasma heating antenna according to claim 1.