JPS61245500A - Ion cyclotron heater connection system - 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 coupling system for an ion cyclotron heating device that heats plasma or drives a current in a nuclear fusion device.

[Technical background of the invention] A conventional example will be explained with reference to FIGS. 2 to 4.

Figure 2 is a vertical cross-sectional view showing the schematic configuration of the fusion device.
Reference numeral 1 in the figure indicates a vacuum container. This vacuum container 1 has a toroidal shape and maintains a high vacuum state inside to form plasma 2. A blanket 3 is installed on the inner peripheral side of the vacuum container 1 so as to surround the plasma 2. This blanket 3 accommodates lithium as a tritium breeding material therein, and is provided with a coolant flow path for cooling the lithium. The blanket 3 reacts high-energy neutrons emitted from the plasma 2 with lithium to generate tritium, and extracts the thermal energy generated at this time to the outside via the coolant flowing through the coolant flow path.

A shielding body 4 is installed on the outer peripheral side of the vacuum container 1, and the shielding body 4 prevents radiation from leaking to the outside. Further, on the outer peripheral side of this shield 4, a toroidal coil 5 is installed in the toroidal direction of the vacuum vessel 1, and a main poloidal coil 6, a sub-voloidal coil 7, and a magnetic limiter coil 8 are installed in the poloidal direction of the vacuum vessel 1. is installed. The toroidal coil 5 and both poloidal coils 6.7 form a magnetic field generating coil. Further, the magnetic limiter coil 8 is connected to the vacuum container 1.
The shape of the plasma 2 inside is restricted by magnetic lines of force. Further, each of these coils and the vacuum container 1 are placed and fixed on a pedestal 13.

A center column 11 is disposed in the center of the vacuum container 1 so as to penetrate vertically. A current transformer coil 12 is wound around the outer periphery of this central support 11.
2 and the magnetic field generating coil constitute a current transformer.

Then, a high current is passed through the magnetic field generating coil, and the vacuum vessel 1 is
Generates a magnetic field within. The plasma 2 in the vacuum container 1 is Joule heated and raised in temperature by the current generated by the generated magnetic field. Note that the reference numeral 19 in the figure indicates an exhaust pipe, which communicates with a vacuum evacuation device (not shown) through the exhaust pipe 19.
This evacuation device maintains the inside of the vacuum container 1 at a high vacuum.

An ion cyclotron heating device (hereinafter referred to as ICRF) 21 is installed around the vacuum vessel 1 . I
In general, the CRF 21 amplifies a high frequency wave transmitted from a high frequency excitation section using an amplifier section, and transfers the amplified wave to a power feeding section. The high frequency waves transferred to the power feeding section are injected into the plasma 2 by the ICRF coupling system 22 via the transmission system. Below, this ICRF coupling system 2
The second configuration will be explained. Figure 3 shows ICRF coupling system 2
2, and FIG. 4 is an enlarged view of the tip thereof. Reference numeral 31 in the figure is an antenna (center conductor), and a return conductor 32 is installed in front of this antenna 31. A high frequency current flows through the antenna 31, and the return conductor 32 serves as its return path. A Faraday shield 33 is installed on the plasma side of the antenna 31. The Faraday shield 33 short-circuits unnecessary electric field components that do not contribute to heating the plasma 2.

These antenna 31, return conductor 32, and Faraday shield 33 constitute an antenna structure. On the other hand, reference numeral 35 in the figure indicates a circumferential tube, and the inner conductor 35A of the circumferential tube 35 is connected to the center conductor 31, and the outer conductor 35B is connected to the return conductor 32. Incidentally, in FIG. 4, reference numeral 36 indicates the first wall, and reference numeral 37 indicates an alignment stub. ICRF with such a configuration
Radio frequency heating is performed via the coupling system 22 to roughly heat the plasma 2 or to drive the plasma 2 with current.

[Problems with background technology] According to the above configuration, there were the following problems.

In general, a nuclear fusion device that generates neutrons through a DT reaction has a large heat load. Therefore, in the ICRF coupling system 22, it is necessary to provide sufficient neutron shielding at the torus structure penetration part, and to effectively reduce nuclear heat generation. Needs to be removed. Conventionally, this neutron shielding has been achieved by installing a plurality of divided shielding plates (for example, made of austenitic stainless steel) and by providing cooling pipes to circulate cooling water. However, as described above, the torus structure penetration part of the ICRF coupling system 22 has a complicated configuration in which the circumferential tube 35, alignment stub 37, etc. are installed, and the neutron shielding and nuclear heat generation of the above-mentioned configuration are If the removal configuration is used, there are problems in manufacturing and installation, and it cannot be said that leakage of neutrons (hereinafter referred to as streaming) can be reliably prevented.

[Object of the Invention] The present invention has been made based on the above points, and its purpose is to provide a method that is easy to manufacture, can reliably shield neutrons, and can effectively eliminate nuclear heat generation. An object of the present invention is to provide an ion cyclotron heating device coupling system that can be used.

[Summary of the Invention In other words, the ion cyclotron heating device coupling system according to the present invention is an ion cyclotron heating device coupling system in which a circumferential tube passes through the torus structure of a fusion device to face the plasma, and an antenna is installed at the tip of the circumferential tube. The system is characterized in that the torus structure penetrating portion is filled with metal pebbles and that cooling water is circulated.

That is, the torus structure penetrating portion is filled with metal pebbles and cooling water is circulated.The metal pebbles and the cooling water perform a neutron shielding function, and the cooling water removes nuclear heat generation.

[Embodiment of the Invention] An embodiment of the invention will be described below with reference to FIG. Note that parts that are the same as those in the prior art are denoted by the same reference numerals, and their explanations will be omitted. FIG. 1 is a perspective view showing the torus structure penetration portion of the ICRF coupling system 122. This ICRF coupling system 1
22 is covered by a jacket 123, and is handled together with this jacket 123 from the penetration part during disassembly or repair, for example.

Note that the figure shows a state in which the jacket 123 is removed. Further, reference numeral 124 in the figure indicates a bottom plate.

The jacket 123, return conductor 32 and bottom plate 1
In the space surrounded by 24 (in which the circumferential pipe 35 is disposed), a partition plate 131 having a cross-shaped cross section is provided.
is installed. This partition plate 131 divides the space into four chambers 132 . These four chambers 132
Inside is Pebble 133 made of austenitic stainless steel.
is filled. This pebble 133 shields neutrons. Although some parts are omitted in the figure, the pebble 133 is filled in the entire area of the penetrating portion.

Cooling water also flows within the chamber 132. That is, an opening (not shown) is formed at the tip of the partition plate 131, and cooling water supplied from the direction indicated by arrow A in the figure flows into the upper chamber 132 through the opening. By circulating the cooling water in this manner in the direction indicated by the middle arrow B, nuclear heat generation is effectively removed and neutrons are shielded. Although not shown in the drawing, similar cooling water is distributed in the two chambers 132 on the opposite side. That is, instead of installing a plurality of shielding plates and arranging cooling pipes to flow cooling water as in the past, a partition plate 131 having a cross-shaped cross section is installed and pebbles 133 are filled therein. At the same time, by adopting a configuration in which cooling water is circulated, we aim to improve manufacturability and improve the neutron shielding function and the nuclear heat removal function.

According to this embodiment, the following effects can be achieved. That is, installing the partition plate 131 having a cross-shaped cross section is easier than installing a plurality of conventional shielding plates, and filling the partition plate 133 with the pebbles 133 is easier than installing the partition plate 131 having a cross-shaped cross section. This is an easy task even though the penetration part has a complicated structure with the alignment stub 37 and the like. Therefore, a desired shielding structure can be easily achieved, and the manufacturability is not a problem as in the past. Also, the neutron shielding function is extremely effective because the pebble 133 is filled and the cooling water is distributed over the entire area of the penetration portion. Furthermore, nuclear heat generation can be more effectively removed by the circulation of the cooling water.2 The present invention is not limited to the above embodiments, and various shapes such as the shape of the partition plate, the shape and material of the pebble, etc. The following are possible.

[Effects of the Invention] As detailed above, according to the ion cyclotron heating device combination system of the present invention, it is possible to improve the neutron shielding function and the nuclear heat removal function, and also to improve the ease of manufacturing and assembling. The effect is great.

[Brief explanation of drawings]

Figure 1 is a perspective view of a torus structure penetration part of an ion cyclotron heating device coupling system showing an embodiment of the present invention, Figures 2 to 4 are diagrams used to explain the conventional example; FIG. 3 is a longitudinal cross-sectional view showing a schematic configuration of the fusion device, FIG. 3 is a perspective view of the entrance part of the ion cyclotron heating device coupling system, and FIG. 4 is an enlarged perspective view of a part of FIG. 3. DESCRIPTION OF SYMBOLS 1... Vacuum container, 2... Plasma, 31... Antenna, 122... Ion cyclotron heating device coupling system, 131... Partition plate, 132... Pebble. Applicant's agent Patent attorney Takehiko Suzue Figure 3 Figure 4

Claims (2)

[Claims] (1) In an ion cyclotron heating device coupling system in which a circumferential tube is passed through the torus structure of a fusion device to face the plasma and an antenna is installed at the tip thereof, the torus structure penetration portion is filled with metal pebbles. With,
An ion cyclotron heating device combination system characterized by circulating cooling water. (2) The ion cyclotron according to claim 1, wherein a partition plate having a cross section is installed in the torus structure penetrating portion, and the partition plate forms an inflow/outflow channel for cooling water. Heating device coupling system.