JPH0334299A - High-frequency heating device - 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 [Object of the Invention] (Industrial Application Field) The present invention relates to a high-frequency heating device for plasma heating in a nuclear fusion (experimental) device, etc., and particularly relates to a low-frequency hybrid wave band high-frequency heating device.

(Prior Art) Plasma heating in a nuclear fusion (experimental) device is performed by a neutral particle heating method, high frequency heating, etc. as a second stage heating method, in addition to Joule heating, which heats the plasma by passing an electric current through it. The high-frequency heating method is a method of increasing the temperature of the plasma by absorbing the energy of high-frequency electromagnetic waves into the plasma, and there are various methods depending on the frequency used, one of which is low-frequency hybrid wave band high-frequency heating. That-
An example is shown in FIG.

That is, a high-frequency oscillator that oscillates and amplifies high-power electromagnetic waves 1. A high frequency transmission system 3 that transmits the electromagnetic waves generated by this high frequency oscillator 1 to the nuclear fusion (real@) device 2. and a high frequency coupling system 5 connected to the transmission system 3 and radiating electromagnetic waves to the plasma 4.

Note that 6 is a vacuum sealing plate.

Among them, the high frequency coupling system 5 is inserted into the port 2a of the nuclear fusion (experiment) device 2, so it must be installed in a narrow space due to size constraints.

FIG. 3 shows an example of a conventional high-frequency coupling system 5 (Japanese Patent Publication No. 59-43002), in which 7 is a rectangular waveguide.
Usually, a plurality of waveguides 7 are arranged in a grid pattern.

A waveguide bundle 8 is formed.

Electromagnetic waves are transmitted through each waveguide 7 and radiated to the plasma 4 from the tip on the plasma 4 side. These waveguides 7 are entirely covered by a waveguide bundle container 9. The waveguide bundle container 9 is provided with fluid passages 9a and 9b, and the waveguide 7 and the waveguide bundle container 9 can be cooled and heated by flowing fluid such as gas through the passages 9a and 9b. . That is, before Mk4, high-temperature fluid is flown and heated in order to reduce the gas released from the waveguide 7, while during operation, low-temperature fluid is flown and cooled in order to remove Joule heat generation and irradiation heat from the plasma 4. be done.

(Problem to be Solved by the Invention) In order to increase the heating efficiency of the plasma, it is better to reduce the pitch between the waveguides 7 and use a large number of waveguides to efficiently transmit electromagnetic waves into the plasma 4. It can be input. Further, the larger the aperture ratio of the electromagnetic wave emitting section at the plasma side tip, the more efficiently the electromagnetic wave can be emitted, so it is desirable that the plate thickness of the waveguides 11 to 7 be made thinner. However, in the method of covering the waveguide 7 with a waveguide bundle container 9 and flowing fluid into the space as shown in FIG. 3, the inside of the waveguide 7 is vacuum and the outside is under fluid pressure, at least 1
Because of the external pressure of kg/J or more, it was not possible to reduce the plate thickness very much. Note that if there is no cooling/heating means, it is under vacuum and the only heat transfer is heat conduction and radiation, resulting in insufficient cooling and making it impossible to create a high-frequency heating device that can withstand high-output, long-pulse operation. Become.

The present invention has been made based on the above-mentioned circumstances, and its purpose is to make a waveguide bundle for the low hybrid wave band compact, and to enable efficient cooling and heating to achieve high output and high output.
An object of the present invention is to provide a high frequency heating device capable of plasma heating with high efficiency.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, the present invention uses a waveguide module in which a large number of waveguides are formed with thin plate partitions, and the outer periphery thereof is made within the thickness. In addition, a plurality of waveguide modules are covered with a waveguide bundle container to form a fluid flow path.

(Function) Not only can the fluid flow around the outer periphery of the waveguide module to heat and cool it, but because no external pressure acts on the partition plate, the thickness of the partition plate can be made thinner, and the pitch between the waveguides can be narrowed. This makes it possible to increase the porosity between the radiant parts and significantly improve heating efficiency.

(Embodiment) An embodiment of the high frequency heating device according to the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 3 is a sectional view of the waveguide bundle 8, and 10 is a waveguide module in which a large number of waveguides 7 are integrally formed.

A plurality of waveguide modules 10 are arranged in a grid pattern and contained in a waveguide bundle container 9. Waveguide module IO
Fluid flow paths 9a are formed on the upper and lower surfaces of the housing to enable heating and cooling.

The waveguide module 10 has a thin partition plate 11 with a thick outer circumference.
It is divided into a large number of waveguides 7. The outer periphery 10a of the waveguide module 10 forms a boundary between fluid and vacuum, and is therefore designed to be thick enough to withstand fluid pressure. Note that each waveguide module IO and the waveguide bundle container 9 are vacuum-tightly welded on both the plasma side and the anti-plasma side.

Next, the operation of this embodiment configured as described above will be explained.

Since a high frequency current flows through the waveguide 7, heat generation occurs due to Joule loss. In addition, the tip of the plasma side has plasma 4
The irradiated heat from the This heat generation is removed by the fluid flowing through the fluid flow path 9a formed by the waveguide module 10 and the waveguide bundle container 9. That is, the cooling fluid supplied via the supply pipe from an external heating and cooling system (not shown) flows through the flow path 9a to cool the waveguide module 10,
It passes through the return flow path 9b and returns to the heating and cooling system via the discharge pipe. Furthermore, during operation, although the cooling fluid flows through the waveguide module 10 as described above, the waveguide module 10 can also be heated by flowing a high-temperature fluid through the waveguide module 10. By performing this heating before operation, it is possible to reduce the amount of gas released from the waveguide module 10 and the waveguide bundle container 9, thereby reducing the inflow of impurities into the plasma 4. Furthermore, since discharge within the waveguide 7 can be prevented, high-output power can be stably transmitted.

Further, a pressure difference between fluid pressure and vacuum acts on the outer periphery 10a of the waveguide module IO, but the partition plate 11 forming the waveguide 7
Since no external pressure acts on the tube, the plate thickness can be reduced and the pitch between the single-wave tubes 7 can be narrowed, increasing the porosity between the radiating parts and significantly improving the heating efficiency.

〔Effect of the invention〕

As detailed above, according to the present invention, since the waveguide can be cooled and heated efficiently, the heat removal capacity is large, the amount of released gas can be reduced, and high-output power transmission is of course possible. ,
Since no external pressure acts on the waveguide partition plate, the plate thickness can be made thinner, making it possible to configure the waveguide module compactly.

Therefore, the aperture ratio of the radiation section on the plasma side increases, and the radiation efficiency to the plasma improves. Therefore, according to the present invention, it is possible to provide a high frequency heating device capable of plasma heating with high output and high efficiency.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing the main parts of a high-frequency coupling system of an embodiment of the high-frequency heating device of the present invention, FIG. 2 is an explanatory diagram showing the configuration of the high-frequency heating device, and FIG. 3 is a diagram showing a conventional high-frequency coupling system. FIG. ■... High frequency oscillator 2... Nuclear fusion (experimental) device 3
... High frequency transmission system 4 ... Plasma 5 ... High frequency coupling system 6 ... Vacuum sealing plate 7 ... Waveguide
8... Waveguide bundle 9... Waveguide bundle container 10
... Waveguide module 11 ... Partition plate

Claims (2)

[Claims] (1) A plurality of waveguide modules each having a large number of waveguides formed inside with a thin partition plate are assembled, and the outside of the waveguide module is covered with a waveguide bundle container, and the waveguide modules are connected between each other and the waveguide A high-frequency heating device characterized in that a fluid flow path for cooling or heating is formed between a module and a waveguide bundle container. (2) The high-frequency heating device according to claim (1), wherein the outer peripheral plate of the waveguide module is made thicker than the partition plate.