Method for cleaning first wall of magnetic confinement fusion device by using high-frequency field

Abstract

The invention discloses a method for cleaning a first wall of a magnetic confinement fusion device by using a high-frequency field. The method is implemented by the steps of: (1) previously filling gas of 0.1-10 Pa in a vacuum chamber of the magnetic confinement fusion device; (2) arranging a high-frequency antenna in the vacuum chamber of the magnetic confinement fusion device, then taking the vacuum chamber of the magnetic confinement fusion device as a negative electrode and the high-frequency antenna which extends into the vacuum chamber of the magnetic confinement fusion device as a positive electrode, and applying the high-frequency field with voltage of 3-5 KV, frequency of 20-50 KHz and power of 2-10 KW between the negative electrode and the positive electrode; and (3) breaking down gas under the action of ionization of the high-frequency field and generating stable high-frequency plasma discharge, performing effective bombardment on the first wall of the vacuum chamber of the magnetic confinement fusion device, and cleaning the first wall after discharge cleaning of 1-10 hours. Through the method, the cleaning efficiency can be doubled.

Description

technical field [0001] The invention relates to a method for cleaning the first wall of a vacuum chamber of a magnetic confinement fusion device, in particular to a method for cleaning the first wall of a magnetic confinement fusion device by using a high-frequency field. Background technique [0002] Wall treatment technology is widely used in tokamak-type magnetic confinement fusion devices to reduce the background impurity level of the device and improve the recirculation of the device wall. Magnetic confinement fusion experiments before the 1970s did not pay enough attention to the first wall problem and the characteristics of the edge plasma. The plasma obtained at that time was not clean, mixed with various impurities, had a large number of effective charges, and the plasma density was not easy to control , resulting in lower plasma parameters. Since the 1980s, with the in-depth study of the tokamak, a series of wall treatment technologies have been developed, such as...

AI Technical Summary

Problems solved by technology

Magnetic confinement fusion experiments before the 1970s did not pay enough attention to the first wall problem and the characteristics of the edge plasma. The plasma obtained at that time was not clean, mixed with various impurities, had a large number of effective charges, and the plasma density was not easy to control , resulting in lower plasma parameters

However, in the ion cyclone cleaning, the plasma is mainly concentrated in the annular area in the center of the device, which is mainly used to clean the first wall surface facing the plasma, while the impurities in the diagnostic window and shadow area are difficult to be removed.

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