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Information × Registration Number 0223U005759, 0123U103086 , R & D reports Title Research of discharges of different frequency ranges for cleaning vacuum chambers of thermonuclear installations popup.stage_title Head Siusko Yevhen V., Доктор філософських наук Registration Date 30-12-2023 Organization National Science Center "Kharkiv Institute of Physics and Technology" popup.description2 Wall cleaning is used to reduce the content of light and heavy impurities in the environment for creating plasma. This is necessary to obtain a higher plasma temperature. We took part in the experimental program OP 2.1 (2022-2023) at the Wendelstein 7-X stellarator, within the framework of which a number of electron-cyclotron resonance discharges were performed. In order to effectively observe the characteristics of the plasma during wall cleaning discharges and obtain preliminary approximations, the data obtained with the help of W7-X diagnostic tools were used: linear dispersion interferometer, high-efficiency survey X-ray spectrometer (HEXOS), pressure and reduced power data of ECRN. Unfortunately, other diagnostics were disabled or were not available to diagnose this type of pulses. The following conclusions can be drawn from the obtained experimental dependences: ECRN pulses with a power of 0.73 MW and a duration of 7 ms create a plasma with a maximum density of more than 0.235·1018 m-3. A different time interval between pulses does not change the plasma parameters. Only gives more time for pumping; it is possible to notice an increase in the maximum density with an increase in pressure; a series of lines HI (94.9740 nm, 97.2540 nm, 102.572 nm, 121.5670 nm), CII (90.4080 nm) and CIII (117.6370 nm) were recognized. Further experiments are needed to understand the cleaning capabilities of these pulses. Data from experiments conducted at the U2-M stellarator were processed. An experiment was carried out to investigate HF cleaning in a gas mixture of Ar+N2 in the proportion of 86%+14% in a small magnetic field B0= 0.01 T. Desorption of oxygen, hydrogen and carbon from the walls of the vacuum chamber was revealed from the constructed experimental dependencies. It was also found that the emission lines of impurities increase with the pressure of the gas mixture. Based on the results of the experiment, it can be firmly said that the cleaning mixture (Ar+N2) had a quit Product Description popup.authors KOZULYA Mykhaylo М. Marchuk Yriy M. Siusko Yevhen V. popup.nrat_date 2023-12-30 Close