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Information × Registration Number 0220U102141, 0118U006801 , R & D reports Title Development of perspective high-frequency methods of cleaning and preparation to the working digits of an internal vacuum surface of the thermonuclear setting with the magnetic withholding of plasma. popup.stage_title Head Moiseienko Volodymyr Ye., Кандидат фізико-математичних наук Registration Date 10-03-2020 Organization National Science Center "Kharkiv Institute of Physics and Technology" popup.description2 High frequency (HF) discharges are used to clean the inner walls of vacuum chambers of thermonuclear installations. Experimental studies of the characteristics of nitrogen plasma generated by the HF discharge in the VHF range. The experiments were performed on a stellarator (torsatron type) Hurricane-2M (U-2M). A new T-shaped antenna was installed on the U-2M, which is a monopolar quarter-wave vibrator and capable of generating slow waves. High-frequency power was up to 3 kW at an operating frequency of 130 MHz. Working gas (nitrogen) pressure 4 • 10−2 Pa, stationary magnetic field ≈ 0.01 T. Local characteristics of the plasma discharge were measured by single Langmuir probes located at different points of the torus of the installation.To determine the charge state of the ions and the elemental composition of the plasma, a non-contact passive method of optical plasma spectroscopy was used. The VHF discharge is volumetric: the plasma occupies the entire volume of the vacuum chamber. The characteristic value of the plasma density is 109 cm − 3, and the electron temperature varies within 8–10 eV. In the optical emission spectrum of the plasma observed lines N2, N2 +, as well as the radical CN.Advanced diagnostics of thermal desorption have been made, installed and used in the U-2M stellarator to measure the in situ velocity of stainless steel gas and the number of layers of molecules on its surface in four different cross sections. A detailed description of this diagnosis, the location of stainless steel thermal desorption probes and a method for determining their gas release rate and the number of molecular layers of residual gases on their surfaces in a U-2M vacuum chamber. Using this method in conjunction with mass spectrometric measurements, a study of the release of gases from the wall before and after purification of hydrogen, helium and argon plasma by HF discharges was also carried out.  Product Description popup.authors VOYTSENYA Volodymyr S GLAZUNOV Gennady P GRIGORIEVA Lyudmila I DREVALʹ Mykola B KOVTUN Yuriy V KRASYUK Oleksandr Yu KULIK Yulia S LYSTOPAD Mykhaylovych Viktor M MAZNICHENKO Sergey M MOISEENKO Vladimir E ROMANOV Vladislav S SUSKO Evgeny V TARASOV Igor K popup.nrat_date 2020-04-02 Close