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Pulsed plasma injectors, that is, an “input ionization chamber” (IIC), an “anode ionization chamber” (AIC), and a high-pressure plasma injector, are described. Plasma injectors are designed to generate primary plasma in quasi-stationary high-power plasmodynamic systems, in particular, in the KSPU Kh-50 quasi-stationary high-current plasma accelerator. The results of studies of the main characteristics of plasma pulsed injectors are presented. The following charge currents in plasma were obtained: 23.5 kA for the AIC injector at a voltage of 3 kV, 90 kA for the IIC injector at a voltage of 0.65 kV, and 96 kA for the high-pressure plasma injector at a voltage of 3 kV.

For the first time, the features of the interaction of plasma with materials and the erosion mechanisms have been evaluated for surfaces in a three-dimensional geometry exposed by powerful plasma. Experimental studies of the powerful interaction of plasma with the three-dimensional structures have been carried out on a quasistationary plasma accelerator QSPA Kh-50. The plasma streams with surface heat loads of 0.9 MJ/m2 and plasma pulse duration 0.25 ms, relevant to ITER ELM, have been used in the experiments. The significant erosion occurs under the action of plasma heat loads. Erosion is accompanied by the separation of material particles from the irradiated surfaces. It is found that the number and the velocity of particles emitted from the surface depend on the number of plasma pulses. The most significant factors causing a macroscopic erosion for a three-dimensional tungsten structure have been studied., Вперше дослiдженi особливостi взаємодiї плазми з матерiалами та механiзми ерозiї в тривимiрнiй геометрiї поверхнi, пiд впливом потужного плазмового опромiнення. Експериментальнi дослiдження взаємодiї потужної плазми з тривимiрними структурами виконанi на квазiстацiонарному плазмовому прискорювачi КСПП Х-50. В експериментах застосовували потоки плазми з тепловим навантаженням на поверхню – 0,9 МДж/м2 та тривалiстю плазмового iмпульсу – 0,25 мс, що є близькими до умов IТЕР ELM. Пiд впливом зазначених теплових навантажень вiдбувається суттєва ерозiя мiшенi, що супроводжується вiдокремленням часток матерiалу вiд опромiнюваних поверхонь. Встановлено, що кiлькiсть та швидкiсть часточок, якi вiдлiтають з поверхнi, залежить вiд кiлькостi iмпульсiв. Дослiдженi найбiльш значущi джерела макроскопiчної ерозiї вольфрамової тривимiрної конструкцiї.

Pulse gas valves for “anode ionization chamber” (AIC) and “input ionization chamber” (IIC) plasma injectors and features of their operation are described. The IIC and AIC plasma injectors are used for generation of primary plasma in the KSPU Kh-50 quasi-stationary strong-current accelerator. The results of studying basic gas-dynamic and electrical characteristics of the pulse gas valves are presented.

Castellated edges of macro-brush armour elements of ITER divertor can be a source of molten/solid dust particles which are injected into the plasma. The targets that combined in brush-like geometry have been irradiated under different inclination angles in QSPA Kh-50. The cubic brushes element has typical size of 1 cm. The titanium was used to investigate dynamics of mountains’ formation. The onset of dust particles ejection from the exposed castellated targets has been studied. Formation of resolidified bridges through the gaps of brush-like targets due to the melt motion is studied in dynamics. With following plasma impacts such resolidified bridges became additional source of dust.

Processes occurring in a plasma flow generated by a magnetoplasma compressor (MPC) during the formation of the compression zone are discussed. The paper presents results of measurements of the spatial distribution of the electric current in the plasma flow, the temporal and spatial (along the flow) distributions of the plasma density, and the profiles of the velocity of individual flow layers along the system axis. The spatial distribution of the electromagnetic force in the flow is analyzed. It is shown that the plasma flow is decelerated when approaching the compression zone and reaccelerated after passing it. In this case, the plasma flow velocity decreases from ν = (2–3) × 107 cm/s at the MPC output to ν < 106 cm/s in the region of maximum compression and then again increases to 107 cm/s at a distance of 15–17 cm from the MPC output. In some MPC operating modes, a displacement of the magnetic field from the compression zone and the formation of toroidal electric current vortices in the plasma flow after passing the compression zone were detected.

Results from experimental studies of extreme UV (EUV) radiation from the compression zone of a magnetoplasma compressor (MPC) operating with xenon are presented. Two MPC operating modes that differ in the method of xenon injection into the discharge were studied. It is shown that EUV radiation in the wavelength range of 5–80 nm is emitted from the compression zone. In the MPC operating mode with local xenon injection directly into the compression zone surrounded by helium plasma, the radiation power reaches it peak value of 16–18 kW in the wavelength range of 12.2–15.8 nm.

Results from experimental studies of a compact magnetoplasma compressor designed for operation with heavy gases are presented. The integral characteristics of the discharge and the energy contents and other parameters of the generated xenon plasma streams are determined.