Powerful quasi-steady-state plasma accelerator for fusion experiments

Tungsten melt layer erosion due to J×B force under conditions relevant to ITER ELMs

“…Plasma exposures were performed with repetitive pulses of the quasi-steady-state plasma accelerator QSPA Kh-50, described elsewhere [8]. The exposed targets had a surface of 50 · 10 mm 2 and a thickness of 50 mm.…”

Simulation of iter transient heat loads to the divertor surfaces with using the powerful quasi-steady-state plasma accelerator

“…The currents in each coil were specially selected to provide spatially increasing magnetic field. Its maximum value B 0 = 0.54 T achieved in diagnostic chamber at Z S = 2.4 m from accelerator (between 3 and 4 coils) where the target has been installed [4]. The main plasma stream parameters simulating the conditions of disruption regime at the divertor plates of ITER were as follows: plasma stream energy density -(25÷30) MJ/m 2 , plasma load duration -0.25 ms, maximum plasma pressure -(16÷18) Bar, average plasma density -10 16 cm −3 , averaged value of proton energy -(150÷500) eV, plasma stream diameter -12 cm, number of pulses -up to 40.…”

“…Experiments with tungsten, graphite, combined tungsten-graphite and other targets were carried out in the quasi-steady-state plasma accelerator QSPA Kh-50 [3,4]. Pure sintered tungsten samples had a size of 5 × 5 × 1 cm.…”

“…The full-block powerful quasi-steady-state plasma accelerator, described in [3,4], consists of two stages. The first one is used for plasma production and pre-acceleration.…”

“…Quasi-steady-state plasma accelerators (QSPA), which are characterized by long duration of plasma stream generation are especially attractive facilities for investigations of plasma-surface interaction in conditions of high heat loads simulating the ITER disruptions and ELMs, as far as such accelerators provide the most appropriate modeling of the processes at the divertor plates [3,4].…”