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Author Poznyak, I. M. ♦ Safronov, V. M. ♦ Zybenko, V. Yu.
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword PLASMA PHYSICS AND FUSION TECHNOLOGY ♦ ACCELERATION ♦ CORIOLIS FORCE ♦ DIAGRAMS ♦ EROSION ♦ FIRST WALL ♦ HEATING LOAD ♦ ITER TOKAMAK ♦ LAYERS ♦ METALS ♦ PLASMA GUNS ♦ PRESSURE GRADIENTS ♦ PROTECTIVE COATINGS ♦ SURFACES ♦ THICKNESS
Abstract During the operation of ITER, protective coatings of the divertor and the first wall will be exposed to significant plasma heat loads which may cause a huge erosion. One of the major failure mechanisms of metallic armor is diminution of their thickness due to the melt layer displacement. New experimental data are required in order to develop and validate physical models of the melt layer movement. The paper presents the experiments where metal targets were irradiated by a plasma stream at the quasi-stationary high-current plasma accelerator QSPA-T. The obtained data allow one to determine the velocity and acceleration of the melt layer at various distances from the plasma stream axis. The force causing the radial movement of the melt layer is shown to create an acceleration whose order of magnitude is 1000g. The pressure gradient is not responsible for creating this large acceleration. To investigate the melt layer movement under a known force, the experiment with a rotating target was carried out. The influence of centrifugal and Coriolis forces led to appearance of curved elongated waves on the surface. The surface profile changed: there is no hill in the central part of the erosion crater in contrast to the stationary target. The experimental data clarify the trends in the melt motion that are required for development of theoretical models.
ISSN 10637788
Educational Use Research
Learning Resource Type Article
Publisher Date 2017-12-15
Publisher Place United States
Journal Physics of Atomic Nuclei
Volume Number 80
Issue Number 7


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