A test of nitrogen-assisted plasma discharges for fuel removal from plasma-facing components in tokamaks

• Safety regulations limit the amount of tritium accumulated in wall components of a fusion reactor to 350g. Because of this, reduction of long-term fuel inventory is one of the most urgent tasks to be resolved to ensure the safe and economic operation of a reactor-class fusion device. Several methods have been suggested and tested. The aim of this paper is to evaluate the cleaning efficiency of plasma-facing components by ICRH-assisted plasma discharges with in nitrogen-hydrogen in the TEXTOR tokamak. Three types of probes were investigated: laboratory prepared a-C: D layers on silicon; boron layers on silicon obtained by pre-boronisation in TEXTOR and not coated Inconel substrates. The main results are following: (i) laboratory prepared a-C: D layers are not affected: deuterium and carbon contents did not decrease (ii) the morphology of layers pre-boronised in TEXTOR is not affected (iii) no significant effects were noticed on Inconel probes. A comparison of cleaning methods with nitrogen and oxygen is also presented.

Ämnesord

NATURVETENSKAP  -- Fysik -- Fusion, plasma och rymdfysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Fusion, Plasma and Space Physics (hsv//eng)

Nyckelord

CO-DEPOSITED LAYERS

LABORATORY PLASMAS

JET

LASER

DIVERTOR

EROSION

TILES

Plasma physics

Plasmafysik

Publikations- och innehållstyp

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