Conceptual design of a dust monitor diagnostic for ITER

Abstract

ITER requires diagnostics for monitoring of in-vessel dust and concomitant T accumulation level. To monitor these under the divertor, a dedicated diagnostic referred to as dust monitor is being developed. It will be based on a combined endoscope / dust collector designed to travel approximately 20 m. The diagnostic can use two tools-one for fine viewing of dust with resolution down to a few tens of microns across a few mm and another one for dust collection. Both endoscopes will have coarse viewing with resolution of few hundred microns over a wider area to allow the possibility for more general inspection of surrounding environment, obstacle avoidance etc. All viewing will be done using radiation hard fibre bundles. The collected dust will be characterized to determine its T-content, elemental composition, mass and size distribution.