%0 Journal Article
%A Kirschner, A.
%A Kreter, A.
%A Wienhold, P.
%A Weckmann, A.
%A Pospieszczyk, A.
%A Ding, R.
%A Borodin, D.
%A Brezinsek, S.
%A Sergienko, G.
%A Rubel, M.
%A Linsmeier, Ch.
%T Modelling of deposition and erosion of injected WF 6 and MoF 6 in TEXTOR
%J Nuclear materials and energy
%V 12
%@ 2352-1791
%C Amsterdam [u.a.]
%I Elsevier
%M FZJ-2018-00067
%P 564 - 568
%D 2017
%X Tracer injection experiments in TEXTOR with MoF6 and WF6 lead to local deposition of about 6% for Mo and about 1% for W relative to the injected amount of Mo and W atoms. Modelling of these experiments has been done with ERO applying updated data for physical sputtering. The dissociation of the injected molecules has been treated in a simplified manner due to the lack of dissociation rate coefficients. However, with this it was possible to reproduce the observed radial penetration of Mo and W atoms into the plasma. The modelled local deposition efficiencies are about 50% for Mo and 60% for W assuming typical plasma parameters for the experimental conditions used. To reproduce the measured deposition efficiencies an enhancement factor for the erosion of deposited Mo and W has to be assumed (∼10 for Mo and ∼25 for W). Due to the rather low electron temperature Te of these plasma conditions (Te∼15 eV at the location of injection), Mo and W are mostly sputtered by impurities whereas sputtering due to deuterium is negligible. A parameter study applying larger electron temperature leads to increased sputtering and thus to reduced local deposition efficiencies of about 30% for Mo and 5% for W. Though, even under these conditions enhanced erosion, albeit with reduced enhancement factors, is needed in the modelling to obtain the small measured deposition efficiencies.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000417293300089
%R 10.1016/j.nme.2016.10.022
%U https://juser.fz-juelich.de/record/841763