Enhanced -->E*-->B drift effects in the TCV snowflake divertor
Author | |
Abstract |
Measurements of various plasma parameters at the divertor targets of snowflake (SF) and conventional single-null configurations indicate an enhanced effect of the -->E*-->B drift in the scrape-off layer of plasmas in the SF configuration. Plasma boundary transport simulations using the EMC3-Eirene code show that the poloidal gradients of the kinetic profiles in the vicinity of the null-point of a SF divertor are substantially larger than those of a conventional single-null configuration. These gradients are expected to drive larger -->E*-->B flows in the SF divertor and are thought to be responsible for the formation of the double-peaked particle and heat flux target profiles observed experimentally. Experiments in forward and reversed toroidal magnetic field directions further support this conclusion. The formation of such a double-peaked profiles is enhanced at higher plasma densities and may have beneficial effects on the divertor heat loads since they lead to broader target profiles and lower peak heat fluxes. |
Year of Publication |
2015
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Journal |
Nuclear Fusion
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Volume |
55
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Issue |
12
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Number of Pages |
123023
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URL |
http://pubman.mpdl.mpg.de/pubman/item/escidoc:2228391:2/component/escidoc:2391697/Canal_Enhanced.pdf
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DOI |
10.1088/0029-5515/55/12/123023
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PId |
4218b275031b009ff3322c11d6691852
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Alternate Journal |
Nucl. Fusion
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Label |
OA
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Journal Article
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