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DOE OSTI · 1241977

The snowflake divertor

Ryutov, D. D.·Soukhanovskii, V. A.
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Abstract

The snowflake magnetic configuration is characterized by the presence of two closely spaced poloidal field nulls that create a characteristic hexagonal (reminiscent of a snowflake) separatrix structure. The magnetic field properties and the plasma behaviour in the snowflake are determined by the simultaneous action of both nulls, this generating a lot of interesting physics, as well as providing a chance for improving divertor performance. One of the most interesting effects of the snowflake geometry is the heat flux sharing between multiple divertor channels. The authors summarise experimental results obtained with the snowflake configuration on several tokamaks. Wherever possible, relation to the existing theoretical models is described. Divertor concepts utilizing the properties of a snowflake configuration are briefly discussed.

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70 PLASMA PHYSICS AND FUSION TECHNOLOGY

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Ryutov, D. D., Soukhanovskii, V. A.. 2015-11-17. The snowflake divertor. https://doi.org/10.1063/1.4935115

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