SOLPS simulations of detachment in a snowflake configuration for the future upper divertor in ASDEX Upgrade. (13th June 2018)

• Record Type: Journal Article
• Authors: Pan, O; Lunt, T; Wischmeier, M; Coster, D
• Other Names: collab.
• Is Part Of: Plasma physics and controlled fusion. Volume 60:Number 8(2018:Aug.)
• Publication Date: 2018-06-13
• Subjects: SOLPS simulation -- snowflake divertor -- detachment; Plasma (Ionized gases) -- Periodicals; Controlled fusion -- Periodicals; 530.44
• DOI: 10.1088/1361-6587/aac706
• Languages: English
• ISSNs: 0741-3335

Abstract

Abstract: We report on the first SOLPS simulations of a low-field side snowflake minus (LFS SF − ) configuration in ASDEX Upgrade (AUG). This configuration will become accessible in AUG after the foreseen hardware modification of its upper divertor. Spatially constant transport coefficients, an input power of 5 MW and a nitrogen seeding rate leading to a radiative fraction of 86% were assumed. This radiative fraction is 9% higher than that for a single null reference with the same transport coefficients, similar upstream parameters and separatrix impurity concentrations. As a consequence the LFS SF − configuration achieves a larger degree of detachment and reduced heat fluxes to the targets. This heat flux mitigation was found to be significantly stronger than that expected from a simple scrape-off layer splitting model.