Wall conditioning in ASDEX upgrade

被引：44

作者：

Rohde, V. ^{[1
]}

Dux, R. ^{[1
]}

Kallenbach, A. ^{[1
]}

Krieger, K. ^{[1
]}

Neu, R. ^{[1
]}

机构：

[1] EURATOM, Max Planck Inst Plasmaphys, D-85748 Garching, Germany

来源：

JOURNAL OF NUCLEAR MATERIALS | 2007年 / 363卷

关键词：

ASDEX upgrade; boronisation; gas injection and fueling; wall conditioning; wall pumping;

D O I：

10.1016/j.jnucmat.2007.01.200

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

An overview on wall conditioning in ASDEX Upgrade is presented. Helium glow discharges (HeGD) are needed mostly for plasma start up after high density discharges, disruptions and disruption mitigation gas puffs. Boronisation is routinely applied. The reduction of the oxygen content is a minor effect. Strong variation of the wall pumping is observed for tungsten first wall materials. The uncoated tungsten surface stores and releases large amounts of He, which can disturb the plasma. The released He causes the modification in the wall pumping. By reducing HeGD this effect could be minimized. Advanced and natural density scenarios are sensitive to the status of the wall coating. Accumulation of impurities at the pedestal influences the ELM frequency and finally causes radiation unstable discharges. (c) 2007 Elsevier B.V. All rights reserved.

引用

页码：1369 / 1374

页数：6