<empty>
Home Trabalhos Científicos Artigos em Revistas Científicas Plasma Physics Controlled Fusion

Plasma Physics Controlled Fusion

Influence of Electrode and Limiter Biasing on the ISTTOK Plasma

  C. Silva, H. Figueiredo, I. Nedzelsky, B. Gonçalves, J. A. C. Cabral, C. A. F. Varandas e G. Van Oost
  2004
  Ver Publicação
 
Resumo
 
In this contribution, limiter and electrode biasing experiments are compared, in particular with regard to their effects on the edge plasma parameters. For a positive electrode bias (EB), the plasma potential profile is strongly modified in the region between the electrode and the limiter. Both the edge E r and its shear increase significantly (values of E r larger than 10 kVm-1 have been measured). The modification in the edge parameters is accompanied by a substantial increase in the average plasma density and an improvement in the gross particle confinement. For moderate/high plasma densities no steady-state discharges have been achieved with EB since a degradation in confinement is observed a few milliseconds after the bias is applied. For negative bias (-250 < V bias < 0 V), no significant modification in either the global or the edge parameters is observed since the electrode current drawn is too low to modify the plasma parameters. The general discharge behaviour for positive limiter biasing is similar to that observed with EB. However, the larger increase in radiation losses and the smaller modification of the edge electric field observed when bias is applied leads to almost no modification in particle confinement and to a stronger and faster degradation in confinement a few milliseconds later.

 

Versão Portuguesa Englsih Version Páginia Inicial / Main Page

[ Artigos em Revistas Científicas ] [ Comunicações a Reuniões Científicas ] [ Teses de Mestrado ] [ Teses de Doutoramento ] [ Relatórios Internos ]

Webmaster
Copyright © 2008 Centro de Fusão Nuclear