Transporte de partículas induzido por ondas de deriva / Particle transport induced by drift waves
AUTOR(ES)
Francisco Alberto Marcus
DATA DE PUBLICAÇÃO
2007
RESUMO
We investigate the chaotic particle transport by resonant drift waves propagating in tokamaks plasma edges with ~E × ~B poloidal zonal flow, a critical problem for the understanding of the confinement properties of fusion plasmas. We assume, for large aspect ratio tokamaks, a non integrable hamiltonian model (proposed by Horton) to describe the non linear dynamical contribution to the transport. Thus, although the total flow, formed by the equilibrium flow and two dominant resonant drift waves, is not turbulent in the eulerian point of view, the lagrangian particle trajectories are chaotic. We study the influence of the electric field radial profile on the transport barriers and convective cells created by the non linear interaction between the poloidal flow and the resonant waves. For equilibria with reverse shear flows, our results show that the particle transport can be reduced by modifying the electric field profile. Futhermore, our results are applied to propose an interpretation of recent tokamak experiments developed for studying the transport reduction when a biased electrode is inserted into the plasma edge or the Scrape-Off-Layer. As an example, we use the equilibrium and fluctuating electric field radial profiles measured in the TCABR tokamak to calculate the transport during the standard ohmic and improved confinement regimes obtained in this tokamak.
ASSUNTO(S)
plasma physics física de plasma chaos caos
Documentos Relacionados
- Transporte caótico causado por ondas de deriva
- Espalhamento de ondas eletromagnéticas por esferas e cilindros magnéticos: confinamento e transporte de ondas no limite de pequenas partículas e independência da energia armazenada com relação à forma do centro espalhador
- Refratômetro por ondas evanescentes em guias de ondas planares
- Eletrostatic waves driven by electron beam-plasma interaction in some regions of space plasmas: a treatment by particle simulation
- Ondas eletrostaticas geradas por interacao de feixe de eletrons-plasma em algumas regioes de plasma espacial: um tratamento por simulacao via particulas