SEMINAIRE MERCREDI 7 JUILLET 2004
14 heures
Salle Séminaire 5
Centre de Physique Théorique
Marseille-Luminy

Dmitry Volchenkov
St.-Petersburg State University

Title: Stochastic model of long-range turbulent transport in the Scrape-Off Layer of ITER

Abstract: Two dimensional stochastic model of turbulent transport in the
scrape-off layer (SOL) of ITER is considered. Instabilities are arisen
in the system with respect to the stochastic perturbations of both
either density or vorticity and reveal them self in the strong outward
bursts of particle density propagating ballistically across the SOL. A
possibility to stabilize the system depends upon the reciprocal
correlation time between density and vorticity fluctuations. Pdf of
the particle flux for the large magnitudes of flux events can be
modelled with a simple discrete time toy model of random walks
concluding at the boundary. The spectra of wandering times feature the
pdf of particle flux in the model and qualitatively reproduce the
experimental statistics of transport events.