Numerical investigation of Scrape Off Layer anomalous particle transport for MAST parameters

TL;DR

This paper uses numerical simulations to analyze turbulence and particle transport in the Scrape Off Layer of MAST, revealing how edge parameters influence plasma behavior and transport coefficients.

Contribution

It provides new insights into how edge plasma parameters affect turbulence characteristics and particle fluxes in the MAST boundary plasma through detailed numerical analysis.

Findings

Density profile broadens with decreased current or temperature.

Turbulence statistics show universality across parameters.

Transport coefficients depend nonlinearly on parameters and radius.

Abstract

Numerical simulations of L-mode plasma turbulence in the Scrape Off Layer of MAST are presented. Relevant features of the boundary plasma, such as the thickness of the density layer or the statistics of the fluctuations are related to the edge density and temperature, plasma current and parallel connection length. It is found that the density profile is weakly affected by the edge density, it broadens when the current or the temperature are decreased while the connection length has the opposite effect. The statistics of the turbulence is relatively insensitive to variations of all the edge parameters and show a certain degree of universality. Effective transport coefficients are calculated for several plasma conditions and display a strong nonlinear dependence on the parameters and on the radial variable. Finally, it is shown how the perpendicular particle fluxes in the Scrape Off Layer are related to the edge parameters.