Plasma Physics Seminar

Date
Wed, Mar 29, 2017 4:00 pm - 5:00 pm
Location
ERF 1207, Large Conference Room

Description

Speaker Name: Eric Shi

Speaker Institution : Princeton University

Title : Gyrokinetic continuum simulations of turbulence in open-field-line plasmas

Abstract : The scrape off layer (SOL) of a tokamak is an edge region in which plasma flows freely along open magnetic field lines towards a material surface, where plasma losses are mediated by a Debye sheath. It is important to develop numerical codes to study the SOL because an accurate prediction for the SOL heat-flux-channel width in ITER is necessary to address major concerns regarding damage to plasma-facing components by the exhaust power. While the use of sophisticated gyrokinetic particle-in-cell and continuum codes for studies in the tokamak core region has become widespread, major code extensions or new codes are required to handle the additional challenges of the edge region. In this talk, I will present results from my thesis work on developing a gyrokinetic continuum code for the simulation of plasma turbulence in a model SOL. I will discuss details about our numerical approach, which is based on discontinuous Galerkin methods, and gyrokinetic sheath model boundary conditions. I will show results from our simulations of turbulence in the Large Plasma Device at UCLA, including the suppression of turbulence by applied flow shear, and results from our recent work in modeling a NSTX-like SOL to investigate turbulent heat-flux spreading.