Space Plasma Seminar: Modeling the Large Plasma Device (LAPD)

Dustin Fisher, Dartmouth College

Tuesday, November 5, 2013, 3:30pm

Wilder 115

3D global two-fluid simulations are presented in an ongoing effort to identify and understand the physics of instabilities that arise in the Large Plasma Device (LAPD) at UCLA's Basic Science Facility. The LAPD, with its wide range of tunable parameters and device configurations, is ideally suited for studying space and laboratory plasmas. Moreover, the highly detailed and reproducible measurements of the LAPD lend themselves amicably to comparisons with simulations. Ongoing modeling is done using a modified version of the Global Braginskii Solver (GBS) that models the plasma from source to edge region in a fully 3D two-fluid code. The reduced Braginskii equations are solved on a field-aligned grid using a finite difference method and 4th order Runge-Kutta time stepping and are parallelized on Dartmouth's Discovery cluster. Recent progress has been made to account for the thermionic cathode emission of fast electrons at the source, the axial dependence of the plasma source, and it is now possible to vary the potential on the front and side walls in a non-trivial way. I'll discuss the 10 days I spent out in Westwood as an experimentalist helping to run the latest set of biasing tests on the LAPD and will share my latest work on the growth and structure of turbulence in the zero bias case.

For more information, contact Tressena Manning at 603-646-2854 or tressena.a.manning@dartmouth.edu.