The goal of the GSEP SciDAC Center is to develop predictive capability for assessing the effects of energetic particles on the performance of the burning plasmas in ITER. As part of this effort, we are analyzing the fluid and particle data to identify the coherent structures in each and the non-linear interactions between them.

Our initial focus is on the structures in the ion heat flux variable in the fluid data (see Figure 1). Such analysis is difficult as the structures are complex, there is no definition of the structures, and we need a robust algorithm that can identify and extract structures that vary considerably over time. Our goal is to extract the structures and obtain statistics such as the distribution of the sizes of the structure and the variation of the sum of the ion heat flux in a structure vs. its size.

Figure 1. Left: the ion heat flux variable in one poloidal plane (grid points with similar color have similar values). Right: the structures identified, with all grid points in a structure identified by a single color.
Figure 1. Left: the ion heat flux variable in one poloidal plane (grid points with similar color have similar values). Right: the structures identified, with all grid points in a structure identified by a single color.

This work is a collaboration with Drs. Zhihong Lin and Yong Xiao at UC Irvine.

Publications

For papers and presentations related to GSEP analysis, see StarSapphire Publications.