Linear Analysis and Verification Suite for Edge Turbulence Simulations

Research in fusion energy is becoming increasing reliant on large-scale plasma simulations for both scientific understanding and hardware design. In particular, the edge physics simulation projects, currently being undertaken in the US and international communities, could benefit greatly from standardized benchmarks. One of the few quantitative ways to rigorously benchmark turbulence codes, with each other and with a universal standard, involves the measurement of the linear growth rate of unstable modes that emerge from a known, established equilibrium configuration. This project will develop such a standard, namely, an axisymmetric, toroidal geometry, linear-edge physics code suite. This suite, which will consist of a new eigenvalue code plus the recently revised BOUT code, will be a community wide benchmarking/verification tool for nonlinear edge plasma simulation codes. The suite also will have stand-alone uses for the analysis of experiments and for the theoretical study of edge plasma regimes. Phase I will demonstrate feasibility with respect to: (1) numerical implementation of the 2D eigenvalue problem in mixed magnetic topology, (2) the development of methods to incorporate kinetic physics, and (3) benchmarking tests with the BOUT code. Commercial Applications and other Benefits as described by the awardee: Limited funding available for edge-turbulence simulation projects in the US has resulted in even more limited resources being available for verification and benchmarking. The linear code suite should fill a unique niche in the fusion energy program.