SUMMARY
Meeting Link: https://bluejeans.com/870320372The path toward fusion as an energy source hinges on an understanding and description of the plasma dynamics. On the experimental side, great effort is being given to access and exploit high performance operational regimes such as H-Mode, SH-Mode, and NT Mode. Each of these regimes show improved plasma performance characteristics in the form of longer confinement times, but many traditional codes, such as SOLPS, UEDGE, or ONETWO satisfy fluid conservation equations in the absence of electromagnetic effects. Instead, these codes assume diffusion as the primary transport mechanism and impose electromagnetic effects after the equilibrium field has been solved. One of the key weaknesses in this modeling approach is diffusion implies that particles move down the pressure gradient, whereas the aforementioned regimes should exhibit increased transport in the presence of steep pressure gradients at the plasma edge. In fact, they exhibit exactly the opposite. The objective of this research is to produce a predictive transport model that conserves particles, momentum and energy by including the non-diffusive loss mechanism of IOL and retaining the long range electromagnetic contributions of Lorentz force (VxB). A necessary and intermediate step is to provide an iterative computational algorithm that is compatible with the strong E&M and VxB forces simultaneously with the weaker scattering forces. To this end, we will explore the Broyden algorithm, a quasi Newton-Raphson method, as the primary iterative solver in combination with Gauss reduction. A validation exercise against a variety of operational modes, L-Mode, H-Mode, NT-Mode, and Reverse Magnetic Pinch (RMP) is envisioned. The result will be a code that predicts the radial density, pressure, and temperature fields as well as the associated toroidal and poloidal velocities.