Stress Tests of Transport Models Using FACETS Code

The confinement of H‐mode plasmas strongly depends on the H‐mode pedestal structure. The pedestal provides the boundary conditions for the hot core tokamak region and determines the stability properties of the plasma edge. The structure of H‐mode pedestal depends on many factors such as heating of the plasma core, neutral fueling, recycling and density and thermal transport. It is important to elucidate the primary mechanisms that are responsible for the pedestal structure in order to optimize the tokamak performance, and avoid disruptions and large scale instabilities such as neoclassical tearing mode (NTM) and edge localized modes (ELMs). In this study, the FACETS code is used to test several models for anomalous, paleoclassical and neoclassical transport in the plasma edge of tokamaks. The FACETS code is a new whole‐device integrated modeling code that advances plasma profiles in time using a selection of transport models and models for heating and particle sources. The simulation results are compared with experimental measurements from the DIII‐D tokamak.