Interaction between neoclassical and turbulent transport phenomena in negative triangularity tokamaks

Negative triangularity shaping has been shown to improve confinement in tokamaks by suppressing turbulent transport, which is the dominant mechanism of transport. Neoclassical electron transport is generally very low in comparison. However, the impact of triangularity on the multi-scale interaction between small-scale turbulent transport, driven by instabilities such as ion-temperature-gradient (ITG) and trapped-electron-modes (TEM), and larger-scale neoclassical physics has not been well-explored. We use the total-f global gyrokinetic code XGC to simulate core plasma behavior in an electrostatic model, including neoclassical and turbulence physics together and comparing the resulting heat fluxes between positive and negative triangularity plasmas.