Abstract Details
Abstracts
Author: Myriam Hamed
Requested Type: Poster
Submitted: 2024-04-12 13:45:24
Co-authors: D. R. Hatch, M. J. Pueschel, J. Schmidt, C. Stephens
Contact Info:
The university of Texas
Institute for Fusion Studies,
Austin, 78712
United stated
Abstract Text:
Magnetic confinement fusion research relies on accurate prediction of turbulent transport in tokamak edge plasma to optimize device operation. This work focuses on understanding electron heat transport driven by microtearing modes (MTs).
Analysis of conventional tokamak plasmas suggests
that small-scale instabilities localized near the rational surface, such as microtearing modes, have a significant effect on confinement in tokamak. MT draws on the electron temperature gradient as a free-energy source and rearranges magnetic topology through the creation ion-Larmor-radius-scale magnetic islands and thereby playing some role in determining the pedestal characteristics.
In order to understand the causes and the evolution of the electron heat transport in tokamak discharges, a reduced kinetic transport model based on electromagnetic quasilinear theory has been implemented in the eigenvalue code Solve-AP.
This reduced model is a derivation of a current sheet model by solving the Fokker$-$ Planck and Maxwell equations and its evaluation inside the resistive layer is obtained from a system of two equations linking
the vector potential and the electric potential. This system of equations is solved numerically using an eigenvalue
code, called Solve AP. This reduced transport model is tested and compared with gyrokinetic simulations using JET
experimental data showing a good agreement. Analysis of nonlinear gyrokinetic simulations shows that a quasilinear
transport model for microtearing transport reproduces gyrokinetic trends for a variety of parameter regimes.
To achieve faster prediction of heat fluxes, a database using Solve-AP simulations has been developed. This database will be used to train a machine learning model, allowing for faster and prediction of heat electromagnetic heat fluxes in the future, particularly in the critical tokamak pedestal region.
Comments:
Plasma equilibrium, stability, and transport