Modelling 2D Plasma Drift-Wave Turbulence in Tokamaks Using the Dedalus Python Framework

Plasmas in fusion devices such as tokamaks undergo a chaotic process called turbulence which affects their performance by controlling the rate at which particles leak out of the magnetic trap. Understanding the dynamics of turbulent transport in tokamaks and its features such as zonal flows, is an extensive field of study. We have developed a code for pseudo-spectral simulations of 2D drift wave turbulence of tokamak plasma based on the Dedalus framework (dedalus-project.readthedocs.io), an open source MPI parallelized python code. We will first present the results of the simulations for a hydrodynamic vortex merger test case in the vorticity formulation of the 2D Navier Stokes Equations with viscosity. Next, we will show the results for the evolution of the Hasegawa-Mima equations and the Terry-Horton equations, along with their properties such as enstrophy and energy conservation in the zero-viscosity case. Self-generated zonal flows can strongly reduce turbulence. We will study the impact of various models of zonal flows on the nonlinear saturation level of turbulence, including a model of the strong neoclassical shielding of zonal flows in tokamaks. This code will be made publicly available.