Abstract
<!-- p, li { white-space: pre-wrap; } --><p style="text-indent: 0px; margin: 0px;">In this article we have used the 2D fluid turbulence numerical model, ESEL, to simulate turbulent transport in edge tokamak plasma. Basic plasma parameters from the ASDEX Upgrade and COMPASS tokamaks are used as input for the model, and the output is compared with experimental observations obtained by reciprocating probe measurements from the two machines. Agreements were found in radial profiles of mean plasma potential and temperature, and in a level of density fluctuations. Disagreements, however, were found in the level of plasma potential and temperature fluctuations. This implicates a need for an extension of the ESEL model from 2D to 3D to fully resolve the parallel dynamics, and the coupling from the plasma to the sheath.</p>
Highlights
IntroductionTransport (mainly turbulent) in the outermost plasma region, in contact with material surfaces, regulates particle and heat loads on plasma-facing components
Transport in the outermost plasma region, in contact with material surfaces, regulates particle and heat loads on plasma-facing components
The differences in the simulations were in radial boundary conditions (Neumann or Dirichlet) for plasma density, plasma potential, radial electric field and electron temperature, value of the the neoclassical Pfirsch-Schluter perpendicular collisional diffusion coefficient for particles D⊥n, value of parallel loss time for particles τ n or in the form of the bracket Ψ in the last term in the equation (9)
Summary
Transport (mainly turbulent) in the outermost plasma region, in contact with material surfaces, regulates particle and heat loads on plasma-facing components. In comparisons between the ESEL and the ASDEX Upgrade plasma, with higher temperature and lower collisionality than in TCV tokamak, there were great discrepancies [5]. In this case the temperature and potential were measured as well. The radial profile of the density in the ESEL was too flat, and relative temperature and electric potential fluctuations in the model were too large compared with experimental values. Temperature and electric potential fluctuations were even larger than before [5] From this time forth, a change in the extra term and extensive investigation of the parameter dependence in ESEL matching the ASDEX Upgrade plasma has been made. The purpose of this work is to show vol no. /
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
