Is turbulence indeed reduced in the tokamak edge pedestal?

Silvia Espinosa


Wednesday, October 14, 2015



PSFC Student Seminars


It has been suggested that the sudden transition between states of low and high confinement involves the reduction of turbulence by sheared radial electric fields. For H-mode pedestals, the amount of turbulence may be only large enough to affect high order phenomena, such as heat transport. Neoclassical collisional theory may then be expected to properly treat low order phenomena, such as flows. However, H-mode edge pedestals on Alcator C-Mod exhibit significantly stronger poloidal asymmetry than predicted by the most comprehensive neoclassical models developed to date, for potential, boron temperature and density.

We propose a novel self-consistent neoclassical theoretical model that allows us to successfully capture these poloidal asymmetries, providing a more realistic predictive model for pedestal observations without the need of invoking anomalous transport. 


Silvia Espinosa graduated in 2012 with a double degree: 'BSc+MSEE in Nuclear and Alternative Energy' from the Polytechnic University of Madrid (Spain) and a 'MSc in Computational Fluid Dynamics' from Cranfield University (UK). Just before coming to MIT, she developed and parallelised (clusters and GPUs) fusion codes at CIEMAT and Max Planck IPP Garching. Her main interest is turbulence and transport theory. In her free time, she enjoys trekking, swimming, biking, traveling and getting to know other cultures. She is especially passionate about challenging adventures.