Turbulence suppression by energetic particles: a sensitivity-driven dimension-adaptive sparse grid framework for discharge optimization

Abstract

A newly developed sensitivity-driven approach is employed to study the role of energetic particles in suppressing turbulence-inducing micro-instabilities for a set of realistic JET-like cases with NBI deuterium and ICRH 3He fast ions. First, the efficiency of the sensitivity-driven approach is showcased for scans in a 21-dimensional parameter space, for which only 250 simulations are necessary. The same scan performed with traditional Cartesian grids with only two points in each of the 21 dimensions would require 221 = 2, 097, 152 simulations. Then, a 14-dimensional parameter subspace is considered, using the sensitivity-driven approach to find an approximation of the parameter-to-growth rate map averaged over nine bi-normal wave-numbers, indicating pathways towards turbulence suppression. The respective turbulent fluxes, obtained via nonlinear simulations for the optimized set of parameters, are reduced by more than two order of magnitude compared to the reference results.

Document Details

Document Type
Pub Defense Publication
Publication Date
Apr 13, 2021
Source ID
10.1088/1741-4326/abecc8

Entities

People

  • A. Di Siena
  • Frank Jenko
  • Ionuţ-Gabriel Farcaş

Organizations

  • Air Force Office of Scientific Research
  • Office of Science

Tags

Fields of Study

  • Physics

Readers

  • Graph Algorithms and Convex Optimization.
  • Molecular Photonics/Laser Physics
  • Phased Array Antenna Design.

Technology Areas

  • Space
  • Space - Hall-Effect Thruster