Flow shear suppression of pedestal ion temperature gradient turbulence-A first principles theoretical framework

摘要

A combined analytic and computational gyrokinetic approach is developed to address the question of the scaling of an important class of pedestal turbulent transport with arbitrary levels of E x B shear. Due to strong gradients and shaping in the pedestal, the ion temperature gradient driven instabilities of interest are not curvature-driven like typical core instabilities. By extensive numerical (gyrokinetic) simulations, it is demonstrated that pedestal modes respond to shear suppression very much like the predictions of a basic analytic decorrelation theory. The quantitative agreement between the two provides us with a new, first principles (physics-based) theoretical framework for pedestal shear suppression in regimes ranging from present-day experiments to future burning plasmas that lie in low shear regimes.