English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Open

Presents the pdf analysis as premium feature

PDF Analysis

Insights

Presents the summarisation as premium feature

Summarisation

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

International audienceIt is shown that Ion Temperature Gradient turbulence close to the ă threshold exhibits a long time behaviour, with smaller heat fluxes at ă later times. This reduction is connected with the slow growth of long ă wave length zonal flows, and consequently, the numerical dissipation on ă these flows must be sufficiently small. Close to the nonlinear threshold ă for turbulence generation, a relatively small dissipation can maintain a ă turbulent state with a sizeable heat flux, through the damping of the ă zonal flow. Lowering the dissipation causes the turbulence, for ă temperature gradients close to the threshold, to be subdued. The heat ă flux then does not go smoothly to zero when the threshold is approached ă from above. Rather, a finite minimum heat flux is obtained below which ă no fully developed turbulent state exists. The threshold value of the ă temperature gradient length at which this finite heat flux is obtained ă is up to 30% larger compared with the threshold value obtained by ă extrapolating the heat flux to zero, and the cyclone base case is found ă to be nonlinearly stable. Transport is subdued when a fully developed ă staircase structure in the E x B shearing rate forms. Just above the ă threshold, an incomplete staircase develops, and transport is mediated ă by avalanche structures which propagate through the marginally stable ă regions. Published by AIP Publishing

Gradient-driven flux-tube simulations of ion temperature gradient turbulence close to the non-linear threshold