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/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The lithium vapor box divertor aims to detach the divertor plasma viaevaporating and condensing lithium surfaces. By evaporating lithium near or atthe divertor plate and condensing it closer to the main chamber, a lithiumvapor density gradient can be created. This density gradient ties energy lossesto poloidal distance between the target and the detachment point. The radiationzone is then prevented from reaching the X-point as the lithium ionization ratedecreases when the detachment front moves away from the divertor target. Herewe present Scrape Off Layer Plasma Simulator (SOLPS) simulations of a lithiumvapor box divertor using an NSTX-U equilibrium and PFC geometry. The parametersfor the core boundary conditions, gas puff intensity, and heat and particletransport coefficients are chosen to match experimental values. Acceptableagreement with experimental Scrape-Off Layer (SOL) widths is found, indicatinga reasonable choice of transport coefficients. In predictive simulations,lithium is added via evaporation at the target. Predictions for peak heatfluxes and upstream impurity concentration are given for a variety ofevaporation rates. Target electron temperature is predicted to be able to bereduced to recombination levels (below 1 eV) for lithium evaporation rates of$1\cdot10^{23}$ Li/s, indicating detachment. Peak heat flux at the lower outertarget could be reduced by as much as a factor of six while maintainingupstream lithium fractions below 2%. The prevention of lithium from reachingthe midplane is shown to be due to an increase in frictional forces acting onthe lithium from a deuterium gas puff. Lithium is also shown to be redepositedclose to the evaporator which is favorable for initial tests and futurecapillary porous systems.

Predictive Modeling of a Lithium Vapor Box Divertor in NSTX-U using SOLPS-ITER