Strong poloidal refueling asymmetry in the DIII-D tokamak is inferred from line radiation measurements. Synthetic diagnostics in neutral transport modeling coupled to gyrokinetic simulations illuminate implications for the plasma flow profile in the scrape-off layer of single-null beam-driven discharges. Recycling occurs primarily either on the inner or outer divertor legs, depending on the toroidal magnetic field direction. By reversing the toroidal magnetic field, the observed line radiation asymmetry is nearly eliminated or reversed. It is determined that, while relatively simple physics can describe the observed ionization asymmetry, predicting the overall brightness of the hydrogenic Lyman-α signal requires detailed simulation of the plasma and resulting turbulence. To this end, kinetic plasma simulations fully coupled to comprehensive neutral transport calculations—a novel capability—provide first-principles reproduction of Lyman-α observations on DIII-D.
この論文は、DIII-Dトカマクにおける強い極方向の燃料補給の非対称性を示しています。中性粒子輸送モデリングと結合したジャイロ運動論的シミュレーションにより、単一ヌル型ビーム駆動放電のスクレイプオフ層における流れプロファイルの影響が明らかにされています。トロイダル磁場の方向を逆転させることで、観測された輝線放射の非対称性がほぼ解消または逆転することが示されています。