Results from KSTAR powder injection experiments, in which tens of milligrams of boron nitride (BN) were dropped into low-power H-mode plasmas, show an improvement in wall conditions in subsequent discharges and, in some cases, a reduction or elimination of edge-localized modes (ELMs). Injected powder is distributed by the plasma flow and is deposited on the wall and, over the course of several discharges, was observed to gradually reduce recycling by 33%, and decrease both the ELM amplitude and frequency. This is the first demonstration of the use of BN for ELM mitigation. In all of these experiments, an Impurity Powder Dropper (IPD) was used to introduce precise, controllable amounts of the materials into ELMy H-mode KSTAR discharges. The plasma duration was between 10 s and 15 s, $I_p=500$ kA, $B_T=1.8$ T, $P_{\mathrm{NBI}}=1.6$ MW, and $P_{\mathrm{ECH}}=0.6$ MW. Plasma densities were between 2 and $3\times 10^{19}$ m⁻³. In all cases, the pre-fill and startup gas-fueling was kept constant, suggesting that the decrease in baseline D${}_{\alpha }$ emission is in fact due to a reduction in recycling. The results presented herein highlight the viability of powder injection for intra-shot and between-shot wall conditioning.

KSTAR 粉末注入实验的结果显示，在随后的放电中，将数十毫克的氮化硼 (BN) 滴入低功率 H 模式等离子体中，壁面状况有所改善，并且在某些情况下，边缘的减少或消除-本地化模式（ELM）。注入的粉末由等离子流分布并沉积在壁上，经过多次放电，观察到循环逐渐减少 33%，并降低 ELM 振幅和频率。这是使用 BN 进行 ELM 缓解的首次演示。在所有这些实验中，使用杂质粉末滴管 (IPD) 将精确、可控量的材料引入 ELMy H 模式 KSTAR 放电。等离子体持续时间在 10 秒到 15 秒之间，${\mathrm{一世}}_{磷}=500$ K a， ${乙}_{吨}=1.8$ , ${磷}_{\mathrm{国调局}}=1.6$ 兆瓦，和 ${磷}_{\mathrm{ECH}}=0.6$ 兆瓦。等离子体密度介于 2 和$3\times 10^{19}$ 米^-3。在所有情况下，预填充和启动气体燃料保持不变，表明基线 D 的减少${}_{\alpha }$排放实际上是由于回收的减少。此处呈现的结果突出了粉末注射在注射内和注射间壁调节方面的可行性。