FEB-E动态气靶偏滤器的研究

SYUDY OF THE DYNAMIC GAS TARGET DIVERTOR IN THE FEB-E

在 FEB- E设计阶段 ,偏滤器从开放式固定板靶优化为封闭式气体靶 ,以改善偏滤器的杂质控制和增加离子与气体的相互作用。通过喷气和注入杂质获得的部分脱靶等离子体形成了动态气体靶。喷气能降低删削层 (SOL)处等离子体温度 ,注入的杂质增加了 SOL处的辐射功率 ,使靶板的负载降低。用 NEWT1D编码模拟了 SOL处等离子体和杂质 (硼杂质 )的输运 ,得到了杂质、等离子体温度和等离子体密度分布。着眼于杂质的滞留和辐射 ,优化了喷气点的位置。用偏滤器靶板上热负载的减少量评估了硼杂质注入的效果。

In order to improve the impurity control and to increase the interaction of ions with neutral gas in the FEB divertor, the divertor is optimized to be the close type in the engineering design rather than the open one in the conceptual design. The partially detached plasma obtained by means of combination of gas puffing and impurity injection serves as a dynamic gas target. Puffing gas can reduce the plasma temperature in the scrape off layer (SOL). Injected impurity can increase the radiation power in SOL. Both of them make the heat load on the plate target smaller. The transport of plasma and impurity in SOL is simulated with NEWT1D code. Profiles of impurity (here is boron) and plasma temperature and plasma density are obtained. The position of puffing gas is optimized to be at the torus mid plane with the view of impurity retention and radiation in the SOL region. The effect of boron impurity injection is evaluated from the reduced heat load on the divertor target.