改善ITER 弹丸注入芯部加料的研究

研究了五种不同组合的固态氢同位素靶丸H₂、HD、D₂、DT 和T₂ 在聚变等离子体中的消融率。结果表明, 燃料靶丸的同位素效应, 可导致更深的靶丸消融物质沉积。在同样的本底等离子体条件和弹丸初始参数下, 注入氚丸比氢丸的穿透深度增加约40%。适度减轻一些ITER 的加料困难。进一步的研究表明从中平面高场侧注入靶丸对芯部加料有显著改善。考虑托卡马克非均匀磁场的影响, 被电离的消融云内的垂直漂移电流产生极化, 引起带电消融物沿大半径方向朝外漂移。数值模拟计算表明, 只要用初始速度为每秒几百米的低速弹丸, 便能使靶丸的消融物质沉积到ITER 等离子体中心。

Study of improving core fueling with pellet injection in ITER

The influence of isotope on ablation rates concerning the material mass M_i, sublimation energy U_m and molecular density n_m, for five combinations of solid isotopic hydrogenic pellets H_2, HD, D_2, DT, T_2 have been studied. The results show that injection with the DT or T_2 fuelling pellet leads to deeper pellet material deposition. Under the same plasma condition and initial pellet parameters, the penetration depth for tritium pellet increases by 40% in comparison with that of hydrogen pellet. The ITER core fueling difficulty will be moderately alleviated by taking the isotope effects into account. The significant improvement of core fueling with pellet injection from high field side (HFS) in the mid-plane has been presented. By considering the effect of non-uniform tokamak magnetic field, the vertical drift current inside the ionized ablatent produces the polarization that causes the charged ablatant drifts in the direction of the outward major radius. Numerical simulation calculations show that the ablated substance of pellet can be deposited to the core region even with the initial velocity of pellet as low as a few hundred meters per second.