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建立了计算托卡马克加料中弹丸消融的物理模型，结合1维输运模型编制了1.5维弹丸消融计算机模拟代码。使用ITER-FEAT的相关参数，对半径为6mm，初速度为2000m·s?1，从低磁场侧注入弹丸的消融速率进行了模拟计算。结果显示，弹丸消融速率先随注入深度而逐渐增大，最大消融速率约6×1026s?1，然后由于弹丸半径的减小，消融速率迅速减小，穿透深度约0.45m。这一结果与中性气体屏蔽模型(NGS)的结果一致，证明计算代码正确有效。同时，从计算结果反映出，对ITER这样的堆级托卡马克，采用常规弹丸注入方式，尽管速度高达2000m·s?1，穿透深度也远未达到等离子体中心，因此应采取其他有效措施来提高等离子体加料效率。

Theoretical model and numerical calculation of pellet ablation rate

A physical model of calculating the pellet ablation rate in tokamak fueling was proposed, which was combined with the 1-D transport model to develop the 1.5D pellet ablation code. Using the parameter of ITER-FEAT, the pellet ablation rate of radius 6mm with initial injection speed of 2000m•s^-1 when injecting from low field side was calculated. The results show that the ablation rate first increases gradually over time, then decreases rapidly because of decrement of pellet radius, the maximum ablation rate is about 6×10²⁶s^-1, the total penetration depth is about 0.45m. This result is consistent with that gained from the neutral gas shielding model (NGS), and it proved the validity of the code. At the same time, the calculation result indicate that, for the reactor grade tokamak such as ITER, using conventional pellet injection method, the penetration depth is small enough so that the core plasma fueling cannot be achieved although the injection speed is 2000m•s^-1. Therefore in order to raise the plasma fueling efficiency, other effective pellet injection scenario must be chosen.