托卡马克能量约束及自举电流效应的初步考虑

基于Lee等人的离子温度梯度模导致的反常热能输运系数,本文研究了辅助加热托卡马克等离子体的能量约束行为,并对自举电流的效应作了初步考虑。结果表明,计算得到的能量约束时间随等离子体电流I_p和托卡马克大半径R增大而增长,随注入功率P_t、环向场B_t以及等离子体小半径α的增大而缩短。这些结果与Kaye-Goldston的经验约束定标具有相同的趋势。自举电流的存在总是导致能量约束时间的增加,当自举电流与总电流的比值γ较小时,能量约束时间的增加率约为γ/2。此外,自举电流将造成锯齿反转半径的减小。     

EFFECTS OF BOOTSTRAP CURRENT ON ENERGY CONFINEMENT OF TOKAMAK PLASMAS

Based on the principle of profile consistency and η_i-mode induced anomalous transport model, the enery confinement in tokamak plasmas is studied with inclusion of the bootstrap curreut in which the poloidal magnetic field is consistently deter-mined. The results show that bootstrap current has a significant effect on plasma confinement. If the bootstrap current is (15-30)% of the total current, global energy confinement time may increase by (20-45)%, and the maximum of related energy store is almost as much as twice the value without bootstrap current. Variation of the energy confinement time with the plasma parameters is of similar trend with Kaye-Goldston scaling. In addition, it can be seen that the radius of q=l surface decreases with bootstrap current, which may be one of the possible mechanisms for some experimental results where sawtooth oscillation disappears because of auxiliary heating.     

电磁涨落场引起的反常自举电流的准线性估计

本文研究了电磁涨落场产生的反常自举电流,得到了在低等离子体碰撞频率下该电流的一些重要特征。我们将所得到的反常自举电流与新经典理论预言的结果进行了比较,并讨论了反常自举电流与实验观测之间的可能联系。