Equilibrium analysis of free boundary MHD plasma with bootstrap current

为了实现托卡马克型核聚变反应堆的稳态运行，有一种方法是利用新经典输运理论中的自举电流，这种自举电流是由等离子体的热力学驱动的。这意味着等离子体本身可以长期维持环向电流。自由边界等离子体的数值MHD平衡程序是在1993年开发的。我们比较了几种粘度模型，并将赫希曼有理近似应用于本文的分析。1994年，利用数值计算程序进行了以下分析。采用Hirshman粘性模型迭代计算，将自举电流与欧姆电流和反磁电流进行了比较。自举电流更多地流经等离子体表面而不是等离子体中心。这就是为什么等离子体压力梯度变小，捕获粒子之间在等离子体中心附近没有动量交换的原因。在环向电流Ip=22(MA)和15(MA)的情况下，由于极向磁场的作用，15(MA)的自举电流比22(MA)的大。对等离子体密度与温度的关系也进行了研究，并利用摩擦和粘度矩阵进行了考虑杂质影响的进一步分析。

In order to realize steady-state operations in tokamak-type nuclear fusion reactors, there is the method to use bootstrap currents form neoclassical transport theory, which are driven by the thermodynamic force of plasma. This means that plasma itself can sustain the toroidal current for long time.Development of the numerical MHD equilibrium code for free boundary plasma was carried out in 1993. We have compared several viscosity models and applied the Hirshman's rational approximations to the present analysis. In 1994, following analyzes were carried out by using the the numerical code. The bootstrap currents were compared with Ohmic and diamagnetic currents using iterative calculation with Hirshman's viscosity model. The bootstrap currents flow near the plasma surface more than at the center of plasma. That is why the plasma pressure gradient becomes low and no momentum exchange among trapped particles happen near the center of plasma. In comparison of the case with toroidal current Ip=22 (MA) and 15 (MA), ratio of the bootstrap currents of 15 (MA) is larger than that of 22 (MA) because of the poloidal magnetic field. Study for relation between plasma density and temperature was also carried out.Further analysis under consideration of the effects of impurity will be carried out by using the friction and viscosity matrix in the near future.