Calculations of axisymmetric stability of Tokamak plasmas with active and passive feedback
Calculations of axisymmetric stability of Tokamak plasmas with active and passive feedback
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DOI：
10.1006/jcph.1993.1022
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发表时间：
1993
影响因子：
4.1
通讯作者：
D. Ward;S. Jardin;C. Cheng
中科院分区：
文献类型：
--
作者：
D. Ward;S. Jardin;C. Cheng
摘要为了研究托卡马克等离子体轴对称模的反馈稳定，开发了一个新的线性MHD稳定性程序NOVA-W。NOVA-W代码是一个修改的非变分MHD稳定性代码NOVA，其中包括电阻性无源导体和有源反馈电路的影响。真空计算已重新制定的扰动极向通量，允许列入扰动环电流外的等离子体。等离子体-真空界面处的边界条件将不稳定位移与扰动极向通量联系起来。这使得线性MHD稳定性方程的反馈效应包括在内的解决方案。代码的被动稳定性预测已被测试对一个简化的分析模型和对一个现实的托卡马克配置不同的数值计算。比较结果证明了NOVA-W结果的准确性。对CIT托卡马克设计进行了主动反馈计算，证明了改变提供垂直位移测量的通量环的位置的效果。结果比较以及与那些计算较早使用效率较低的非线性代码。
Abstract A new linear MHD stability code, NOVA-W, has been developed in order to study feedback stabilization of the axisymmetric mode in deformable tokamak plasmas. The NOVA-W code is a modification of the non-variational MHD stability code NOVA that includes the effects of resistive passive conductors and active feedback circuits. The vacuum calculation has been reformulated in terms of the perturbed poloidal flux to allow the inclusion of perturbed toroidal currents outside the plasma. The boundary condition at the plasma-vacuum interface relates the instability displacement to the perturbed poloidal flux. This allows a solution of the linear MHD stability equations with the feedback effects included. The passive stability predictions of the code have been tested both against a simplified analytic model and against a different numerical calculation for a realistic tokamak configuration. The comparisons demonstrate the accuracy of the NOVA-W results. Active feedback calculations are performed for the CIT tokamak design demonstrating the effect of varying the position of the flux loops that provide the measurements of vertical displacement. The results compare well with those computed earlier using a less efficient nonlinear code.