Partially Relaxed Magnetohydrodynamic Equilibria with Bias-Flux Leakage Obtained in a Helicity-Driven Spheromak
Partially Relaxed Magnetohydrodynamic Equilibria with Bias-Flux Leakage Obtained in a Helicity-Driven Spheromak
复制标题
在螺旋驱动 Spheromak 中获得具有偏置磁通泄漏的部分松弛磁流体动力学平衡
DOI：
10.1143/jpsj.67.140
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发表时间：
1998
期刊：
影响因子：
--
通讯作者：
A. Kamitani
中科院分区：
文献类型：
--
作者：
T. Kanki;M. Nagata;T. Uyama;S. Ikuno;A. Kamitani
在磁通放大紧环实验中，偏置磁通能穿透磁通保护器的壁，是因为在磁通保护器产生球斑之前，偏置磁通已经开启了相当长的时间。采用有限差分法和边界元法相结合的新方法，数值计算了具有非常数λ（≡µ0 j·B / | B | 2）分布的螺度驱动球标的磁流体动力学平衡构型。其中µ0为真空磁导率，j为电流密度，B为磁场。计算结果表明，在I C / I P =0.4 （I C和I P分别表示线圈和等离子体的总电流）的情况下，由于整个空间的极向场减小，偏磁泄漏的影响导致整个安全系数q略有上升。然后，它们也引起分离矩阵内磁通量下降22.0%。
In the flux amplification compact torus experiment, the bias flux penetrates the wall of the flux conserver because it has been switched on a suitably long time prior to the production of a seed spheromak. The magnetohydrodynamic equilibrium configurations with a non-constant λ(≡µ 0 j · B / | B | 2 ) profile of a helicity-driven spheromak incorporating the situation of the bias-flux leakage out of the flux conserver are numerically determined by using the novel combination of the finite difference and the boundary element method. Here µ 0 , j and B are the permeability of vacuum, the current density and the magnetic field, respectively. The results of computations show that the effects of the bias-flux leakage cause a slight rise of the entire safety factor q in the case of I C / I P =0.4 ( I C and I P denote the total current of coil and plasma, respectively) because of the decrease in poloidal field over all space. Then, they also give rise to a 22.0% decrease in the magnetic flux inside the separatrix.