Wang Shaojie
Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui, 230031, China.
Phys Rev Lett. 2004 Oct 8;93(15):155007. doi: 10.1103/PhysRevLett.93.155007.
It is found that, with a model current profile, the Grad-Shafranov equation can be reduced to the Helmholtz equation, which can describe a variety of equilibrium configurations. With the eigenvalue problem solved in the toroidal coordinate system, an analytical solution to the Grad-Shafranov equation is found. It is demonstrated that current reversal equilibrium configurations exist with finite radial gradient of plasma pressure and continuous current density, and that current density reversal is accompanied by pressure gradient reversal.
研究发现，对于一个模型电流分布，Grad-Shafranov方程可简化为亥姆霍兹方程，该方程能够描述多种平衡构型。通过在环形坐标系中求解本征值问题，得到了Grad-Shafranov方程的解析解。结果表明，存在具有有限等离子体压力径向梯度和连续电流密度的电流反转平衡构型，并且电流密度反转伴随着压力梯度反转。
