载电流等离子体柱中电双层的产生机制

载电流等离子体柱由于外磁场压强大于其内部热压强，等离子体柱发生箍缩效应．该文从箍缩平衡理论及麦克斯韦方程出发，经严格推导得到了载电流等离子体柱中电场Ez(z，r)的分布．从表达式Ez(z，r)可看出，电双层已经形成，在z=I／2时Ez(z，r)达到极值．通过数值模拟，给出了电双层沿对称轴的轴向电势分布，它与Toryen和Lindber基于实验基础上给出的电双层电势分布的变化趋势是一致的．

Formatting Double Layer Mechanism in Plasma Cylinder Carrying Electric Current

The pinch-effect will occur in plasma column because magnetic field pressure outside is bigger than thermal pressure inside of the plasma column carrying electric current. In this paper, based on the pinch balance theory and Maxwell equation, the distribution of the electric field E_z(z,r) in plasma column has been obtained. From the expression of the electric field E_z(z,r), it can be known that the double layer has been formed. Its maximum will emerge at z=L/2. Using the method of numerical simulation, we obtained the distribution of the double layer voltage.