Control of edge electric field by fast neutral beam injection

点击翻译按钮获取中文摘要

(1)We have modified the simulation codes for fast ion orbit and radial electric field and calculated the radial electric field modified by fast neutral beam injection(NBI) in medium and large size tokamaks.Results obtained are;(1) We have obtained two kinds of radial ion losses(direct orbit loss and charge exchange loss, and radial momentum loss induced by toroidal NBI) and have shown that a large amount of radial ion losses are generated by localized NBI at the edge.(2) Radial electric field changes with NBI to maintain the radial ambipolar condition. It is shown that the radial electric field of 50 V/cm is induced by localized NBI of about 100 kW.(3) In future, a modification of the code that the realistic transport model ,such as the extraordinary transport must be taken account in the present calculation.(2)It is shown that the oscillating radial electric field(Er) of about 30 V/cm can be generated by the AC limiter bias experiment up to 100 kHz. The additional oscillating poloidal electric field(Ep) is generated by the oscillating Er. This oscillating Ep is possible to modify the radial particle transport.