Simulation of Transient Transport Phenomena in Toroidal Plasmas

为了研究环形等离子体中的粒子输运和瞬变输运过程，我们开发了一个包含径向电场和等离子体旋转的输运模拟程序。包括新古典主义输运和湍流输运。在没有经验箍缩项的情况下，得到了稳定的密度分布。模拟再现了托卡马克实验中观察到的中性束注入过程中密度分布的变化，研究了欧姆等离子体中稳态密度分布与等离子体电流和等离子体温度的关系。中心密度近似与等离子体电流的平方成正比，与中心温度成反比。通过包括刮离层在内的输运分析，研究了粒子回收率、离子轨道损失和边缘温度对密度分布的影响。包括热输运在内的初步分析结果表明，中心加热使密度分布变平。对模拟程序进行了修改，加入了螺旋系统中等离子体所必需的环向粘性。研究了其对等离子体旋转和密度分布的影响，扩展了模拟程序，实现了与波分析程序和Fokker-Planck程序之间的模拟数据交换，以分析波加热和电流驱动。

In order to study the particle transport and transient transport processes in toroidal plasmas, we have developed a transport simulation code including radial electric field and plasma rotation. Neoclassical transport and turbulent transport are included. Without an empirical pinch term, stationary density profile was obtained. The modification of a density profile during neutral beam injection, which has been observed in tokamak experiments, was reproduced by the simulation.The dependence of the stationary density profile on the plasma current and the plasma temperature was studied in Ohmic plasmas. The central density is approximately proportional to the square of the plasma current and the inverse of the central temperature.The influence of particle recycling rate, ion orbit loss and edge temperature on the density profile was studied by the transport analysis including the scrape-off layr.The preliminary result of the analysis including heat transport shows flattening of the density profile by central heating.The simulation code was modified to include toroidal viscosity essential for plasmas in helical systems. The effect on the plasma rotation and density profile was studied.The simulation code was extended to exchange simulation data with the wave analysis codes and the Fokker-Planck code in order to analyze the wave heating and current drive.