Drift kinetic and gyrokinetic theories and simulations are powerful means for quantitative predictions of neoclassical and anomalous transport fluxes in helical systems such as the Large Helical Device (LHD). The δf Monte Carlo particle simulation code, FORTEC-3D, is used to predict radial profiles of the neoclassical particle and heat transport fluxes and the radial electric field in helical systems. The radial electric field profiles in the LHD plasmas are calculated from the ambipolarity condition for the neoclassical particle fluxes obtained by the global simulations using the FORTEC-3D code, in which effects of ion or electron finite orbit widths are included. Gyrokinetic Vlasov simulations using the GKV code verify the theoretical prediction that the neoclassical optimization of helical magnetic configuration enhances the zonal flow generation which leads to the reduction of the turbulent heat diffusivity χ i due to the ion temperature gradient (ITG) turbulence. Comparisons between results for the high ion temperature LHD experiment and the gyrokinetic simulations using the GKV-X code show that the χ i profile and the poloidal wave number spectrum of the density fluctuation obtained from the simulations are in reasonable agreements with the experimental results. It is predicted theoretically and confirmed by the linear GKV simulations that the E × B rotation due to the background radial electric field E r can enhance the zonal-flow response to a given source. Thus, in helical systems, the turbulent transport is linked to the neoclassical transport through E r which is determined from the ambipolar condition for neoclassical particle fluxes and influences the zonal flow generation leading to reduction of the turbulent transport. In order to investigate the E r effect on the regulation of the turbulent transport by the zonal flow generation, the flux-tube bundle model is proposed as a new method for multiscale gyrokinetic simulations.
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机译：漂移动力学和陀螺动力学理论和模拟是定量预测诸如大型螺旋装置（LHD）之类的螺旋系统中新古典和异常输运通量的有力手段。 δf蒙特卡洛粒子模拟代码FORTEC-3D用于预测螺旋系统中新古典粒子的径向分布和热传输通量以及径向电场。 LHD等离子体中的径向电场分布是通过使用FORTEC-3D代码通过全局模拟获得的新古典粒子通量的双极性条件计算得出的，其中包括离子或电子有限轨道宽度的影响。使用GKV代码进行的陀螺动力学Vlasov模拟验证了理论预测，即新古典优化的螺旋磁性构型可增强纬向流产生，从而由于离子温度梯度（）降低湍流热扩散率χ分布和极谱数谱是合理的与实验结果一致。从理论上预测并通过线性GKV模拟证实，由于背景径向电场E r 引起的E×B旋转可以增强对给定源的纬向流响应。因此，在螺旋系统中，湍流输运通过E r 与新古典输运相关联，E r 由新古典粒子通量的双极性条件确定，并影响带状流的产生，从而导致湍流输运的减少。为了研究E r 对地带流产生对湍流输运的调节作用，提出了通量管束模型作为多尺度陀螺动力学模拟的一种新方法。
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