离子温度梯度模湍流扩散特性的量化描述  

Quantitative description of the spreading properties in ion temperature gradient driven turbulence

作　　者：田辉 李继全[1] TIAN Hui;LI Ji-quan(Southwestern Institute of Physics,Chengdu 610041)

机构地区：[1]核工业西南物理研究院,成都610041

出　　处：《核聚变与等离子体物理》2024年第3期343-350,共8页Nuclear Fusion and Plasma Physics

基　　金：国家自然科学基金(U1967206)。

摘　　要：采用回旋动理学模型对无剪切平板位形中离子温度梯度模(ITG)湍流扩散的物理特性进行了数值模拟研究。提出了湍流有效扩散距离的描述方法,定量地讨论了湍流扩散性质对磁场位形因子和离子温度梯度特征长度的依赖关系。结果显示,随着极向磁场的减小,湍流扩散增强;随着离子温度梯度特征长度的增加,湍流扩散减弱。更重要的是,通过对比ITG和ETG湍流以及不同碰撞阻尼下的ITG湍流中的湍流扩散特征,论证了带状流对ITG湍流扩散的影响。模拟结果表明,在此模型下,带状流对湍流扩散具有明显的抑制作用。The spreading properties of ion temperature gradient(ITG)driven turbulence in a shearless slab geometry are numerically simulated by using the gyrokinetic model.A quantitative description method on the turbulence spreading is proposed by defining the effective turbulence spreading distance.The parametric dependence of turbulence spreading properties on the magnetic field configuration factor and the characteristic length of ion temperature gradient is quantitatively discussed.The results show that the intensity of turbulence spreading increases with the decrease of the poloidal magnetic field.As the characteristic length of ion temperature gradient increases,turbulence spreading weakens.Particularly,the role of zonal flows in turbulence spreading is investigated by comparing the spreading characteristics in ITG and ETG turbulence and ITG turbulence under different collision damping.The simulation results show that zonal flows have a significant suppression effect on turbulence spreading under the model discussed in this paper.

关 键 词：湍流扩散 带状流 回旋动理学模拟 

分 类 号：O533[理学—等离子体物理] O534[理学—物理]