Comparison between kinetic and fluid simulations of slab ion temperature gradient driven turbulence
Comparison between kinetic and fluid simulations of slab ion temperature gradient driven turbulence
复制标题
板条离子温度梯度驱动湍流的动力学和流体模拟比较
DOI：
10.1063/1.1544664
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发表时间：
2002
影响因子：
2.2
通讯作者：
W. Horton
中科院分区：
文献类型：
--
作者：
H. Sugama;Tomo;W. Horton
对无碰撞板离子温度梯度驱动湍流的动力学和流体模拟进行了详细的比较。由Sugama， Watanabe和Horton提出的线性不稳定模的非耗散闭包模型（NCM）[物理学]。等离子体8,2617(2001)]，以及hamett和Perkins （HP）的耗散闭合模型[物理学报]。Rev. Lett. 64, 3019(1990)]在单独的流体模拟中使用。通过将流体模拟的非线性结果与高精度的无碰撞动力学模拟结果进行比较，验证了这些闭合模型定量预测湍流热输运的有效性。仿真结果表明，在饱和湍流状态下，HP模型得到的湍流热扩散系数χ明显大于NCM给出的χ， NCM更接近于动力学模拟中测量的χ。与HP模型中假设的平行热流密度闭合关系的耗散形式相反，NCM很好地描述了热流密度。
A detailed comparison between kinetic and fluid simulations of collisionless slab ion temperature gradient driven turbulence is made. The nondissipative closure model (NCM) for linearly unstable modes, which is presented by Sugama, Watanabe, and Horton [Phys. Plasmas 8, 2617 (2001)], and the dissipative closure model by Hammett and Perkins (HP) [Phys. Rev. Lett. 64, 3019 (1990)] are used in separate fluid simulations. The validity of these closure models for quantitative prediction of the turbulent thermal transport is examined by comparing nonlinear results of the fluid simulations with those of the collisionless kinetic simulation of high accuracy. Simulation results show that, in the saturated turbulent state, the turbulent thermal diffusivity χ obtained from the HP model is significantly larger than the χ given by the NCM which is closer to χ measured in the kinetic simulation. Contrary to the dissipative form of the parallel heat flux closure relation assumed in the HP model, the NCM describes well t...