Collisional delta-f scheme with evolving background for transport time scale simulations
Collisional delta-f scheme with evolving background for transport time scale simulations
复制标题
具有演化背景的碰撞 delta-f 方案用于传输时间尺度模拟
DOI：
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发表时间：
1999
期刊：
影响因子：
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通讯作者：
J. Krommes
中科院分区：
文献类型：
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作者：
S. Brunner;E. Valeo;J. Krommes
δf 方法被扩展用于模拟碰撞等离子体中近麦克斯韦分布的输运时间尺度演化。这涉及同时推进用于表示固有动力学分量 δf 的加权标记粒子，以及用于偏移麦克斯韦背景 fSM 参数的流体方程。详细解决了碰撞 δf 算法中由于标记粒子权重扩散而导致数值噪声增加的问题，并提出了该问题的解决方案。为了在相空间的关键区域获得更高的分辨率，开发了一种用于实现标记粒子源和汇的实用程序。作为原理证明，这套方法用于计算斯皮策电导率以及均匀等离子体中的碰撞吸收。
The δf approach is extended for simulating the transport time-scale evolution of near-Maxwellian distributions in collisional plasmas. This involves simultaneously advancing weighted marker particles for representing the intrinsically kinetic component δf, and fluid equations for the parameters of the shifted Maxwellian background fSM. The issue of increasing numerical noise in a collisional δf algorithm, due to marker particle weight spreading, is addressed in detail, and a solution to this problem is proposed. To obtain higher resolution in critical regions of phase space, a practical procedure for implementing sources and sinks of marker particles is developed. As a proof of principal, this set of methods is applied for computing electrical Spitzer conductivity as well as collisional absorption in a homogeneous plasma.