arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1010.0108physics.comp-phcs.NAmath.NAphysics.plasm-ph
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等离子体中库仑相互作用的直接模拟蒙特卡罗方案

Direct simulation Monte Carlo schemes for Coulomb interactions in plasmas

Université de Toulouse(图卢兹大学;UPS,INSA,UT1,UTM;图卢兹数学研究所);UPS, INSA, UT1, UTM(加州大学洛杉矶分校数学系);Institut de Mathématiques de Toulouse(费拉拉大学数学系和CMCS);Mathematics Department, University of California, Los Angeles (UCLA);Mathematics Department and CMCS, University of Ferrara

Giacomo Dimarco, Russell Caflisch, Lorenzo Pareschi

AI总结:

本文通过推广Bird和Nanbu-Babovsky的稀薄气体动力学算法到库仑相互作用,基于Bobylev和Nanbu的近似玻尔兹曼算子,提出了两种直接模拟蒙特卡罗方案,并进行了误差分析和数值验证。

摘要:

我们考虑开发用于具有库仑相互作用的分子系统的蒙特卡罗方案。借助Bobylev和Nanbu引入的近似(气体和等离子体碰撞算法的理论,基于玻尔兹曼方程和Landau-Fokker-Planck方程,Physical Review E, Vol. 61, 2000),我们将Bird和Nanbu-Babovsky的经典稀薄气体动力学算法推广到库仑情况。因此,方案不是基于原始的玻尔兹曼碰撞算子,而是通过使用近似的玻尔兹曼算子构建。上述选择允许在模拟中使用更大的时间步长;此外,避免了昂贵的接受-拒绝碰撞过程,并且每个粒子都参与碰撞。进行了误差分析以及与原始Bobylev-Nanbu (BN)方案的比较。数值结果显示,近似玻尔兹曼算子的理论收敛速率与数值结果一致,并且Bird型方案相对于原始方案具有更好的性能。

英文摘要:

We consider the development of Monte Carlo schemes for molecules with Coulomb interactions. We generalize the classic algorithms of Bird and Nanbu-Babovsky for rarefied gas dynamics to the Coulomb case thanks to the approximation introduced by Bobylev and Nanbu (Theory of collision algorithms for gases and plasmas based on the Boltzmann equation and the Landau-Fokker-Planck equation, Physical Review E, Vol. 61, 2000). Thus, instead of considering the original Boltzmann collision operator, the schemes are constructed through the use of an approximated Boltzmann operator. With the above choice larger time steps are possible in simulations; moreover the expensive acceptance-rejection procedure for collisions is avoided and every particle collides. Error analysis and comparisons with the original Bobylev-Nanbu (BN) scheme are performed. The numerical results show agreement with the theoretical convergence rate of the approximated Boltzmann operator and the better performance of Bird-type schemes with respect to the original scheme.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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