计算物理 ›› 2025, Vol. 42 ›› Issue (2): 202-210.DOI: 10.19596/j.cnki.1001-246x.8858

• 研究论文 • 上一篇    下一篇

辐射, 电子和离子能量方程组耦合计算的二阶时间精度分裂算法

李双贵(), 杨容   

  1. 北京应用物理与计算数学研究所, 北京 100094
  • 收稿日期:2023-11-01 出版日期:2025-03-25 发布日期:2025-04-08
  • 作者简介:

    李双贵, 博士, 副研究员, 从事辐射输运计算方法与数值模拟工作, Email:

  • 基金资助:
    国家自然科学基金(12101067); 国家自然科学基金(12035002)

Coupling Radiation, Ion and Electron Energy Equations with Second-order Time Discretization

Shuanggui LI(), Rong YANG   

  1. Institute of Applied Physics and Computational Mathematics, Beijing 100094, China
  • Received:2023-11-01 Online:2025-03-25 Published:2025-04-08

摘要:

采用二阶向后微分公式时间离散, 分别耦合迭代算子分裂方法和微分算子分裂方法, 构造辐射输运和电子、离子能量方程组二阶时间精度离散方法。采用相同时间精度离散格式, 迭代算子分裂方法数值误差小于微分算子分裂方法。与一阶向后Euler时间离散方法比较, 数值解误差相当时, 二阶时间精度的迭代算子分裂方法时间步长大一个量级, 计算量几乎没有增加, 程序实现容易且健壮性好, 可有效提高ICF物理模型数值模拟的计算效率。

关键词: 辐射输运, 3T(电子、离子和辐射)模型, 二阶时间精度, 迭代算子分裂方法, 微分算子分裂方法

Abstract:

Based on second-order time discretization of BDF2, this paper presents a simpler approach for designing algorithms for coupling radiation, ion and electron energies via operator splitting method. Numerical results show the error and computational cost of iterative operator splitting method is less than that of operator splitting method with the same time discretization order, and while compared with first-order backward Euler method, time steps of second-order BDF2 can be ten times lager for obtaining the same computational accuracy. This new proposed second-order time discretization iterative operator splitting method can be used for simulating ICF physical models, and promoting the computational efficiency.

Key words: radiative transfer, three-temperature (electron; ion; and radiation) model, second-order time discretization, iterative operator splitting method, operator splitting method