一个PFEM的错误分析基于欧勒半隐含方案的不稳定的MHD方程
Kaiwen Shi1, Haiyan Su1, Xinlong Feng1
1College of Mathematics and System Sciences, Xinjiang University, Urumqi 830046, China.
Entropy (Basel, Switzerland)
|July 8, 2023
概括
本研究介绍了一种第一阶惩罚性有限元素方法 (PFEM),用于解决不可压缩的磁动力学 (MHD) 方程. 开发的数值方案证明了对不稳定的2D/3D问题的有效性.
科学领域:
- 计算流体动力学的流体动力学.
- 数字分析 数字分析
- 磁动力学是一种磁动力学.
背景情况:
- 不压缩磁动力学 (MHD) 方程由于其点性质而带来了挑战.
- 现有的方法可能会与不稳定的2D/3D MHD流的复杂性作斗争.
研究的目的:
- 为2D/3D不稳定的不可压缩MHD方程开发和分析一级惩罚有限元素方法 (PFEM).
- 严格推导出对拟议数值方案的错误估计.
主要方法:
- 使用惩罚方法来放松无分歧约束 (·u=0),转换问题.
- 采用欧勒半隐式方案,使用一阶倒数差异公式进行时间离散.
- 对于非线性术语,应用了半隐性处理.
主要成果:
- 成功地将角问题转化为两个较小,可解决的问题.
- 导出的严格错误估计取决于惩罚参数 (ε),时间步骤大小 (τ) 和网格大小 (h).
- 数字测试证实了拟议的PFEM计划的有效性.
结论:
- 一级惩罚有限元方法是解决不稳定的不可压缩的MHD方程的有效方法.
- 由此得出的误差估计为该方法的准确性提供了理论基础.
- 该方案为2D/3D MHD模拟提供了一个可行的数值工具.
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