梯度-强大的混合 DG Discretizations 对于可压缩的冲压方程
1Department of Applied Mathematics, University of Twente, Hallenweg 19, 7522NH Enschede, Netherlands.
概括
这项研究为可压缩的斯托克斯方程提出了两种混合不连续的加勒金 (HDG) 方法. 一种方法确保了收性,非负性和梯度稳定性,用于准确的流体模拟.
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
- 部分微分方程部分微分方程.
背景情况:
- 可压缩的斯托克斯方程模型流体流动与密度变化.
- 准确的数值方法对于模拟平衡的流体状态至关重要.
- 梯度强度可以提高水静平衡场景的准确性.
研究的目的:
- 为了研究两个混合不连续的加勒金 (HDG) 离散式,用于可压缩的斯托克斯方程.
- 评估基于趋同,密度非负性,质量约束和梯度强度的方法.
- 为了证明这些方法对平衡和非水静态状态的有效性.
主要方法:
- 开发和分析两个HDG方案用于速度密度公式.
- 一个方案利用一个符合速度的替代空间.
- 另一个方案采用完全不连续的方法.
- 介绍了这两个方案的更高层次的扩展.
主要成果:
- 符合HDG的方案满足所有所需的特性,包括梯度强度.
- 完全不连续的HDG方案满足了除梯度强度外的所有属性.
- 数字基准验证了两个更高层次的方案的表现.
- 展示了梯度强度对于非水静态平衡状态的重要性.
结论:
- 符合HDG的方法为可压缩流体流动提供了强大而准确的方法.
- 梯度强度对于准确捕捉平衡的流体动力学是必不可少的.
- 提出的方法适用于斯托克斯方程和纳维尔-斯托克斯方程.
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