对于不可压缩的流量而言,离散的统一气体运动方案
1China Aerodynamics Research and Development Center, National Key Laboratory of Aerospace Physics in Fluids, Mianyang, Sichuan 621000, China and Hypervelocity Aerodynamics Institute, Mianyang, Sichuan 621000, China.
Physical review. E
|October 21, 2025
概括
改进的离散统一气体运动方案 (DUGKS) 提高了数值稳定性和效率. 这种新的DUGKS版本在流体动力学模拟中实现了更快的融合和更高的精度.
科学领域:
- 计算流体动力学 计算流体动力学
- 数字分析 数字分析
- 动力学理论 动力学理论
背景情况:
- 离散统一气体运动方案 (DUGKS) 是一种用于解决运动方程的数值方法.
- 现有的DUGKS版本在数值稳定性和计算效率方面存在局限性.
研究的目的:
- 提出一个改进的离散统一气体运动方案 (DUGKS),增强数值稳定性,准确性和效率.
- 在具有挑战性的流动场景中解决以前的DUGKS方法的融合问题.
主要方法:
- 改进的DUGKS使用梯形规则进行碰撞项集成,并引入辅助分布函数.
- 它采用一个矩形规则来实现隐式对流术语集成,并结合了梯形规则和泰勒扩展来进行接口流量评估.
- 隐式处理对流量和优化流量计算有助于提高性能.
主要成果:
- 与原始和优化的DUGKS版本相比,改进的DUGKS表现出明显更好的数值稳定性.
- 它实现了更快的融合,需要更少的代步骤和更少的计算时间.
- 保持精度,在Couette流和泰勒-格林流模拟中减少错误.
- 该方案成功地对低分辨率网格和高雷诺兹数进行了融合,而以前的方法失败了.
结论:
- 改进的DUGKS在动力图的数值稳定性,精度和计算效率方面取得了实质性的进步.
- 它的隐式处理和精细的接口流量评估扩大了稳定区域,使得在以前难以处理的条件下进行模拟.
- 这种增强的DUGKS是复杂的流体动力学问题的更强大和更有效的工具.
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