对于冲击波的非平衡效应的中镜动力学方法
Ruofan Qiu1, Xinyuan Yang1, Yue Bao1
1School of Aerospace Engineering, Xiamen University, Xiamen 361005, China.
Entropy (Basel, Switzerland)
|March 28, 2024
概括
这项研究使用分子动力学来探索冲击波中的不平衡效应. 它揭示了分子运动如何影响冲击波特征,提供了一个超越传统流体动力学的中视镜视角.
科学领域:
- 流体动力学 流体动力学
- 分子动力学分子动力学
- 航空航天工程 航空航天工程
背景情况:
- 冲击波在高速飞机和发动机开发中至关重要.
- 传统的计算流体动力学 (CFD) 使用宏观变量 (马赫数,压力,密度,温度).
- 冲击波的厚度接近分子自由路径,使分子运动具有影响力.
研究的目的:
- 介绍不平衡效应方法的理论和理解.
- 审查与冲击有关的现象中不平衡行为的研究进展.
- 从分子运动层面探索冲击波物理.
主要方法:
- 解决博尔兹曼-巴特纳格-格罗斯-克鲁克 (博尔兹曼BGK) 或多重放松时间博尔兹曼 (MRT-博尔兹曼) 方程.
- 获得分子速度分布函数的不平衡时刻.
- 分析流体动力学中不平衡时刻的作用和物理意义.
主要成果:
- 不平衡效应方法提供了与宏观变量不同的冲击波特征的描述.
- 没有平衡的时刻会影响宏观流体控制方程.
- 中镜动力学方法在诸如里曼问题,冲击反射和爆炸波等冲击问题中揭示了不平衡行为.
结论:
- 不平衡效应方法提供了对冲击波的中观视角,与传统的宏观视角不同.
- 这种方法在分析冲击现象方面具有重要的应用潜力.
- 了解分子运动是全面了解冲击波的关键.
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