在盖子旋转的稀化腔流中连续性的分解
Shesh N Dhurandhar1, Vishnu Mohan2, Manjul Sharma3
1Indian Institute of Technology Madras, Department of Aerospace Engineering, Tamil Nadu 600036, India.
Physical review. E
|June 19, 2025
概括
稀疏和可压缩性显著改变旋转腔中的流体流动,偏离标准模型. 这项研究揭示了反直觉的热传递,并突出了稀释气体动态中连续性假设的分解.
科学领域:
- 流体动力学 流体动力学
- 稀释气体的动态 稀释气体的动态
- 计算物理学的计算物理.
背景情况:
- 沃格尔-埃斯库迪耶 (VE) 流量描述了盖盖旋转腔动力学.
- 标准的纳维埃-斯托克斯-里埃 (NSF) 方程假设连续流.
- 在微/纳米尺度或高速流动中,稀释和压缩效应至关重要.
研究的目的:
- 调查稀释和压缩性对 VE 流量的影响.
- 分析 NSF 预测中的偏差.
- 确定连续分解的条件.
主要方法:
- 直接模拟蒙特卡洛 (DSMC) 方法.
- 开放FOAM计算流体动力学 (CFD) 软件.
- 通过Knudsen数 (Kn_ref) 0.0250.5和马赫数 (Ma_lid) 0.56.6进行模拟.
主要成果:
- 由于盖子旋转而导致不均的数字密度.
- 在超音速模式下,温度和速度滑动对马赫数不敏感.
- 通过NSF观察到反里埃热流和过度预测的剪切应力.
- 由局部克努森数 (Kn_g) 识别的连续分解的出现.
结论:
- DSMC模拟显示了 VE 流量与 NSF 预测的显著偏差.
- 稀释和压缩性导致变化的动量和热传输.
- 当地克努森数有效区分连续和稀疏流域.
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