在空间发展的可压缩的动边界层中,动-非动接口
Feng Liu1,2,3, Ze Yang2,3, Pengfei Lv2,3
1Nanjing University of Science and Technology, School of Energy and Power Engineering, Nanjing 210094, China.
Physical review. E
|August 1, 2025
概括
直接的数值模拟揭示了可压缩边界层中的动-非动接口 (TNTI). 主要发现详细介绍了TNTI层厚度和能量转移动态,这对于预测流至关重要.
科学领域:
- 流体动力学 流体动力学
- 流研究 流研究
- 计算流体动力学的流体动力学.
背景情况:
- 动-非动接口 (TNTI) 是动流动中的一个关键区域,影响混合和阻力.
- 了解TNTI的结构和动态对于准确建模空间发展的乱边界层至关重要.
- 以前的研究已经提供了洞察力,但对可压缩边界层的详细分析仍然是一个活跃的领域.
研究的目的:
- 在空间发展的可压缩乱边界层中研究乱-非乱接口 (TNTI) 的特征.
- 量化TNTI层及其组成部分 (粘性上层和流性下层) 的平均厚度.
- 分析不同方向跨越TNTI的跨尺度能量传输机制.
主要方法:
- 使用直接数值模拟 (DNS) 来捕捉流的细度结构.
- 分析的重点是TNTI的平均厚度,粘性上层 (δ_{VSL}) 和动子层 (δ_{TSL}).
- 使用多尺度分析来检查跨尺度的能量传输 (T_{r_{1}}和T_{r_{2}}) 正常和接触到接口.
主要成果:
- 平均TNTI层厚度 (δ_{TNTI}) 发现大约为13η_{ref},其中 δ_{VSL} ≈3.6η_{ref} 和 δ_{TSL} ≈9.4η_{ref}.
- 对TNTI (T_{r_{1}}) 进行的跨尺度能量转移正常发生,从大到小尺度.
- 能量转移正常到接口 (T_{r_{2}}) 显示了一个相反的趋势,从小到大尺度,在触角方向有不同的行为.
结论:
- 该研究提供了关于TNTI在可压缩流边界层中的结构和能量转移动态的详细定量数据.
- 这些发现提供了宝贵的洞察力,了解了乱-非乱界面上的能量转移的多尺度性质.
- 这些结果预计将有助于开发更准确的模型来预测空间发展的流.
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