超音速唤醒速度测量使用乙分子标记速度计
Applied optics
|August 12, 2025
概括
分子标记速度计精确测量高超音速流在球体后面醒来. 这种非侵入性激光诊断技术绘制了速度图,揭示了逆流和高精度的平均速度高达730m/s.
科学领域:
- 流体动力学 流体动力学
- 航空航天工程 航空航天工程
- 激光诊断 激光诊断 激光诊断
背景情况:
- 超音速流量研究对于航空航天应用至关重要.
- 了解物体背后的唤醒动态对于车辆设计至关重要.
- 对于高速流量,需要最少的侵入性测量技术.
研究的目的:
- 在高超音速条件下,使用分子标记速度测量 (MTV) 量化测量球体后续的速度.
- 将实验MTV数据与计算流体动力学 (CFD) 模拟进行比较.
- 评估MTV在高超音速流环境中的准确性和适用性.
主要方法:
- 使用分子标记速度测量 (MTV) 采用乙播种和脉冲 Nd:YAG 激光.
- 在超音速流程中对支架式和自由飞行球体进行了实验.
- 经过验证的实验结果与使用连续加勒金流溶解器与适应性网状精细化模拟的模拟相比.
主要成果:
- 观察到的逆流速度在 -105 和 65 m/s 之间,与模拟相一致.
- 在实验和模拟数据中,在剪切层外测量了730m/s的平均速度.
- 据估计,杆式和自由飞行情况的总平均不确定性为±4% (±35.5 m/s).
结论:
- MTV在超音速流动中提供了准确的定量速度映射.
- 该技术成功地捕获了复杂的流体特征,如逆流.
- MTV是高超音速研究的可行的非侵入性诊断工具.
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