事件触发的以背景为导向的schlieren:高频可视化加热喷气流的高频可视化
Optics letters
|May 15, 2024
概括
一种新的事件触发的面向背景的Schlieren (EBOS) 技术以低成本提供连续的,高率的流动可视化. 这种方法准确地测量温度分布,并捕获流结构.
科学领域:
- 流体动力学 流体动力学
- 光学诊断仪器的使用.
- 流动可视化 流动可视化
背景情况:
- 传统的高率背景导向光学 (BOS) 技术的运行时间很短.
- 需要持续的,具有成本效益的流动可视化方法,能够实现高率.
研究的目的:
- 引入和验证一个新的事件触发的面向背景的Schlieren (EBOS) 技术.
- 为了证明EBOS对连续,高率流量测量的能力.
- 评估EBOS在描述流动力学方面的准确性和适用性.
主要方法:
- 开发一个由事件触发的BOS系统,结合了由事件触发的摄像头和脉冲激光斑点投影.
- 使用脉冲激光光斑投影的事件数据重建BOS图像.
- 处理BOS图像以确定流密度和温度分布.
主要成果:
- 该EBOS技术可实现连续可视化和记录以每秒千 (kFPS) 率的流量.
- 热气枪的温度测量显示与热电偶数据一致,在10.8%的误差范围内.
- 该技术成功地捕捉了喷气温度的演变超过150秒,并可视化了不稳定的流结构.
结论:
- 开发的EBOS技术为连续,高率的流动可视化提供了具有成本效益的解决方案.
- EBOS准确地测量温度分布和动态流体结构,克服了现有的BOS方法的局限性.
- 这种技术为研究流体流中的短暂和动荡现象开辟了新的可能性.
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