液滴在颗粒层内渗透流动动态过程的激光荧光实验测量  

Experimental measurement of the penetration of a droplet into a granular medium using laser and fluorescence

作　　者：钟哲晗 卓建坤[1] 姚强[1,2] ZHONG Zhe-han;ZHUO Jian-kun;YAO Qiang(Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China;Department of Energy and Power Engineering, School of Electric Engineering, Xinjiang University, Urumqi 830046, China)

机构地区：[1]清华大学热科学与动力工程教育部重点实验室,北京100084 [2]新疆大学电气工程学院能源与动力系,新疆乌鲁木齐830046

出　　处：《光学精密工程》2020年第7期1446-1453,共8页Optics and Precision Engineering

基　　金：“十三五”国家重点研发资助项目(No.2018YFB0605000)。

摘　　要：为了实现下落液滴在颗粒层内渗透流动的三维快速测量,本文开发了一种基于激光-荧光-高速相机的光学测量系统,用以拍摄记录不同时刻颗粒层内液体的分布形貌。该系统由三个部分组成,首先,液滴和颗粒层在撞击渗透系统中接触,采用折射率匹配方法减少光学散射;其次,光学信号采集系统拍摄记录颗粒层内液体的形貌分布随时间的变化,通过改变拍摄截面,可以实现准三维测量;最后,在数据处理系统中使用Matlab程序完成对实验数据的分析,可以获得液体在层内不同方向上距离、速度和加速度的时空分布,进一步为流体在颗粒层渗透时的受力、动量和能量变化的动态理论模型的建立和验证提供支撑。实验系统的空间分辨率达到0.02 mm,时间分辨率达到0.5 ms,满足渗透过程测量稳定可靠、高时空分辨率的要求。To analyze the fast penetration of a 3D droplet into a granular medium and its flow,an optical measuring system comprising a laser,fluorescence,and a high-speed camera has been developed.The system consists of three parts the penetration segment,wherein droplets contact a medium,adding index-matched fluids to reduce light scattering;the optical signal acquisition segment,which captures the liquid morphology in the medium at different conditions and performs a quasi-3D measurement using laser sheets;and the data processing segment,which analyzes experimental data.The moving distance,speed,and acceleration of the droplet in diverse directions at different times are measured to describe such dynamic process.Moreover,the data can support the establishment and verification of the dynamic theory,comprising force,momentum,and energy.The spatial resolution of this system is 0.02 mm,and its time resolution is 0.5 ms.They can address requirements such as real time,strong stabilization,and high spatial and desired time resolutions.

关 键 词：光学测量 激光荧光 液滴 颗粒层 撞击 渗透 

分 类 号：TK11[动力工程及工程热物理—热能工程]