ENDGAME - Laboratory Experiment 2024-01-16 Exp. 005 - High Speed Camera data

Shock-tube experiments in combination with high speed Schlieren shadow photography. The shocktube setup consists of a high-pressure reservoir connected with a cylindrical tube through a diaphragm pulse valve which allows a fast release of pressurized gas into the ambient pressure tube. The high-pressure reservoir is filled with compressed air at a given overpressure with respect to ambient pressure (up to 8 bar). The pipe was either empty (i.e. with air at ambient conditions) or filled with a given amount of small particles. We adopted pipes an inner diameter of 4 cm and different lengths (20, 30 and 80 cm). We also considered different volumes of pressurized gas (~650 cm3 and ~1550 cm3). A pressure sensor has been placed at the vent of the conduit to record pressure variations during experiments. Images from the high speed camera were collected at a frame rate of 30000 fps. When the valve is open, a jet flow is produced, with shock and acoustic waves propagating in the atmosphere, which become visible due to the high speed Schlieren shadow photography.本数据集的实验数据源自激波管（Shock-tube）实验结合高速纹影阴影摄影（Schlieren shadow photography）技术。 激波管实验装置由高压储气罐与圆柱形管段组成，二者通过膜片脉冲阀连接，该阀可快速将高压气体释放至常压管段内。高压储气罐内充装的压缩空气相对于环境压力具有指定过压，最大过压可达8巴（bar）。实验所用管段可为空管（即内部为环境条件下的空气），或装填指定质量的细小颗粒。本次实验采用内径为4厘米的管段，管长分别为20、30与80厘米；同时设置了两种不同容积的高压储气罐，对应充装的高压气体容积约650立方厘米与1550立方厘米。实验过程中，在管道排气口处安装了压力传感器，用于记录实验期间的压力变化。高速相机以30000帧每秒（fps）的帧率采集实验图像。 当膜片脉冲阀开启时，会产生射流，伴随冲击波与声波在大气中传播，这些流动现象可通过高速纹影阴影摄影技术清晰显现。