ENDGAME - Laboratory Experiment 2024-01-17 Exp. 013 - 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.本数据集围绕结合高速纹影阴影摄影（Schlieren shadow photography）技术的激波管（Shock-tube）实验展开。本激波管实验装置由高压储气罐与圆柱形管段构成，二者通过膜片脉冲阀相连，该阀可将高压气体快速释放至常压管段中。高压储气罐内充装的压缩空气相对于环境压力具备设定过压，最大过压可达8巴（bar）。实验管段可分为两类：一类为空管（内部为环境条件下的空气），另一类装填有定量细小颗粒。本次实验采用的管段内径均为4厘米，长度分别为20、30和80厘米；同时设置了两种高压气体充装体积，分别约为650立方厘米与1550立方厘米。实验过程中，于管道排气口处安装压力传感器，用于记录实验期间的压力变化；高速相机的图像采集帧率为30000帧每秒（fps）。当膜片脉冲阀开启时，会产生射流，激波与声波随之在大气中传播，借助高速纹影阴影摄影技术，这些流动现象可被清晰捕捉记录。