ENDGAME - Laboratory Experiment 2024-01-16 Exp. 004 - 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.本数据集包含结合高速纹影阴影摄影（high speed Schlieren shadow photography）的激波管实验。 该激波管装置由高压储气罐与圆柱形管道通过膜片脉冲阀（diaphragm pulse valve）连接构成，该阀可将加压气体快速释放至常压管道内。高压储气罐内充装的压缩空气相对于环境压力具有设定过压，最高可达8巴。实验所用管道可空置（即内部为环境条件下的空气），或装填定量的细小颗粒。本实验采用内径为4 cm、长度分别为20 cm、30 cm与80 cm的管道，同时设置了两种不同容积的加压气体工况，分别约为650 cm³与1550 cm³。在管道排气口处安装了压力传感器，用于记录实验过程中的压力变化。高速相机以30000帧每秒的帧率采集图像。 当阀门开启时，会产生射流，伴随冲击波与声波在大气中传播，这些现象可通过高速纹影阴影摄影清晰显现。