ENDGAME - Laboratory Experiment 2024-01-18 Exp. 016 - 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.

本数据集围绕激波管（Shock-tube）实验展开，并结合高速纹影阴影摄影（Schlieren shadow photography）技术开展同步观测。
激波管实验装置由高压储气罐与圆柱形实验管通过膜片脉冲阀连接而成，该阀可将高压气体快速释放至常压实验管内。高压储气罐内填充的压缩空气相对于环境压力具备设定过压，最高可达8巴。实验管可设置为空管（内部为环境条件下的空气），或装填定量的细小颗粒。本次实验采用内径为4厘米、长度分别为20、30和80厘米的实验管，同时使用了两种不同容积的高压储气腔（约650立方厘米与约1550立方厘米）。在管路出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帧每秒的帧率采集实验图像。
当脉冲阀开启时，会产生射流，伴随冲击波与声波在大气中传播，相关流场现象可通过高速纹影阴影摄影技术清晰呈现。