ENDGAME - Laboratory Experiment 2023-06-22 Exp. 008 - 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 fluids (water or viscous fluid) or small particles. We adopted pipes with different inner diameters (3 and 4 cm) and different lengths (30 and 80 cm). Images 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.本数据集依托激波管（Shock-tube）实验与高速纹影阴影摄影（Schlieren shadow photography）技术的结合方案构建。 激波管实验装置由高压储气罐、圆柱形实验管与膜片脉冲阀（diaphragm pulse valve）构成：高压储气罐通过该阀与圆柱形实验管相连，可将高压储气罐内的压缩气体快速释放至常压实验管中。高压储气罐内填充的压缩空气相对于环境压力存在设定过压，最大过压可达8巴（bar）。实验管内部可为空（即填充环境条件下的空气），或注入设定量的流体（水或粘性流体），亦或填充小微粒。本实验采用了不同内径（3 cm与4 cm）及不同长度（30 cm与80 cm）的实验管。图像采集帧率设置为30000帧每秒（fps）。 当膜片脉冲阀开启时，将产生射流，同时伴随激波及声波在大气中传播，而高速纹影阴影摄影技术可使这些流动现象清晰呈现。