Dynamic Analysis of Shock Propagation from Shock Tube for Blast Testing

Abstract

The shock tube facility has been a subject of interest for over a century. Its applications extend to myriad of engineering studies such as high-speed aerodynamic testing, shock wave characterisation, observation of compressible flow structure, combustion reactions in gas phase, and examination of blast wave impact on biological species. In this work, an open-end shock tube facility is used to generate a moving shock wave that is useful for engineering and medical testing. Experiments are carried out to validate the flow solver, and the latter is used to visualise the flow downstream of an open-ended shock tube. It is observed that the design of the open end can affect the temporal and spatial characteristics of shock waves, which is vital for various applications. A conically diverging nozzle delays the formation of expansion fans, however, the delays is insignificant for the configuration under consideration. Increasing the radius of a round diverging nozzle causes shock wave formation at an earlier time step, with the height of the test section remaining unaffected. Nonetheless, the blast shock preceding Mach disk provides more testing time when the radius increases. These findings are crucial in understanding how shock tube geometry and other factors affect testing procedures.