Shock wave propagation from a shotgun shell

Shotgun shell blanks with no projectiles are used to produce shock waves which are used for seismic mapping in geologic materials. The shock wave produced by the shotgun shell is examined here to understand its propagation in air, solid PMMA, and through a granular sand material. Schlieren imaging techniques and ultra high-speed cameras are implemented to visualize the wave propagation. Quantitative tools including quantitative schlieren, Photon Doppler Velocimetry (PDV), and accelerometers are used to characterize the shock wave density and particle velocity at various distances from the source in each propagation medium. The pressure-time history in the shotgun shell case is measured and used to further understand the shock wave source. The measurement suite allows characterization of the shock wave propagation in the near and far fields which is critical for its use as a seismic mapping source.