Visualization of underwater explosion of spherical explosives

The behavior of underwater shock waves generated by underwater explosion of high explosives have been investigated for many years. On spherical explosives, the behavior of underwater shock waves have also been investigated by many researchers, and the strength of the underwater shock wave far from the origin of the explosives have been known. However, there have not been the information concerning the strength or the attenuation process of the underwater shock wave close to the origin of the explosives, Therefore, the underwater shock wave close to the spherical explosives was observed by optical measurements. The results obtained by the optical measurements were compared with the results obtained by numerical calculation and pressure measurement. An arbitrary Lagrangian-Eulerian (ALE) method was used in our basic calculations, Tourmaline gauges were used in pressure measurement. The usual shadowgraph system was used to take both framing and streak photographs with an image converter camera It concludes that the strength of the underwater shock wave decreases exponentially with the increase of distance from original explosives, and its inclination of the line was about -2.5 in the case of the spherical SEP and was about -1.8 in the case of the spherical PBX.