Influence of cylindrical shell on spatial distribution of pressure during propagation of divergent shockwave

The propagation and spatial distribution of the divergent shock wave in PMMA under the restriction of a metal cylindrical shell were studied using experiment and numerical simulation. The flyer was driven by the cylinder high explosive initiated by a detonator at the center of the free surface and the inner pressure of PMMA was measured by PVDF. The experiment shows that the closer to the axis at a unique spot, the smaller the first pressure amplitude, which is the result of the increased impacted area of PMMA by the forward convex-shaped flyer due to the divergent shock wave and the increased integrative and accumulative effect of the pressure beyond the axis. But during the subsequent propagation of the shock wave, the closer to the axis, the smaller the pressure amplitude, which is the result of the interaction between the shock wave front and the reflection of the divergent shock wave from the cylindrical shell. The numerical simulation was performed well by adjusting the severe distortion of the mesh which may cause the termination of the calculation. The trend of the numerical result is in qualitative agreement with that of the experiment. Finally, we discussed the effect of different shell materials on the law of the distribution of the shock wave, and it is shown that the subsequent pressure increases as the heavy density of the cylindrical shell increases.