Numerical study on the interaction between a shock wave and porous foam and the mitigation mechanism of porous foam filling a straight tube on a blast wave

This study validated a two-phase compressible flow model considering elasto-plastic porous foams. The numerical data were compared with the previous experimental results in terms of the interaction between the planar shock wave and the porous foams and the mitigation effect of a porous foam filling a straight tube on a blast wave. The porous foams in the shock tube interacted with a planar shock wave. The drag between the shocked air and the foams reduced the shock wave strength. Moreover, the flexible foam was significantly deformed by the shock wave. The validation results confirmed good agreement and consistency between the numerical and experimental data. The mitigation effect on the blast wave caused by a high explosive, where the main parameter for comparison was the location of a rigid porous foam layer inside the straight tube, was investigated. In the first case, the porous foam plate was placed on the floor, whereas in the second case, the porous foam plates were placed on the floor, sidewalls and ceiling. The total energy transferred between the porous foam and the shocked air was computed to quantitatively understand the mitigation mechanism of the porous foam on the blast wave. The heat transfer was a dominant factor for the energy transfer from the shocked air to the porous foams. The second case further mitigated the blast wave outside, and the increment of the interface area of the air/porous foam greatly affected the blast wave mitigation.