Influence of foam initial liquid fraction on the effectiveness of spherical explosion attenuation in a pipe

Interaction features of a spherical shock wave formed in the center of a non-deformable pipe filled with gas and contained the protective layer of aqueous foam on its inner surface are investigated. Numerical modeling is carried out on the basis of a two-phase gas-liquid model with a single pressure of phases, taking into account interphase forces and heat transfer. Reliability of the model is confirmed by comparing the calculations with experiments on a spherical explosion in aqueous foam. Pressure evolution on the pipe surface in the near zone of shock wave initiation is analyzed in detail in the absence and presence of foams with different liquid fraction. Significant decrease in the amplitude and velocity of the wave pulse is shown by using foam protection on the pipe wall.