Modelling the dynamics of shock pulse in the tube with inner layer of aqueous foam

The dynamics of the spherical shock wave initiated by an explosion in the center of the tube containing gas and layer of aqueous foam with the volumetric liquid fraction 0,2, located near the inner tube boundary, is studied numerically. The system of model equations of aqueous foam includes the laws of conservation of mass, momentum, energy of each phase and the equation for the dynamics of foam liquid fraction in a single-pressure, two-velocity, two-temperature approximations in a three-dimensional formulation and takes into account the interfacial drag forces and contact heat transfer. The thermodynamic properties of air and water are described by the realistic equations of state. The numerical solution of the problem is realized using the free software OpenFOAM. The reliability of calculations by the proposed model is confirmed by their agreement with literary experimental data. To assess the effectiveness of foam protection, the similar problem was solved about the spherical shock wave propagation in air in the absence of the foam layer. It is shown that the presence of the foam barrier reduces the velocity and amplitude of the shock wave, protecting the tube walls from the explosion impact.