A research of damping properties of aqueous foam uder the impact of spherical shock waves

Background. The study is aimed at analyzing the behavior of aqueous foam under the conditions of explosive impact in order to improve its damping properties. For this purpose the authors have constructed a mathematical model that takes into account the foam's structural features, its computer realization and comparison of obtained solutions with new experimental data, which is a very relevant and important scientific direction. Materials and methods. The authors have developed a two-phase behavioral model of aqueous foam under strong spherical shock wave impact, described by equations of momentum conservation for mixture, mass and internal energy of each phase in Lagrangian variables, taking into account bulk viscosity and interphase heat exchange. The numerical realization of the model was carried out by the counting method, using the Neumann-Richtmayer viscosity and the Courant stability condition. A spherical explosion was modeled in the form of a shock wave, which has the energy of explosive charges used in experiments. Results. The authors have achieved a satisfactory agreement between the numerical solutions and new experimental data on spherical explosions in gas and aqueous foam. The causes leading to a significant decrease in amplitude and shock wave velocity in the studied media have been investigated in detail. Conclusions. As a result of the numerical study using the proposed model of aqueous foam, taking into account interfacial contact heat exchange and viscosity, it has been established that shock compression of the foam leads to its compaction, greatly reduces the amplitude and propagation velocity of shock waves and, consequently, is accompanied by a considerable dissipation of explosion energy in comparison with the gas medium.