On the initiation of bubble detonation by small-amplitude waves

The possibility of initiating detonation waves in bubbly liquids with a flammable gas phase by low-amplitude pressure waves is studied by means of numerical simulation. The cases of preliminary decrease in the initial pressure at the medium boundary before the impact of the compression pulse and the impact on the fluid boundary by two successive pressure waves, each of which individually is not capable of initiating a detonation wave, are considered. In the first case, the influence of the parameters of the preliminary unloading wave (the degree of pressure reduction, the duration of the rarefaction phase), as well as the initial concentration of bubbles on the minimum amplitude of the compression pulse capable of initiating bubble detonation in the medium, is analyzed. In the second case, the possibility of initiating detonation waves not at the boundary but inside the bubble system, is shown. It is found that, depending on the initial gas content of the medium and the amplitude of the acting waves, the propagation of a detonation wave from the ignition source can occur both in both directions (the initial and reverse direction of the initiating wave) and only in the initial direction.