Detonation in the hydrogen-oxygen microfoam on the aqueous base

Abstract

In the paper, the propagation of the detonation wave in the hydrogen-oxygen microfoam on the aqueous base is considered. Microfoam represents a two-phase system containing micron-sized gas bubbles filled with the hydrogen-oxygen mixture. These bubbles are dispersed in the water solution of surfactant (sodium dodecyl sulfate). The dependencies of detonation speed on the equivalence ratio and on the water content in the foam are obtained with the use of high-speed filming. It is found that the detonation speed slightly increases with the decrease in water content in the foam. Based on the pressure measurements, it is established that the detonation propagation in the foam is driven by relatively weak shock waves, which by themselves are not able to induce ignition of the hydrogen-oxygen mixture. To substantiate the fact of detonation existence in the microfoam a hypothesis of the cumulative collapse of gas bubbles under the shock wave action is proposed. The estimation for detonation speed in microfoam is analytically derived on the basis of simple phenomenological representations.