Combustion of hydrogen-oxygen microfoam on the water base

On the basis of experimental study the paper analyzes the process of combustion wave propagation in the hydrogen-oxygen microfoam on the water base. Combustible microfoam consists of gaseous bubbles dispersed in the water solution of surfactant. Bubbles contain hydrogen and oxygen and their diameters are in the range from 60 to 230 μm. Expansion ratio of the combustible foam is in the range from 8 to 22. The paper establishes the influence of surfactant concentration, glycerol concentration, tube diameter and Shchelkin's spiral on the speed of flame propagation in the foam. It is shown that for considered range of regime parameters the characteristic mode of flame propagation in the semi-opened tube is the accelerated mode. The increase in glycerol content leads to the increase in flame speed. However after certain critical concentration of glycerol the foam loses the ability to burn. Total burning rate depends on surfactant concentration non-monotonically with characteristic maximum. Shchelkin's spiral installed at inner surface of the tube as well as the decrease in tube diameter favor flame deceleration.