Dynamics of Formation and Parameters of a Fog upon Abrupt Expansion of a Compressed Vapor–Gas Volume

This paper deals with an experimental investigation of structural changes in the compressed vapor-gas volume of a water vapor–hydrogen–air system, which are caused by an abrupt expansion of the volume due to the loss of integrity of the confinement shell. A homogeneous system transforms to a heterogeneous water vapor–microdroplets–hydrogen–air mixture behind the rarefaction wave. The microdroplet sizes and their bulk concentration are measured during the formation of a fog. A method is proposed for estimating the volume fraction of microdroplets from the measurements of light absorption on one wavelength of the IR region.