Wave processes in a vapor-liquid medium, caused by the expansion of vapor cavity

The wave processes in a vapor-liquid medium, which arise upon injection of vapor into the flow and expansion of the vapor cavity, are studied experimentally in a Freon stand. The experiments are performed with an upward flow of R318C Freon in adiabatic and heated channels. An integrated study is made of the thermogasdynamic process in a vapor-generating channel, caused by the expansion of the vapor cavity; the study involves multipoint measurements of the dynamics of pressure field and void fraction and of the wall and flow temperature, as well as high-speed video filming of the process. The propagation of pressure wave is accompanied by the formation of a high-velocity liquid plug and wave steaming of the channel. It is demonstrated that, in the case of a vapor-generating channel with local drag, the abnormally high pressure in reflected wave is associated with hydraulic shock upon deceleration of the liquid plug. Gasdynamic analysis of the process is performed, and the calculation results are compared with the experimental data.