Experimentally investigating pulsations of a two-phase flow in a narrow microchannel

Today, there is a revolutionary development of microchannel systems. In such systems, it is extremely important to determine the two-phase flow regime, depending on the gas and liquid flow rates. The two-phase flow in the microchannel is affected by many factors, such as the parameters of the initial section, the geometry and dimensions of the channel, the properties of the channel surfaces and liquid. In the present study, we have investigated a two-phase flow in a microchannel with a height of 50 μm and a width of 20 mm. It is shown that, with an increase in the size of the liquid nozzle, the film regimes are replaced by pulsating ones in the investigated range of gas and liquid flow rates. The characteristic frequencies of pulsations, their duration and delays are studied, depending on the superficial velocities of the gas and liquid. It is shown that the duration of the pulsation is mainly influenced by the gas flow rate, and the delay between them – by the liquid flow rate.