place in two-phase flows in microgravity related conditions. Two different sets of experiments
were performed on ground with air/water and air/ethanol mixtures in a minichannel with an
internal diameter of 1mm. We address questions regarding the existence of a critical void
fraction for the bubble–slug transition to occur. Experimental data are compared to the drift-
flux and Suratman models predictions. We obtain results on the extension of applicability of …