Abstract
The purpose of the present study is to clarify both the surface tension and the pipe diameter effects on two-phase flows in horizontal small diameter pipes. In the experiments, four-kinds of test liquids with different fluid properties were used together with 3, 5 and 9 mm i.d. test pipes. The flow parameters studied were flow pattern, bubble size, liquid film thickness, void fraction and pressure drop, etc. The flow patterns covered were bubbly, slug, and annular flows. From the measured data, the data of interfacial friction force per unit volume, Fi, was also obtained. By comparing data obtained in different pipe and test liquid combinations, the effects of the surface tension and the pipe diameter on the flow parameters have been clarified. In addition, new correlations of mean liquid film thickness and interfacial friction factor in annular flow have been derived with some dimensionless groups.
