2017 年 31 巻 3 号 p. 257-266
In this article, our experimental studies on the characteristics of adiabatic two-phase flows in microchannels have been reviewed. In these experiments, horizontal circular capillary tubes of 75-250 μm I.D. and a square channel with hydraulic diameter of 250 μm were used as the test channel to study the effects of the tube diameter and the channel shape on the characteristics. In order to clarify the effects of liquid properties, Newtonian liquids as well as non-Newtonian ones were used as the test liquid, while nitrogen gas as the test gas. Furthermore, the effects of gas-liquid inlet and mixing conditions have been studied by adopting several mixing methods. The significant effects have been seen on two-phase flow characteristics, i.e., two-phase flow pattern, void fraction, bubble velocity, bubble length and pressure drop, in microchannels. Also, characteristics of the two-phase flow through singularities such as bend, contraction and expansion in microchannel are addressed.
