Reviewed of Gas-Liquid Two-Phase Flow Pattern in Level and Inclined Tube

The phenomenon of two-phase flow is common in nature and production practice. Two-phase flow comprises different flow forms under different conditions, namely flow pattern, Two-phase flow pattern is an important aspect in the study of two-phase flow, and it immensely influences the pressure and characteristics on heat and mass transfer, which affects accurate measure of flow parameters and the operation of equipment simultaneously. The flow resistance of different flow patterns can vary even a few times under the same quantity. According to the representative literature, when different experiment medium property, experimental device and experimental conditions are used, the gas-liquid two-phase flow shows different flow characteristics. The complex variational phase distribution types affect the flow characteristics such as pressure drop of gas-liquid two-phase and the water holdups. Therefore, the research on flow patterns is crucial, and all countries are researching the two-phase flow pattern. We briefly explain the relevant knowledge about two-phase flow pattern. In addition, the author enumerates and analysises the domestic and international present situation of the research about the two-phase flow pattern both in level and inclined pipe, and points out the notes in the future research. Finally, the author points out that the development of flow pattern still has a long way to go, although fruitful achievements have been made.