The Modes of the Upwardflow of Air-Water Mixtures in a Vertical Tube

Abstract

Though the flow modes of two-phase fluid are important in many problems such as the heat transfer and the pressure drop, there are few studies on those of upwardflow in a vertical tube. This paper mainly deals with the following experimental works : (1) Constitution diagram of flow mode regions. (2) Mechanism of transition from bubble flow to seperated flow. As the results of experiment it has become clear that the constitution diagram based on the flow rates of air and water is influenced by the diameter of pipe. Then the author proposes the new diagram which has no connection with the diameter. The above mechanism has been made clear as the stability problem of bubble motions.