以空气和水为工质,对摇摆状态下管径为25mm有机玻璃管内两相流流型转换规律进行了实验和理论研究.依据稳态条件下的流型转换机理,通过考虑摇摆引起的附加惯性力的作用,确定了影响分散泡状流和环状流型转换的主要因素,进而提出摇摆状态下分散泡状流向泡状流或间歇流和环状流向分层流+间歇流或间歇流型转换的准则关系式.并将该理论模型与实验数据以及稳态条件下的半理论公式进行了比较,结果表明新准则关系式要比稳态关系式能更好地预测摇摆状态下流型转换边界.
A series of experiments on single-phase and two-phase flow were conducted in a 25mm diametered horizontal pipe that was being rolled. The test section was transparent glass pipe with air and water used as working fluids. The study was designed to investigate the effects of rolling motion on the motion of gas bubbles, dispersed bubble flow and liquid film thicknesses for annular flow. By considering the addi tional inertia force on flow behavior, the major factors that affected the transition between dispersed bubble and annular bubble were determined. Furthermore we put forward a transition criterion in rolling state where the dispersed bubble flow was transformed into bubble flow or intermittent flow; or the annular flow was changed into intermittent flow or intermittent plus-stratified flow. Comparison was made by using the experimental data, the proposed theoretical model and the half-theoretical expression in stable condition, showing that the model proposed in this paper can better predict the flow-pattern transition boundary in rolling state than the half-theoretical expression in stable condition.