螺旋流中气液相界面重构、发展及演变机理

Flow patterns of gas and liquid phase can be modulated by swirl flow, leading to greatly reduced flow resistance and cost. The application of this flow has a good future in industry, such as exploitation and transportation of oil and gas, sewage disposal, heat transfer enhancement. However, mechanism and effective distance of pattern modulation by swirl flow is not clear. Reconstruction, development and transition mechanisms of gas-liquid phase interface in swirl flow, which are key problems of this flow, are lack of understanding. This work will firstly experimentally study the process of phase interface in decayed swirl flow, to obtain laws of reconstruction, development and transition of gas-liquid phase interface. Then based on numerical simulation, laws of flow field and phase motion are clarified. Combined experiment with numerical simulation, the parameter to describe the decay degree of swirl is proposed, and dynamic model of decayed gas-liquid swirl flow is established. According to this theoretical model, quantitative relationship between swirl decay and phase interface movement is obtained, mechanisms for reconstruction, development and transition of gas-liquid phase interface are revealed, mechanism and effective distance of pattern modulation by swirl flow is clarified. Research results will lay a foundation for broaden the application area of decayed gas-liquid swirl flow in industry, and providing theoretical guide for the technology of gas-liquid separation, enhancement heat transfer, material transportation and so on.

基于衰减螺旋流进行气液流型调控，能显著降低流动阻力，大大节约成本，在石油天然气开采及输送、污水处理、强化换热等工业领域具有很好的应用前景。但目前缺乏螺旋流调控气液两相流型机理及作用距离的研究，对其中关键科学问题，螺旋流中气液相界面重构、发展及演变机理认识不清。本课题首先通过实验研究衰减螺旋流中相界面运动过程，获得相界面的重构、发展及演变规律；然后展开气液两相螺旋流的数值模拟研究，获得气液衰减螺旋流的流场结构及相运动规律；基于实验及模拟认识，提出适合描述气液螺旋流衰减程度的参数，建立气液衰减螺旋流动力学理论模型，获得旋流强度衰减与相界面运动的定量关系，揭示气液相界面重构、发展及演变机理，查明螺旋流调控气液两相流型机理及作用距离。研究成果为拓宽气液衰减螺旋流在工业中的应用奠定基础，为开发先进的气液分离、强化传热和物料输送等技术提供理论支撑。

基于衰减螺旋流进行气液流型调控，能显著降低流动阻力，大大节约成本，在石油天然气开采及输送、污水处理、强化换热等工业领域具有很好的应用前景。但目前缺乏螺旋流调控气液两相流型机理及作用距离的研究，对其中关键科学问题，螺旋流中气液相界面重构、发展及演变机理认识不清。本课题首先通过实验研究衰减螺旋流中相界面运动过程，获得相界面的重构、发展及演变规律；然后展开气液两相螺旋流的数值模拟研究，获得气液衰减螺旋流的流场结构及相运动规律；基于实验及模拟认识，提出适合描述气液螺旋流衰减程度的参数，建立气液衰减螺旋流动力学理论模型，获得旋流强度衰减与相界面运动的定量关系，揭示气液相界面重构、发展及演变机理，查明螺旋流调控气液两相流型机理及作用距离。研究成果为拓宽气液衰减螺旋流在工业中的应用奠定基础，为开发先进的气液分离、强化传热和物料输送等技术提供理论支撑。