垂直管道内层流泡状流运动的多流体模型

常用的描述泡状流运动的双流体模型采用一个平均尺寸对气相进行描述。不同尺寸气泡的运动和受力不同。当气泡尺寸分布范围较大时 ,不宜采用双流体模型描述泡状流。根据气泡的尺寸划分气相 ,采用时间平均法建立了描述垂直管道内层流泡状流运动的多流体模型。通过对气泡在流场中的运动和受力分析 ,给出了用以封闭模型的粘性应力、脉动应力、相间动量交换项的表达式。利用模型对具体实验进行了预测 ,模型预测值与实验值的比较结果表明采用多流体模型能够预测气泡尺寸范围较大的泡状流

Multi-fluid model for laminar bubbly flow in a vertical pipe

Different size bubbles have different dynamic and kinetic behaviors. The commonly used two fluid models are not suitable for bubbly flow with non uniform bubble sizes. A more detailed multi fluid model was developed with the gas phase divided into several groups according to bubble size to describe bubbly flow in a vertical pipe. Analysis of bubble motion in the flow field was used to develop relations for the viscous stresses, turbulent stresses, and interfacial momentum exchange to close the model. Experimental data was used to check the model. Comparison between predicted values and experimental data shows that the model accuratcly describes laminar bubbly flow with non uniform bubble sizes.