气—幂律两相流体流经截面突缩管的数值模拟

Numerical simulation on two-phase flow of air and power-law liquid through suddenly shrunken channels

张军 郑捷庆

ZHANG Jun ZHENG Jie-qing

集美大学机械工程学院, 福建厦门 361021

School of Mechanical Engineering, Jimei University, Xiamen 361021, Fujian, China

为揭示空气-幂律流体流经截面突变时的两相流动规律,尤其是两相参数沿流向及管截面分布及压降的变化规律,根据气液两相流理论,并考虑幂律流体的本构方程,建立了空气-幂律流体两相流动数学模型。在此基础上,采用商业软件Fluent对空气-幂律两相混合物流经截面突缩管道的流动特性进行了数值模拟,获得了两相参数沿轴向及截面方向的分布规律。研究表明:气相、液相速度及压降随着输入含气量的增大而增大;两相参数在截面突变附近有急剧的改变,但其突变位置却有所不同;另外,两相参数的截面分布沿流程也有所不同。这些研究结果对相关系统的设计提供了理论依据。

A mathematical model of two-phase air and power-law flow is developed on the basis of the two-phase flow theory of gas and liquid and the constitutive equation of power-law fluid.The flow characteristics of two-phase mixtures of air and power-law fluid through a suddenly shrunken channel are numerically simulated by using commercial software named Fluent.Then the distribution law of two-phase parameters along axial and sectional directions is obtained.Research results show that the higher the gas velocity,liquid velocity,and pressure drop are,the more the input gas content increases.What’s more,the two-phase parameters change abruptly nearby the suddenly shrunken section,yet the mutation positions are different.In addition,the sectional distribution of the two-phase parameters is also different along axial direction.All the research results provide a theoretical basis for the design of relevant systems.

10.3969/j.issn.1000-7393.2007.03.034