浓相气力输送分支管道分流特性的数值模拟

Numerical Simulation on Dense Phase Pneumatic Conveying Diversion Characteristics in Branch Pipeline

基于Fluent软件,采用Euler-Euler两相流研究方法和RNG k-ε湍流模型及SIMPLE压力速度耦合计算方法,充分考虑颗粒间碰撞和气固两相相互作用,对3种不同几何结构的分支管内,颗粒体积分数为10%的浓相气力输送过程进行数值模拟。模拟结果显示:气固两相的速度和动压在流经分支处后都减小,且在分支处都呈现出分支内侧比外侧大的现象;分支处固相在分支内侧聚集较多;管道初始部分和分支外侧气固两相出现较大的湍流;同时随着其中一分支管与主管夹角的增大,该分支内侧两相速度、动压值和固相含量都逐渐增大,外侧湍流逐渐增强、范围逐渐变广。

Taking the collision among particles and the interaction between fluid and particles into account,the dense phase pneumatic conveying diversion characteristics of three branch-pipes with different geometric structures were analyzed based on the Euler-Euler method and the RNG k-ε turbulence model and SIMPLE pressure-velocity coupling calculation.The volume fraction of particles was up to 10% in the numerical simulation.Simulation results show that the velocity and dynamic pressure of the two phases decrease after the flow has been distributed into two branches,and the values on the inside of each branch are larger than that on the outside.The solid phase densely distributes on the inside of each branch and the turbulence is obvious in the initial section and on the outside of each branch.At the same time,with the increase of the angle between one of branches and the main pipeline,the velocities,pressure and the content of solid phase all increase on the inside of end breach,and the turbulence on the outside of each breach enhances and broadens gradually.