离心泵叶轮固液两相流动及泵外特性数值分

基于N-S方程和标准k-ε湍流模型,采用SIMPLEC法,对离心叶轮三维固液两相流场进行了耦合计算,得到了固相(颗粒)不同粒径、不同体积浓度不同密度以及不同流量时的固相(颗粒)浓度分布,并研究了外特性的变化规律.模拟结果表明,颗粒本身的性质密度、粒径对颗粒的分布及运动规律影响较大,密度、粒径越大的颗粒在惯性力作用下易偏向工作面;颗粒体积浓度对颗粒的分布略有影响;泵在非设计工况下运行时,相对进口液流角的变化影响了颗粒在叶轮内的分布情况;颗粒密度、粒径、固相体积浓度的增大会引起扬程的减小.

Simulation of Solid-liquid Two-phase Turbulent Flow in Impeller Channel and Pump Characteristics Analysis

In order to study solid-liquid 3-D two-phase turbulent flow in a pump, the SIMPLEC algorithm was used with the casing to calculate the coupling question of a centrifugal impeller based on N-S equations and the standard two equations k-ε turbulent model.From the computed information, the distribution of solid particles of different particle sizes and different volume fractions, at off-design conditions and different specific gravities were obtained, and the characteristic of pump was also calculated.The results indicated that specific gravity and particle diameter, which are the nature of particles, had more influence on the distribution of solid particles.Particles with large specific gravity value and diameter were easy to trend to working face by the effect of inertia force.The volume fraction also had an effect in particle distribution; because of relative flow angle changing in off-design conditions, particles had different distribution and movement laws.Increasing specific gravity, particle size and solid-phase volume would cause the reduction of head.