摘要
为研究叶片包角对高比转速离心泵固液两相流动的影响,采用Mixture多相流模型,利用CFX软件对5种不同叶片包角的高比转速离心泵进行了固液两相湍流数值模拟,分析了固液两相流中固体体积分数分布及速度变化规律。研究表明:在2%的泥沙含量条件下,随着叶片包角的增加,效率有所下降,叶片包角φ=100°时效率最优;颗粒主要分布在叶轮后盖板及叶片背面尾部;固体速度在距后盖板的0.7位置及叶片头部位置达到最大;随着包角的增大,叶轮流道内的压力在减小,后盖板、叶片背面尾部的颗粒浓度明显降低,流道和叶片上的固体速度会增加;颗粒浓度下降速度快慢的临界点在距离后盖板0.15处;叶片背面颗粒浓度的峰值点出现在叶片长度为0.9处,此时,φ=110°时的颗粒含量受到包角的影响最大;综合颗粒体积分数及固相速度的分布规律,适当增大叶片包角使得效率降低,但可改善固液两相流离心泵后盖板及叶片背面磨损情况。
In order to explore the effect of blade packet angle on the solid-liquid two-phase flow of centrifugal pump with high specific rotational speed,this paper uses the mixture multiphase flow model and CFX to simulate the solid-liquid two-phase turbulence for high-ratio rotational speed centrifugal pumps with different blade packet angle,and analyzes the distribution law and velocity variation of solids in the solid-liquid.The results show that under the condition of 2%sediment content,the efficiency decreases with the increase of blade packet angle,and the optimal efficiency is reached as the blade packet angleφ=100°.The particles are mainly distributed in the rear cover plate of the impeller and the tail of the back of the blade,and the solid velocity reaches the maximum at 0.7 position and blade head at the rear cover plate.With the increase of the packet angle,the pressure in the blade rotation channel decreases,the concentration of particles in the rear cover plate and the back of the blade is clearly reduced,and the solid velocity on the runner and blade increases.The transition point of the decreasing rate of particle concentration is located at 0.15 from the rear cover plate,and the peak point of the particle concentration on the back of the blade appears at the blade length of 0.9,meanwhile,the effect of blade packet angle on the particle content is the most atφ=110°.By considering the distribution law of particle volume fraction and solid phase velocity,increasing the blade packet angle decreases the efficiency,but it can improve the wear of the rear cover plate and blade back of the solid-liquid two-phase flow centrifugal pump.
作者
万丽佳
宋文武
常方圆
张明祯
WAN Li-jia;SONG Wen-wu;CHANG Fang-yuan;ZHANG Ming-zhen(School of Energy and Power Engineering,Xihua University,Chengdu,Sichuan,China,610039)
出处
《热能动力工程》
CAS
CSCD
北大核心
2020年第2期78-86,共9页
Journal of Engineering for Thermal Energy and Power
基金
四川省科技厅项目(2016JY0187)
四川省教育厅重大培育项目(14CZ0013)。
关键词
离心泵
固液两相
叶片包角
固体速度分布
固体体积分数分布
centrifugal pump
solid-liquid two-phase
blade packet angle
solid velocity distribution
solid volume fraction distribution
作者简介
万丽佳(1994-),女,四川自贡人,西华大学硕士研究生,E-mail:1142237415@qq.com.
