后掠式双叶片污水泵固液两相流动规律的数值模拟  

Numerical simulation of solid-liquid two-phase turbulent flow of swept-back double blades sewage pump

作　　者：程成[1] 施卫东[1] 张德胜[1] 曹卫东[1] 邢津[1] 

机构地区：[1]江苏大学国家水泵及系统工程技术研究中心,江苏镇江212013

出　　处：《排灌机械工程学报》2015年第2期116-122,共7页Journal of Drainage and Irrigation Machinery Engineering

基　　金："十二五"国家科技支撑计划项目(2011BAF14B01);江苏省产学研项目(BY2013065-03);江苏省"PAPD"项目;"333工程"项目

摘　　要：基于Particle模型,采用SIMPLEC算法、多重参考坐标系法对后掠式双叶片污水泵固液两相流场进行数值模拟.液相采用标准k-ε双方程湍流模型,固体颗粒采用离散相零方程模型,分析了固相颗粒体积浓度分别为5%,10%,15%,20%,颗粒粒径分别为0.2,0.4,0.6,0.8,1.0 mm时,固相颗粒在泵内的分布情况及其滑移速度的大小,从而进一步研究泵内过流部件的磨损情况,并探讨了颗粒浓度及大小对泵水力性能的影响规律.结果表明,颗粒直径一定时,随固相体积浓度的增大,颗粒运动轨迹偏向叶片吸力面;叶片压力面及吸力面尾部的后盖板处固体颗粒滑移速度增加明显,该处壁面产生磨损,因此设计时后盖板处应加厚;固体颗粒的粒径及固相体积浓度对泵水力外特性有着不同程度的影响,粒径增加,泵扬程、效率均下降;固相体积浓度增加,泵扬程增加、效率下降.样机试验表明:额定工况下效率为80%,扬程为11 m,设计合理,达到国内污水泵设计的领先水平.Three-dimensional simulation was performed for the solid- liquid turbulent flow in sweptback double blades sewage pump with Particle model and SIMPLEC algorithm using ANSYS- CFX software. The coupling of impeller and volute is established using multiple reference frame. The k- εdouble turbulence model was applied to predict the liquid-phase,and an algebraic named the dispersed phase zero equation was adopted to predict the solid-phase. Under the solid volume fraction of 5%,10%,15% and 20%,the effect of five different solid particle diameters（ 0. 2,0. 4,0. 6,0. 8,1. 0mm） on the particle distribution in the pump,solid particle slip velocity,the wear and tear of flow components,and the influence law of pump hydraulic overall performance were studied. Under the solid volume fraction of 5%,10%,15%,20%. The results show that with the increase of solid volume fraction,particle trajectory is biased toward the back of suction side. Slip velocity of solid particle issignificantly increased on pressure side and back shroud near the suction side＇ s trailing edge,indicating wear of the wall is exacerbated,therefore,the shroud should be thickened in design phase. In addition,solid particle size and solid volume fraction have an influence on the pump hydraulic overall performance in different degrees： the hydraulic head and pump efficiency drops with the increase of particle side,while the hydraulic head increases and pump efficiency declines with the increase of solid volume fraction. According to the test results,the efficiency of model pump can reach 80% with 11 m head at rated condition. The design of sewage pump meets the requirements,and has reached the leading level in domestic design.

关 键 词：后掠式双叶片 污水泵 固液两相流 流动规律 磨损 

分 类 号：TH312[机械工程—机械制造及自动化]