颗粒参数对螺旋离心泵流场及过流部件磨损特性的影响  

Effect of particle parameters on flow field and erosion wear characteristics of flow passage components in screw centrifugal pump

作　　者：申正精 楚武利[1] 董玮[1] Shen Zhengjing;Chu Wuli;Dong Wei(School of Power and Energy,Northwestern Ploytechnical University,Xi’an 710129,China;School of Energy and Power Engineering,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]西北工业大学动力与能源学院,西安710129 [2]兰州理工大学能源与动力工程学院,兰州730050

出　　处：《农业工程学报》2018年第6期58-66,共9页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金资助项目(51236006);甘肃省青年科技基金计划(1606RJYA297)

摘　　要：为了研究颗粒参数与螺旋离心泵过流部件表面磨损特性的影响,该文结合数值计算与试验方法,分别引入Mclaury和OKA 2种磨损预测模型对螺旋离心泵内固液两相流场进行求解,并将2种模型中所包含的关联因子函数进行了推导和分析,建立了颗粒参数与过流部件表面磨损的内在关联。结果表明:所采用的数值计算模型准确性较好,相对误差在可接受范围内;叶片工作面的磨损主要集中在叶片头部和螺旋段轮缘附近,叶片背面磨损主要发生在叶轮离心段,蜗壳内壁主要磨损区域为隔舌和靠近出口断面附近;颗粒粒径在0.05~0.16 mm范围内,粒径的增加促进磨损,而当粒径大于0.16 mm后,磨损增长放缓;颗粒体积分数在3%~6%范围内,颗粒体积分数的增加会加剧磨损,而从6%增加到7%时,隔舌处磨损持续增加,在周向角度为101°~326°的截面范围内,颗粒体积分数的增加会抑制蜗壳内壁磨损;颗粒速度与磨损呈正相关,且对磨损的影响较大,不同速度下蜗壳内壁各部位的磨损率变化趋势相近。在此基础上,给出了固液两相流泵水力设计和结构设计的优化方向,该文为提高两相流泵抗磨损性能提供了参考。Sediment erosion wears are recognized as serious engineering problems in slurry handling industries.As a kind of solid-liquid two phase flow delivery pumps,screw centrifugal pump has a wide efficiency region and non-plugging performance,however,the problem of erosion wears in it can not be overlooked.In this study,the flow field of screw centrifugal pump was simulated by using the Euler-Lagrange method when the numerical results coincide well with the experimental results.The RNG(renormalization group)k-εturbulence model was used to solve fluid flow based on the grid-scale,and the DPM(discrete phase model)method was used to solve the information of particle motions under the particle-scale.The impact of particles to impeller and volute surfaces were calculated through the Tabakoff particle restitution coefficients formula.The grids of computational domain were generated by ANSYS ICEM(integrated computer engineering and manufacturing)software.Because of the complex structure of the screw centrifugal impeller,the tetrahedron and triangular prism hybrid grids which had strong adaptability were selected.And the grid project was thought to be suitable for computation after the grid independence test and verify.The interface between dynamic and static domain was set to frozen rotor,and also the wall free sliding function was used.The SIMPLE algorithm was used to couple the pressure and velocity of the computational domain,and the two order upwind scheme was used to discretize the N-S equation.The convergence precision as 10-4 was set when the total pressure of the pump outlet tends to be stable,and it was considered that the convergence standard was reached.We adopted the Mclaury and OKA models to predict the flow passage components erosion.By calculating and deriving the correlation factor functions contained in those two erosion models,it was found that the function of material hardness and impact angle almost had the same trend of change in two models.The hardness of material is negatively correlated with the erosi

关 键 词：离心泵 模型 磨损 颗粒参数 固液两相流 

分 类 号：TH311[机械工程—机械制造及自动化] O359[理学—流体力学]