射流自吸式离心泵三维湍流数值模拟与实验分析  

Numerical Simulation and Testing Analysis of Three Dimensional Turbulence Flow in Flow-ejecting Self-priming Centrifugal Pump

作　　者：王维军[1] 王洋[1] 李贵东[1] 印刚[1] 曹璞钰[1] 

机构地区：[1]江苏大学流体机械工程技术研究中心,镇江212013

出　　处：《农业机械学报》2014年第3期54-60,共7页Transactions of the Chinese Society for Agricultural Machinery

基　　金：“十二五”国家科技支撑计划资助项目（2011BAF14801）、江苏高校优势学科建设工程资助项目和江苏省研究生培养创新工程项目（CXLX13-662）

摘　　要：为了获取射流自吸式离心泵内部流动信息，以一内置射流喷嘴的自吸式离心泵为研究对象，建立了各过流部件三维水体，采用了RNG κ-ε湍流模型，通过6组网格无关性检查，确定了计算所需网格，运用CFX14．0流场分析软件数值模拟预测了7种不同工况下外特性和内部流动，得到了全流场压力、速度等物理量变化规律，并将数值模拟结果与开式实验台测试结果作了对比分析。结果表明，设计工况下数值模拟与实验扬程、轴功率和效率的相对误差为2．63％、6．16％和14．29％，泵实际效率较低，其值为15．68％；当流量p〈3．5m3／h时数值模拟和实验的功率曲线呈近似水平直线，变化很平缓；喷嘴到直线段之间的速度分布沿旋转轴对称，扩散段和叶轮进口之间速度呈上大下小分布，液流不均匀进入叶轮进口；L=0．148m处是静压、速度和湍动能耗散率等物理量剧烈变化的分界点，静压在此处为最小值，而速度和湍动能耗散率为最大值。数值计算结果为该泵性能预测设计提供了直观的理论依据。In order to gain the inner flow field of flow-ejecting self-priming centrifugal pump, a flow- ejecting self-priming centrifugal pump equipped with a jet in the front of impeller inlet was chosen as the study object. The geometric model including all parts was built up by Pro/E software. The turbulence model chosen was RNG κ-ε turbulence model and the mesh independence was checked by six meshes with different grid number. The external performances and the inner flow fields under seven different working conditions were simulated by CFX 14.0. The profiles, such as static pressure and velocity, were obtained. Then, the numerical results were compared with the testing results gotten on open test bed. The results show that the errors of head, shift power and efficiency between the simulation and the testing under designed condition are 2.63% , 6. 16% and 14.29% , respectively. The simulating and the testing power curves are almost horizontal lines and change slowly when the flow rate is smaller than 3.5 m3/h. The absolute velocity distribution between the nozzle and the line segment is axial symmetry. However, between the diffusion section and the impeller inlet, the upper velocity is larger than the lower velocity. And the velocity of the flow entering the impeller inlets is not uniform. The location, L = 0. 148 m, is a critical location where the static pressure is the smallest and the turbulence dissipation rate achieves its maximum value. The numerical results provide a directly theoretical guideline for the pump design.

关 键 词：射流自吸式离心泵 性能预测 数值模拟 

分 类 号：TH311[机械工程—机械制造及自动化]