摘要
为了研究中比转速离心泵性能及内部流场特性,以比转数102离心泵为研究对象,采用fluent,在双参考坐标系下,选用RNGk-ε模型,应用有限体积法对雷诺时均N-S方程离散计算,压力和耦合采用SIMPLEC算法求解。同时,为了提高预测精度,采用5套不同网格方案对模型泵的效率进行网格无关性检验。并且从小流量工况下计算结果分析对比,得到离心泵外特性及内部流场变化规律。研究表明:数值计算与实验结果相比,设计工况下,扬程的预测误差为2.02%,效率的预测误差为1.99%;随着流量的降低,计算效率的误差逐渐增大。在设计点,离心泵的内部速度流线比较光顺;而在小流量工况下,离心泵进口和叶轮均出现漩涡现象;随着流量的降低,漩涡面积增大,数量也在增加。
In order to explore the internal flow characteristics of the medium specific speed pump, this paper takes the centrifugal pump with special speed of 102 as the research object, uses fluent software and standard k-ε model in the two-reference coordinate system to conduct discrete calculation based on time-average Renoyld N-S equations with the finite volume method. Pressure and cou- pling are calculated with SIMPLEC algorithm. Meanwhile, to improve the accuracy of prediction, 5 different numbers of grids are used to test for the grid independence of the efficiency of the model pump. External characteristics and internal flow field change rule of the centrifugal pump at a small flow rate are concluded by means of analysis and contrast of the calculation results. The research shows that compared with experimental results, in the numerical calculation, the prediction errors of lift and efficiency are 2. 02% and 1.99% respectively. With decreasing flow, the computational error of efficiency increases. At the design points, the internal speed flow lines of the centrifugal pump are relatively smooth, while under low flow rate conditions, vortexes occur at inlets and impeller of the centrifugal pump. With decreasing flow, both area and number of the vortexes increase.
出处
《中国农村水利水电》
北大核心
2016年第7期99-102,106,共5页
China Rural Water and Hydropower
基金
国家自然科学基金项目(51309034)
关键词
中比转速离心泵
内部流动
无关性
误差
数值模拟
medium specific speed pump
internal flow
independence
error
numerical simulation
