摘要
为定量研究肘形进水流道对轴流泵水力性能的影响，实现性能预测，该文采用雷诺时均N-S方程和标准紊流模型，数值模拟了某肘形进水流道和轴流泵联合运行时的三维流场，获得了水泵的流量～扬程曲线、流量～功率曲线和流量～效率曲线，并与设计进水条件下的水泵性能进行了对比。在该肘形进水流道提供的进水条件下，在计算流量范围内，泵的扬程和效率分别平均下降约8．62％和5．74％，轴功率平均增加约3．56％，最优工况点效率降低了5．99％，流量减少了8．59％。通过5个肘形进水流道设计方案的计算对比发现，流道出口水流的偏流角与水泵性能的发挥密切相关，在相同流量下，水泵效率差值达4．34％。因此，为确保水泵高效、安全地运行，应重视进水流道水力设计优化和面向对象的水泵设计，改善水泵进水条件，减少进水流道对水泵水力性能的影响。
In order to investigate quantitatively the influence of elbow inlet passages on the hydraulic characteristics of axial-flow pumps and achieve performance prediction, the time-averaged Navier-Stokes equations and standard turbulence model were adopted to simulate the three-dimensional flow field of an elbow inlet passage with an axial-flow pump. The characteristic curves of discharge vs. head, power and efficiency of the pump were obtained and compared with those obtained under standard flow conditions. Within the range of computed discharges and under the flow conditions supplied by the elbow inlet passage, the head and efficiency of the pump dropped averagely by 8.62% and 5.74%, respectively, while the shaft power approximately increased by 3.56%. The efficiency at the best efficiency point （EFP） dropped by 5.99% and the corresponding discharge decreased by 8.59%. Through computation and comparison of five design schemes of elbow inlet passage, it is found that swirl angles at the outlet section of elbow inlet passage correlate closely with pump performance and the maximum difference of the pump efficiency can be as high as 4.34 % at a certain discharge. Hence, for the purpose of guaranteeing high efficiency and safety operation of pump, more attentions should be paid to the optimization of hydraulic design of inlet passages and object-oriented design of pump to improve flow conditions of pump and reduce effect of intet passage on pump hydraulic performance.
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2006年第2期6-9,共4页
Transactions of the Chinese Society of Agricultural Engineering
基金
十五攻关项目(ZZ02-03-01-04/05-01)
水利部科技创新项目(SCX2003-12)
江苏高校省级重点实验室开放课题(KJS03087)
江苏省教育厅指导性计划项目(LK0410185)
关键词
肘形进水流道
数值模拟
水力性能
立式轴流泵
性能预测
numerical simulation
elbow inlet passages
hydraulic characteristics
vertical axial-flow pumps
performance prediction
