向心径向导叶内部流场的多工况PIV测量  

PIV measurements of inner flow field in an inward radial diffuser under multi-conditions

作　　者：黄萍[1] 张丽 周岭[1] 付燕霞[1] 陆伟刚[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 [2]格兰富水泵(无锡)有限公司,江苏无锡214112

出　　处：《排灌机械工程学报》2014年第8期674-678,共5页Journal of Drainage and Irrigation Machinery Engineering

基　　金：国家自然科学基金资助项目(51279069);江苏省普通高校研究生科研创新计划资助项目(CXLX11_0577;CXLX11_0566)

摘　　要：为了掌握导叶内部的真实流动形态,完善导叶水力设计方法,设计了一个独特的PIV试验台,对向心径向导叶内部流场进行了PIV试验测量.试验泵段取自多级深井离心泵的一级,通过2个高强度水润滑轴承支撑起整个泵轴,借助45°安放的镜面对流场图像进行折射.通过相平均方法获得了不同工况下导叶中截面的速度场分布.结果表明:在设计流量附近,导叶内部流动较为稳定规整;在大流量下,由于导叶进口过流面积有限,液体流动受阻,产生了较大的冲击损失;在小流量下,流道内产生了流动分离和旋涡,旋涡的强度随着流量的减小而逐渐加强,而且涡核的位置也由靠近导叶叶片吸力面逐渐向导叶流道中部移动;导叶进口处产生较大的水力损失,导叶进口安放角对泵性能影响较大;为改善小流量工况下的流场,导叶流道中部的过流面积需要进一步调整.In order to understand the flow pattern of the diffuser internal flow field and improve the dif- fuser hydraulic design method, a special test rig was designed and installed to investigate the flow fields in an inward radial diffuser by using the particle image velocimetry （PIV） technique. The test model is one stage of a deep-well multistage centrifugal pump, two water lubricated plain bearings were used to support the pump shaft, and a mirror placed in 45° was used to reflect the flow field of diffuser. The velocity flow fields under a variety of operational points were obtained by using the phase averaged method. The results show that the flow in the diffuser is uniform and stable at the design flow rate. At the larger flow rates, the flow is blocked by the finite throat area and a considerable shock loss is generated at the diffuser inlet. At the lower flow rates, flow separation and vortices appear, and the vortex intensity is strengthened with reducing flow rate. Meanwhile, the position of vortex core is moving from the location nearby diffuser suction side to the middle of diffuser. Large hydraulic losses produce at the diffuser inlet, and the diffuser inlet setting angle have a significant effect on the pump performance. The flow area in the middle of diffuser passage needs to be further adjusted to improve the flow pattern under lower flow conditions.

关 键 词：导叶 深井离心泵 试验 粒子图像测速 流场 

分 类 号：S277.9[农业科学—农业水土工程] TH311[农业科学—农业工程]