叶片参数对离心泵关死点性能影响的试验分析

Experiment Analysis about Effects of Impeller Parameters on Centrifugal Pump Characteristics at Closed Valve Conditon

一直以来离心泵关死点扬程和功率都无法通过理论计算获得。以某比转数为92.7的离心泵为研究对象,试验测试了不同叶片出口角、叶片出口宽度和叶片数下关死点扬程和功率的变化规律。试验结果表明关死点扬程随着叶片出口角的增大变化较小,随着片出口宽度的增加一直增加,随着叶片数增加先减小后增大;3个参数对关死点功率的影响都比较复杂;3个参数对关死点性能的影响大小顺序为叶片出口宽度最大,叶片数次之,叶片数最小。研究结果对于现代离心泵的设计具有比较重要的参考意义。

Up to now, head and power of centrifugal pumps at closed valve condition can not be obtained by theory calculation. A centrifugal pump, whose specific speed is 92.7, is chosen as research model. The blade outlet angle, blade outlet width and blade number of impeller are changed, then the pump with differernt impellers is tested at closed valve condition. The axial velocity circulation and blade angle variety with linearity distribution are used to deisign the impeller. The experiment results indi cate that the effects of blade outlet angle on head at closed valve condition is small. With the increase of blade outlet width, the head at closed valve condition also increases. With the increase of blade number, there is a maximum for head at closed valve condition. The impacts of the three parameters on power at closed valve condition are all complicated. The blade outlet width has the most effcts on the pump characteristics at closed valve condition, while the blade outlet has the least effects. The study fruits can instruct the hydraulic design of moderm centrifugal pump with.