多级泵首级叶轮瞬时启动特性数值研究Numerical Study on Transient Startup Characteristics of the First Stage Impeller of a Multistage Pump
张玉良,赵燕娟,汪灿飞,蔡海兵
ZHANG Yu-liang,ZHAO Yan-juan,WANG Can-fei,CAI Hai-bing
摘要(Abstract):
多级离心泵应用普遍且结构复杂,是必不可少的重要流体输送设备。目前对其已有研究几乎全部集中在稳定工况点下开展的,而对其在突然启动瞬态过程中的特性研究却非常少。以一台中比转速多级离心泵为例,基于滑移网格技术和用户自定义函数功能,对该模型泵转速快速上升过程中首级叶轮的内部非定常流动进行了数值计算。结果显示:叶轮进口处的湍动能和湍流强度呈现先降后升再降的变化趋势,而叶轮出口处的湍动能和湍流强度呈现先降后升的变化特征;启动初始时刻,叶轮功率缓慢上升,而后随转速快速上升;无量纲扬程在启动初始时刻具有极大值,随后快速下降至最小值,紧接着又缓慢上升至稳定值。
Multistage centrifugal pumps are widely used and their structure is complex,it is an important equipment requisite for transmitting various kinds of fluid media. Up to now,almost all studies on multistage centrifugal pumps focus on the stable operating conditions,whereas there are very few investigations on their characteristics upon instantaneous startup. So,in this paper,a multistage centrifugal pump with middle specific speed was employed as the research object to numerically calculate the internal unsteady viscous flow during rapid startup based on the sliding mesh technique and the user defined function(UDF). The results show that the turbulent kinetic energy and the turbulence intensity at inlet of impeller first rise,then decrease,and finally rise again,whereas both of them at outlet of impeller first decrease and then rise.At the beginning of startup,the impeller power slowly rises,and then rises rapidly with the rotating speed. The non-dimensional instantaneous head is very high at the very beginning of the startup,and quickly falls below the quasi-steady value,then gradually rises to the stable quasi-steady value.
关键词(KeyWords):
多级离心泵;快速启动;首级叶轮;非定常流动
multistage centrifugal pump;rapid startup;first stage impeller;unsteady flow
基金项目(Foundation): 国家自然科学基金重点基金项目(51536008);; 浙江省自然科学基金项目(LY18E090007);; 机械工程浙江省重中之重学科和浙江理工大学重点实验室开放基金项目(ZSTUME01A05);; 衢州学院中青年学术骨干项目(XNZQN201508)
作者(Author):
张玉良,赵燕娟,汪灿飞,蔡海兵
ZHANG Yu-liang,ZHAO Yan-juan,WANG Can-fei,CAI Hai-bing
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