摘要
为了探索叶片包角在固液两相流下对低比转速离心泵非定常特性的影响,利用ANSYS CFX软件采用Mixture多相流模型对4种不同叶片包角离心泵的固液两相湍流进行了非定常数值模拟,分析了叶片包角对离心泵瞬时扬程、压力及压力脉动的影响。研究表明:随着叶片包角的增大,瞬时扬程会降低,并且降低速度越来越快;叶片包角每增大10°,瞬时扬程的波动时间延迟0. 000 52 s。随着叶片包角的增大,叶片工作面与叶片背面的压力会降低。叶片包角每增加10°,固液两相流时离心泵的压力脉动时间均向后延迟0. 007 s。不同包角下的主要脉动幅值均出现在转频处。颗粒浓度为0. 02和0. 05时,压力脉动最小值均出现在叶片包角值为140°时;当颗粒浓度为0. 1时,脉动幅值随着叶片包角的增大而减小,叶片包角从130°增加到160°时,此时的压力脉动受到叶片包角的影响最为严重,脉动幅值减小了14. 52%。因此,在高颗粒浓度下适当增加叶片包角可以改善固液两相离心泵的压力脉动。
In order to explore the effect of blade packet angle on the unsteady characteristics of centrifugal pump with low ratio speed in solid-liquid two-phase flow,this paper uses ANSYS CFX software to simulate the solid-liquid two-phase turbulent flow with 4 different blade packet angles by using the mixture multiphase stream model,and analyzes the effects on the instantaneous head of the centrifugal pump,and on the pressure and pressure pulsation. The results show that with the increase of the blade packet angle,the instantaneous head decreases and the speed decreases more and faster,and the fluctuation time of the instantaneous head is delayed by 0. 000 52 s for each increase of the 10° of the blade. The pressure on both blade surfaces will also decrease. For every 10° increase in the blade angle,the pressure pulsation time of the centrifugal pump is delayed backward by 0. 007 s at the solid-liquid two-phase flow. The main pulsating amplitude at different packet angles appears at the frequency shift. When the particle concentration is 0. 02 and 0. 05,the minimum value of pressure pulsation appears when the blade packet angle value is 140°. With the particle concentration of 0. 1,the pulsating amplitude decreases with the increase of the blade packet angle. When the blade packet angle increases from 130° to 160°,the pressure pulsation is most seriously affected by the blade packet angle,with the pulsating amplitude reduction of 14. 52%.Therefore,the pressure pulsation of solid-liquid two-phase centrifugal pump can be improved by increasing the blade packet angle appropriately at high particle concentration.
作者
万丽佳
宋文武
李金琼
WAN Li-jia;SONG Wen-wu;LI Jin-qiong(School of Energy and Power Engineering,Xihua University,Chengdu,China,Post Code:610039)
出处
《热能动力工程》
CAS
CSCD
北大核心
2019年第7期37-44,共8页
Journal of Engineering for Thermal Energy and Power
基金
四川省科技厅项目(2016JY0187)
四川省教育厅重大培育项目(14CZ0013)~~
关键词
离心泵
固液两相
叶片包角
压力脉动
颗粒浓度
centrifugal pump
solid-liquid two-phase
blade packet angle
pressure pulsation
particle concentration
