摘要
基于高速离心泵的比转速十分高,通常高速离心泵的进口处和内部是回流漩涡和空化空蚀等现象的高发区域。孔板等空化抑制装置是否能针对回流漩涡起一定的抑制作用的研究还比较少。采用对诱导轮的前置空化抑制装置进行优化,共设计了改变装置前、后倾角等几何参数的25种方案进行数值模拟计算分析。优选出水力性能最好的5种方案并进行了回流漩涡范围和强度的分。其中着重研究了α角度的改变是否会影响相关的的回流速度和压力。同时对高速离心泵诱导轮、叶轮内部空化发生及发展的影响分析。最终确定了−10°/20°和−20°/10°的两个最优方案,在对回流漩涡的强度和影响范围方面表现均优于其他方案;气相体积分数在诱导轮和叶轮的内部分布面积很少,强度较低;设计工况下,相较于0°/0°方案,泵的效率约提高了2%,更好地抑制回流漩涡并提高了高速泵的抗空化性能,为高速离心泵内部空化的优化设计提供一定的参考意义。
The high specific speed of the high-speed centrifugal pump is very high.Therefore,the inlet and the inside of the high-speed centrifugal pump are usually high-incidence areas such as recirculation vortex and cavitation cavitation.As far as the current research status is concerned,whether the cavitation suppression device such as the orifice plate can suppress the reflux vortex is relatively rare.The pre-cavitation suppression device for the induction wheel is optimized.A total of 25 schemes for changing the geometric parameters such as the front and rear inclination angles of the device are designed for numerical simulation analysis.Based on this,it is preferable to select the five schemes with the best hydraulic performance and to carry out the fraction of the reflux vortex and the intensity.It focuses on whether the change in the alpha angle affects the associated reflow rate and pressure.At the same time,the influence of the high-speed centrifugal pump induction wheel and the internal cavitation occurrence and development of the impeller is analyzed.Finally,two optimal schemes of−10°/20°and−20°/10°are determined,which are superior to other schemes in terms of the strength and influence range of the reflux vortex;the gas phase volume fraction is inside the induction wheel and the impeller.The distribution area is small and the strength is low.Under the design condition,the efficiency of the pump is increased by about 2%compared with the 0°/0°scheme,which better suppresses the reflux vortex and improves the anti-cavitation performance of the high-speed pump.It provides a certain reference for the optimization design of internal cavitation of high-speed centrifugal pump.
作者
宋文武
石建伟
魏立超
胡帅
罗旭
陈建旭
SONG Wenwu;SHI Jianwei;WEI Lichao;HU Shuai;LUO Xu;CHEN Jianxu(School of Energy and Power Engineering,Xihua University,Chengdu 610039)
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2020年第4期95-103,共9页
Journal of Mechanical Engineering
关键词
高速离心泵
回流漩涡
空化抑制装置
倾角
high-speed centrifugal pump
hackflow vortex
havitation suppression device
dip angle