高速离心泵口环密封流体激振力特性研究  

Study on fluid-induced force dynamic characteristics of annular seal of high speed centrifugal pump

作　　者：程效锐[1,2] 王晓全 陈红杏 CHENG Xiao-rui;WANG Xiao-quan;CHEN Hong-xing(School of Energy and Power Engineering,Lanzhou University of Technology,Lanzhou 730050,China;Key Laboratory of Fluid Machinery and System of Gansu Province,Lanzhou 730050,China)

机构地区：[1]兰州理工大学能源与动力工程学院,甘肃兰州730050 [2]甘肃省流体机械及系统重点实验室,甘肃兰州730050

出　　处：《水动力学研究与进展（A辑）》2019年第6期740-748,共9页Chinese Journal of Hydrodynamics

基　　金：国家自然科学基金(51469013)~~

摘　　要：在离心泵等旋转机械中口环通常作为一种减小泄露流量的部件,但随着口环间隙的减小和转子转速的增加,其动力学特性对高速离心泵的稳定运行影响不容忽视。基于数值模拟的方法计算研究了高速离心泵在工作状态下口环处产生的流体力,并讨论了减小口环处不稳定流体激振力的方法。通过整体建模高速离心泵流场域,计算了处于具体的进出口边界条件下的口环中转子在不同涡动半径、涡动比和口环密封尺寸下所受流体激振力。结果表明:单蜗壳式高速离心泵口环密封处产生的流体力占据了叶轮总体径向力的大部分,泵转子涡动时口环密封处产生频率等于轴频的交变力频率;口环密封激振力与转子涡动半径和涡动比有密切的关系;口环密封尺寸对口环流体激振力的影响显著,在相同口环间隙与长度比下,口环轴向长度的变化对口环所受流体力的影响比口环间隙大,同时,对口环密封性能影响小。The annular seal is usually employed to reduce leakage flow in centrifugal pumps.However,with the decrease of annular seal clearance and the increase of rotor rotational speed,the influence of its dynamic characteristics on the stable operation of high-speed centrifugal pumps should not be ignored.Based on the numerical simulation method,the unsteady fluid force generated at annular seal of the high-speed centrifugal pump’s impeller was studied in this paper,and the method to reduce the unstable fluid excitation force was also discussed.The whole computational domain of high-speed centrifugal pump which includes annular seal clearance was established to accurately simulate the inlet and outlet boundary conditions of the annular seal clearance.Meanwhile the influence of whirl radius,whirl ratio and seal dimension parameters on fluid force was studied too.The results show that the fluid force generated at the seal of single volute high-speed centrifugal pump occupies most of the total radial force of the impeller,and the frequency of alternating fluid force generated at the seal equals to the axial frequency when the pump rotor whirls;the magnitude of exciting force of the annular seal is closely related to the whirl radius and the whirl ratio;the size of the annular seal has a significant influence on the fluid exciting force of the annular seal.The change of the axial length of the annular seal has a greater effect on the fluid force than seal clearance at the same ratio of clearance to length,while has smaller impact on the sealing performance.

关 键 词：高速离心泵 口环密封 流体激振力 数值模拟 

分 类 号：TH3[机械工程—机械制造及自动化]