双吸离心泵空化特性的试验及数值模拟  

Experiment and numerical simulation of cavitation performance for a double suction centrifugal pump

作　　者：孟根其其格 谭磊[1] 见文 刘卫伟 魏培茹 曹树良[1] 

机构地区：[1]清华大学水沙科学与水利水电工程国家重点实验室,北京100084 [2]内蒙古化工职业学院,呼和浩特010070 [3]上海东方泵业(集团)有限公司,上海201906

出　　处：《中国科学：技术科学》2015年第10期1111-1116,共6页Scientia Sinica(Technologica)

基　　金：国家自然科学基金(批准号:51176088);清华大学自主科研计划资助(批准号:2014z21041;20141081231);西华大学流体及动力机械教育部重点实验室开放课题(批准号:szjj2015-021)资助项目

摘　　要：试验测量了一台双吸离心泵的能量特性和空化特性.基于RNG k-ε湍流模型和质量输运空化模型,探讨了质量输运空化模型中凝结项经验系数对数值模拟结果的影响,结果发现凝结项经验系数主要影响叶轮内空泡长度.在此基础上,修正了双吸离心泵空化流动数值模拟中凝结项经验系数的取值,计算得到的双吸离心泵扬程随进口压力变化曲线与试验结果吻合较好,验证了数值计算模型和方法的准确性和可靠性.双吸离心泵空化流动数值模拟结果表明:随着泵进口压力的降低,空化首先在叶片吸力面进口附近的低压区发生,之后沿叶片吸力面往叶轮流道中部发展,并向叶片压力面扩散;受双吸离心泵蜗壳非对称结构的影响,叶轮内不同流道的空化区域分布不均匀.The energy and cavitation performances of a double suction centrifugal pump are tested on a standard experiment rig. The influence of condensation coefficient of the mass transport cavitation model on numerical simulation is analyzed by using the RNG k-ε turbulence model and the mass transport cavitation model. As a result, the condensation coefficient mostly regulates the cavity length in the impeller. According to the calculation result, the value of condensation coefficient is modified. The calculated variation of pump head and efficiency with pump inlet pressure decrease agrees well with the experimental data. The results demonstrate that the numerical model and method can accurately predict the cavitation flows in a double suction centrifugal pump. The flow field analysis indicates that the cavitation firstly appears at suction side of blade near the leading edge and then extend to the outlet of impeller with the further reduction of pump inlet pressure. Due to the influence of asymmetric volute structure, the vapor distribution in different flow passages is not uniform.

关 键 词：双吸离心泵 试验 数值模拟 空化模型 凝结项经验系数 

分 类 号：TH311[机械工程—机械制造及自动化]