农业机械学报2017，Vol.48Issue(9)：111-120,10.DOI:10.6041/j.issn.1000-1298.2017.09.014
离心泵叶片表面布置障碍物抑制空化的数值模拟与实验
Effect of Surface-fitted Obstacle in Centrifugal Pump on Cavitation Suppression
摘要
Abstract
Centrifugal pumps are widely used to deliver liquid media in agriculture,pharmacy,industry,petrochemical industry,etc.Compared with the case delivering pure liquid such as water,centrifugal pumps not only have lower efficiency but also are subject to severe vibration,noise and erosion when delivering cavity two-phase flow,leading to the deterioration of flow field and even the shortage of service life.The cavitation flow in centrifugal pump performs strong instabilities,thus a method of a tiny obstacle fitted on the blade surface was proposed to suppress the cavitation development on a ns =32 model pump.The unsteady cavitation flow varied with cavitation number in centrifugal pump was simulated by modified SST k-ω turbulence model combined with Kubota cavitation model.The results showed that the head of centrifugal pump with obstacle was decreased within 5％ at various flow rate and within 3％ at design point,the efficiency was decreased within 3％ at various flow rate and 1.2％ at design point,the head with obstacle was great improved when cavitation flow developed.The obstacle can enhance the turbulent kinetic energy near the blade wall and reset the absolute pressure distribution,which can suppress the cavitation at different stages in centrifugal pump.The obstacle can optimize the flow structure and degrade the vortex intensity near the suction side of blade especially the area close to the tongue.The obstacle can decrease the cavity volume at varied cavitation number and the cavity volume keep attenuating when cavitation developed.The obstacle can cause small magnitude of the disturbance on the pressure frequency spectrum.The effects of cavitation suppression were optimal when the bubbles reached close to the obstacle.关键词
离心泵/障碍物/空化抑制/数值模拟Key words
centrifugal pump/obstacle/cavitation suppression/numerical simulation分类
机械制造引用本文复制引用
赵伟国,赵国寿,咸丽霞,韩向东..离心泵叶片表面布置障碍物抑制空化的数值模拟与实验[J].农业机械学报,2017,48(9):111-120,10.基金项目
国家自然科学基金项目(51269011) （51269011）
