A decomposition method of vortex identification and its application in side channel pumps  

作　　者：Ke Chen Fan Zhang Yu-jian Fang Desmond Appiah Shou-qi Yuan Feng Hong 

机构地区：[1]National Research Center of Pumps,Jiangsu University,Zhenjiang,212013,China [2]Quality Inspection Center for Pump Products in Zhejiang Province,Wenling,317599,China [3]College of Mechanical and Power Engineering,China Three Gorges University,Yi Chang,443000,China

出　　处：《Journal of Hydrodynamics》2022年第6期1106-1120,共15页水动力学研究与进展B辑（英文版）

基　　金：supported by the Ranking the Top of the List for Science and Technology Projects of Yunnan Province(Grant No.202204BW050001);the Taizhou Science and Technology Project(Grant Nos.21gyb05,21gyb08);the Research Innovation Program for College Graduates of Jiangsu Province(Grant No.KYCX22_3641);gratefully acknowledge financial support from China Scholarship Council;Project supported by the National Natural Science Foundation of China(Grant Nos.52279086,52150410397).

摘　　要：This research utilizes theΩvortex identification method to address the turbulent flows in a single-stage side channel pump,to comprehensively characterize the three types of dynamic vortex structures classified based on directions.Premised on the Galilean invariance,the work employs coordinate rotation and transformation.Thus,the indistinguishable 3-D vortex can be simplified to 2-D vortex on typical research planes.When juxtaposing the overall performance,it was revealed that a diversity of areas with high values yielded enhanced reflection of the vortex intensity,as measured by velocity distribution.The axial vortex structure with high intensity exists at the outer radius under all conditions largely.While the longitudinal vortex usually shows high intensity between the middle and outer radius.Simultaneously,the radial vortex is more likely to be at the inner radius near the suction face.Finally,this paper introduces a specific valueξ,which represents the ratio of decomposition to the total of the manifestation of the fluid rotational pattern.From the fluctuation and mean value,it can be realized that the development of the specific vortex in three directions at different positions.For example,the specific valueξ2 refers to the typical longitudinal vortex as dynamic vortex are almost from 20%to 50%,which illustrates that the longitudinal vortex only occupies a minor percentage in the total vortex.This phenomenon is one of the main reasons for the low efficiency.The present work could provide some suggestions and references for in-depth studies in fluid engineering with intense swirling flows.

关 键 词：Side channel pumps unsteady flow Ω-criterion vortex evolution 

分 类 号：O357.1[理学—流体力学]