Investigation on the relationship between hydraulic loss and vortex evolution in pump mode of a pump-turbine  

作　　者：Yong-lin Qin De-you Li Hong-jie Wang Zhan-sheng Liu Xian-zhu Wei Xiao-hang Wang 

机构地区：[1]School of Energy Science and Engineering,Harbin Institute of Technology,Harbin 150001,China [2]State Key Laboratory of Hydro-Power Equipment,Harbin Institute of Large Electrical Machinery,Harbin 150040,China

出　　处：《Journal of Hydrodynamics》2022年第4期555-569,共15页水动力学研究与进展B辑（英文版）

基　　金：the National Natural Science Foundation of China(Grant No.51876047);the China Postdoctoral Science Foundation Funded Projection(Grant No.2018M630353);the Industrial Prospect and Key Core Technology of Jiangsu Province(Grant No.BE2019009-1).

摘　　要：Hydraulic loss and vorticity are two most common methods in analyzing the flow characteristics in hydro-machine,i.e.,centrifugal pump,Francis turbine,etc.While the relationship and correlation between hydraulic loss and vortex evolution are not uncovered yet.In this study,hydraulic loss is regarded as the combination of dissipation effect and transportation effect in flow domains.Meanwhile,vorticityωcan be decomposed into two parts,namely the Liutex partω_(R),the shear partωs,of whichω_(R)is regarded as the third-generation vortex identification method for its precise and rigorous definition of local rigid rotation part of fluid.Based on the dimensional analysis,two new physical quantities related to vorticity(ω,ω_(R)andωS),namely enstrophyΩ,vorticity transport intensity T are adopted to express the energy characteristic in vortex evolution process.Finally,operating points at pump mode of an ultra-high head reversible pump-turbine are selected as the research object and the numerical results calculated using SST k-ωturbulence model are consistent well with the experimental data.Pearson correlation coefficient is adopted to evaluate the correlation between hydraulic loss and vortex evolution in main flow regions.Results show that apart from the spiral casing domain,the enstrophy of shear partΩs has very strong correlation with dissipation effect and Liutex transport intensity TR has stronger correlation with transportation effect when compared with other forms of vorticity.The correlation between Liutex transport intensity TR and transportation effect is strong in stay/guide vanes(SGVs)while reduce to medium level in runner and draft tube domains.In spiral casing domain,all forms of vorticity show weak or very weak correlation with transportation effect.Based on the proposed method,we believe that the relationship and correlation between hydraulic loss and vortex evolution in other hydraulic machineries can also be clearly investigated.

关 键 词：Hydraulic loss ENSTROPHY vorticity transportation pearson correlation coefficient 

分 类 号：TH311[机械工程—机械制造及自动化]