On the topological number in Kelvin's circulation of inviscid fluids  

作　　者：Z B Guo 

机构地区：[1]State Key Laboratory of Nuclear Physics and Technology,School of Physics,Peking University,Beijing 100871,China

出　　处：《Communications in Theoretical Physics》2024年第12期174-178,共5页理论物理通讯(英文版)

基　　金：supported by the Natural Science Foundation of China(NSFC)under Grant No.12075013。

摘　　要：Kelvin's circulation,as a loop integral of the velocity field,is first shown to be equal toΓc=2πΔnΓ1+constant in an inviscid fluid,withΓ1a unit circulation.The integerΔn is interpreted as the number of net 27r-rotations of the velocity vector in one cyclicality along the circulation loop and hence it is a topological number.Different from the linkage number in the helicity invariant,which only exists in 3D space,the topological number in the circulation invariant is independent of the spatial dimension.A further study reveals that this new topological phase 2πΔn is rooted at the gauge invariance of the circulation and it is a counterpart of the Berry's phase in the quantum system.

关 键 词：TOPOLOGICAL INVARIANT NUMBER 

分 类 号：O411[理学—理论物理]