%A ZHAO Ruijie*,MIAO Heng, ZHANG Desheng,HUANG Jun,GAO Xiongfa %T Three-dimensional transient characteristics and unstable flow of annular linear induction pump %0 Journal Article %D 2019 %J Journal of Drainage and Irrigation Machinery Engin %R 10.3969/j.issn.1674-8530.19.0044 %P 841-847 %V 37 %N 10 %U {http://zzs.ujs.edu.cn/pgjx/CN/abstract/article_2774.shtml} %8 2019-10-25 %X A three-dimensional transient magnetic-fluid coupling model of ALIP is established by using COMSOL software based on finite element method. The model is verified by comparing the simulation results of integral outer stator ALIP model with the previous experimental data. On this basis, the ALIP model of the separated external stator is established, and the evolution process of Kelvin-Helmholtz-like instability is observed. The reverse flow and vortices on the circumferential plane(φ-z)always appear in the channel region corresponding to the air between the two stators, a wave-like swing of the flow is presented at the rear of the unstable flow region. The unsteady flow on the meridional plane(r-z)first appears near the outer duct wall. Finally, the formation mechanism of Kelvin-Helmholtz instability is analyzed from the perspective of force balance. The separated stator structure makes the magnetic field and Lorentz force non-uniformly distributed in the azimuthal and radial directions, and then affects the distribution of flow field, which eventually leads to unstable flow.