The unsteady flow field is calculated by the computational fluid dynamics (CFD) method, around a wind turbine airfoil at high angle of attack, and its modes are identified by using the dynamic mode decomposition (DMD) method. The dominant modes and corresponding frequencies are obtained. The results show that the DMD method can be used to analyze the changing process of the unsteady flow field; the DMD modes capture the main flow structure of the unsteady flow field, and the main unsteady flow is around the near wake region; the flow field, reconstructed by 4 DMD modes, could describe the original unsteady flow field; the flow field reconstructed by the second DMD mode describe that two vortexes, whose rotating directions are opposite, shed and spread into downstream in turn.
LIU Pengyin1，2,CHEN Jinge1,SHEN Xin1,ZHU Xiaocheng1,DU Zhaohui1
. Analysis of Dynamic Mode Decomposition for
Wind Turbine Airfoil Flow Field at High Angle of Attack[J]. Journal of Shanghai Jiaotong University, 2017
, 51(7)
: 805
-811
.
DOI: 10.16183/j.cnki.jsjtu.2017.07.006
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