风力机翼型非定常流场POD和EPOD分析  

Analysis of POD and EPOD for Unsteady Flow Field of Wind Turbine Airfoil

作　　者：孙翀 田甜 竺晓程[1] 杜朝辉[1] SUN Chong;TIAN Tian;ZHU Xiaocheng;DU Zhaohui(School of Mechanical Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]上海交通大学机械与动力工程学院,上海200240

出　　处：《上海交通大学学报》2022年第1期45-52,共8页Journal of Shanghai Jiaotong University

基　　金：国家自然科学基金资助项目(11872249)。

摘　　要：风力机翼型绕流对整机性能以及气动噪声水平具有重要的影响.采用大涡模拟与Ffowcs Williams-Hawkings(FW-H)方程相结合的方法,求解风力机翼型的非定常流场及远场气动噪声.通过本征正交分解(POD)方法提取翼型在8°攻角下的涡量流场模态.模态结构表明,尾缘涡团和层流分离泡是翼型主要流动的非定常特征.通过扩展本征正交分解(EPOD)方法获得与远场气动噪声最相关的模态结构,揭示与气动噪声产生及传播最相关的边界层中的涡结构与尾迹中的大尺度涡团.The profile flow around the wind turbine airfoil has a significant impact on the overall performance and the noise of a wind turbine.In this paper,a combination method of large eddy simulation(LES)and the solution of Ffowcs Williams and Hawkings(FW-H)equation is used to obtain the unsteady flow field and the far-field aeroacoustic noise of a wind turbine airfoil.The dominant modes of the unsteady vorticity at the angle of attack of 8°are extracted by the proper orthogonal decomposition(POD).The modal structure of the dominant modes indicates that the trailing edge vortices and the laminar separation bubble are the main unsteady feature of the airfoil flow.The modal structures most related to the far-field aeracoustics noise are obtained by the extend proper orthogonal decomposition(EPOD).The modal results show that the vortices in the boundary layer and the large-scale vortices in the wake are most relevant to the generation and propagation of the aeracoustics noise.

关 键 词：翼型绕流 大涡模拟 气动噪声 本征正交分解 

分 类 号：TK83[动力工程及工程热物理—流体机械及工程]