基于POD方法的湍流大尺度信息提取与分析  

EXTRACTION AND ANALYSIS OF TURBULENT LARGE SCALES BASED ON POD METHOD

作　　者：阳祥[1] 丁鹏[1] 李增耀[1] 陶文铨[1] 

机构地区：[1]西安交通大学动力工程多相流国家重点实验室

出　　处：《工程热物理学报》2010年第6期1019-1022,共4页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助项目(No.50636050)

摘　　要：本文用正交分解（POD）方法对径向旋转方通道内直接数值模拟得到的湍流数据进行处理得到了湍流大尺度结构和POD模态的能量分布。对于不同的工况，文中均采用了200个具有相同时间间隔的湍流瞬时主流速度场作为样本。为研究浮升力对湍流火尺度结构的影响及POD模态的能量分布，对四个不同格拉晓芙数Grτ下的主流速度场进行了POD处理和分析。结果表明：湍流大尺度结构主要集中在通道的非稳定壁面（y=0）附近和侧壁面附近，随着格拉晓芙数的增加湍动能分布于更多的模态中。Proper orthogonal decomposition （POD） was used to deal with the databases obtained by direct numerical simulation in an orthogonally rotating turbulent duct flow. The turbulent large-scale structures and energy distribution in POD modes were extracted and analyzed. For every case studied, 200 turbulent instantaneous axial velocity snapshots with the same time interval were taken as samples. In order to investigate the influence of buoyancy on turbulent large-scale structures and the energy distributions in POD modes, four cases with different Grashof numbers were studied. The results show that the turbulent large-scale structures mainly locate in the unstable wall （y=0） and near the side walls; with the increase of the Grashof number, the most of the turbulent kinetic energy distributes into more POD modes.

关 键 词：湍流 浮升力 大尺度信息 正交分解 模态 

分 类 号：TK121[动力工程及工程热物理—工程热物理]