3D flow structures behind a wall-mounted short cylinder
3D flow structures behind a wall-mounted short cylinder
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壁挂式短圆柱体后面的 3D 流动结构
DOI：
10.1016/j.oceaneng.2020.108535
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发表时间：
2021-02
影响因子：
5
通讯作者：
Yan Zheng
中科院分区：
文献类型：
--
作者：
Hiroka Rinoshika;Akira Rinoshika;Jinjun Wang;Yan Zheng
采用高分辨率层析粒子图像测速仪（Tomo-PIV），由4台高分辨率双曝光CCD相机组成，在雷诺数为10,720的情况下，测量了水洞内宽高比为1的壁挂式短圆柱后的三维流动结构。基于实测的瞬时三维速度分布，首先讨论了三维速度场、涡度、q准则、后分离区以及拱型涡和叶顶涡的特性。为了评价三维多尺度尾流结构和能流结构，采用三维正交小波多分辨技术和适当正交分解（POD）对Tomo-PIV的瞬时三维速度场进行了分析。在短圆柱后发现了一个三维w型拱涡，它是由上冲流和下冲流相互作用产生的。拱涡结构的头部形状与柱体的长径比有关。利用三维正交小波多分辨率分析，提取了小波一级大尺度结构中的瞬时拱涡和流向涡。研究还发现，中尺度上冲流对w型拱形涡头的形成起着重要作用。剪切层中出现了较强的小尺度构造，而中尺度构造则包含在其中。POD分析表明，前两个模态占总湍流脉动能量的13.3%，前四个POD模态表现出几个大尺度的流向涡。
A high-resolution Tomographic particle image velocimetry (Tomo-PIV), which consists of four high-resolution double-exposure CCD cameras, was used to measured three-dimensional (3D) flow structures behind a wall-mounted short cylinder of an aspect ratio 1 at Reynolds number 10,720 in a water tunnel. Based on the measured instantaneous 3D velocity distribution, 3D velocity fields, the vorticity, theQcriterion, the rear separation region and the characteristic of arch type vortex and tip vortices are first discussed. In order to evaluate 3D multi-scale wake flow structures and energetic flow structures, the 3D orthogonal wavelet multi-resolution technique and proper orthogonal decomposition (POD) are applied to analyze instantaneous 3D velocity fields of Tomo-PIV. A 3D W-type arch vortex behind the short cylinder is found, which is originated by the interaction between upwash and downwash flows. The head shape of arch vortex structure is associated with the aspect ratio of the cylinder. By using the 3D orthogonal wavelet multi-resolution analysis, the instantaneous arch vortex and streamwise vortices are extracted in the large-scale structures of the wavelet level 1. It also found that the intermediate-scale upwash flows play an important role in originating the head of W-type arch vortex. Strong small-scale structures appeared in the shear layer and were contained in the intermediate-scale structures. The POD analysis indicates that the first two modes account for 13.3% of the total turbulent fluctuating energy, and the first four POD modes exhibit several large-scale streamwise vortices.
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影响因子：
0.8
作者：
Hiroka Rinoshika;A. Rinoshika;S. Fujimoto
通讯作者：
Hiroka Rinoshika;A. Rinoshika;S. Fujimoto
影响因子：
2.4
作者：
R. Pattenden;S. Turnock;Xin Zhang
通讯作者：
R. Pattenden;S. Turnock;Xin Zhang
影响因子：
--
作者：
M. Yamada;K. Ohkitani
通讯作者：
M. Yamada;K. Ohkitani
DOI：
10.1299/jsme1958.27.2142
发表时间：
1984-10
期刊：
--
影响因子：
--
作者：
T. Kawamura;M. Hiwada;Toshiharu Hibino;I. Mabuchi;M. Kumada
通讯作者：
T. Kawamura;M. Hiwada;Toshiharu Hibino;I. Mabuchi;M. Kumada
DOI：
10.1016/j.ijheatfluidflow.2006.12.001
发表时间：
2007-10
影响因子：
2.6
作者：
A. Rinoshika;Yu Zhou
通讯作者：
A. Rinoshika;Yu Zhou