摘要
采用了高精度谱单元法,对间距比L/D=2. 5,雷诺数为150~300的四方柱进行了三维数值模拟研究。并从水动力系数、瞬态流型、能量曲线及三维涡结构等方面对四方柱的尾流特性及三维不稳定性模态的发展进行研究和分析。随着雷诺数的提高,尾流流型从反相位模式转变为同相位模式,对应的主导不稳定波数模态由波数5转变为波数4,该转变阶段主要发生在雷诺数为225左右,其特性充分体现在各雷诺数下的能量曲线及三维涡结构发展中。当间距比L/D=2. 5时,在雷诺数为150~300下并未出现mode A和mode B两种基本不稳定性,而主导波数5和波数4模态的特性均属于第三种基本不稳定性mode C。
In this paper, the high-order spectral element method is employed to study the three-dimensional numerical simulation for four square cylinders with fixed spacing ratio L/D = 2. 5. The Reynolds numbers are selected from 150 to 300,and the wake characteristics and the development of three-dimensional unstable modes for four square cylinders are investigated and analyzed combining the aspects of hydrodynamic coefficients,transient flow pattern,energy curve and three-dimensional vortex structure. As the Reynolds number increases,the wake flow pattern transforms from the anti-phase pattern to the in-phase pattern,corresponding dominant unstable wavenumber from wavenumber 5 to wavenumber4. The transition phase mainly occurs around the Reynolds number of 225,whose characteristics are fully reflected in the evolution of energy curves and three-dimensional vortex structures at various Reynolds numbers. At spacing ratio L/D = 2. 5,there are no two fundamental three-dimensional instabilities mode A and mode B under Re = 150 ~ 300. However, the characteristics of dominant wavenumber 5 and wavenumber 4 mode all belong to the third fundamental instability mode C.
作者
张宇航
王锐
韩兆龙
周岱
包艳
Zhang Yuhang;Wang Rui;Han Zhaolong;Zhou Dai;Bao Yan(Department of Civil Engineering,School of Naval Architecture,Ocean and Civil Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)
出处
《科技通报》
2020年第6期1-9,共9页
Bulletin of Science and Technology
基金
国家自然科学基金资助项目(11772193,51679139,51879160)
上海市自然科学基金(18ZR1418000,17ZR1415100)资助
上海交通大学新引进人员科研启动基金(WF220401005)
上海高校特聘教授(东方学者)岗位计划
上海市国际科技合作基金项目(18290710600)
关键词
四方柱
谱单元法
流型
三维不稳定模态
four square cylinders
spectral element method
flow pattern
three-dimensional unstable mode
作者简介
张宇航(1993-),男,江苏南通,硕士研究生,主要研究方向为钝体绕流模态分析,E-mail:yh.zhang@sjtu.edu.cn。;通信作者:周岱,教授,主要研究方向为大跨空间结构,海洋结构物流固耦合作用,海洋风电新技术,E-mail:zhoudai@sjtu.edu.cn。
