C形钝体绕流的尾涡结构与水动力特性分析
Numerical Investigation on Wake Flow Structure and Hydrodynamic Characteristics of Flow Around C-shaped Cylinder
高岳 1朱红钧 1周新宇 2周迈1
作者信息
- 1. 西南石油大学,成都 610500
- 2. 中国石油大港油田分公司第四采油厂(滩海开发公司),天津 300280
- 折叠
摘要
该文以不同攻角(0°＜α＜180°)的C形钝体在低雷诺数(40＜Re＜160)条件下的绕流流场为研究对象,数值分析了边界层分离点、尾涡结构及水动力系数的变化规律.结果表明:C形钝体的近场尾涡模式与攻角和雷诺数密切相关,根据边界层分离和近场尾涡结构,可将尾流模式分为9种,即Ⅰ型、Ⅱ-1型、Ⅱ-2型、Ⅲ-1型、Ⅲ-2型、Ⅳ型、V型、Ⅵ型和Ⅶ型;特征参数变化与近场尾涡模式相关,准静态涡出现时,回流区长度、尾迹长度较大,但尾迹宽度较小,而平均阻力系数和均方根升力系数最大值分别出现在Ⅰ型和Ⅱ-2型尾涡模式时;远场涡脱模式主要为2S模式,低雷诺数时无涡脱,而Re=60、α=150°时,涡脱模式为P+S,且出现了二次涡街.
Abstract
In this paper,a numerical investigation is conducted on the flow over a C-shaped cylinder in the low Reynolds number(Re=40-160)and the effect of attack angle(α)ranging from 0° to 180° is examined simultaneously.The wake evolution,vortex structure as well as the hydrodynamic characteristics are discussed.The results show that the near-wall wake structure is closely associated with Re and α.Night flow patterns are identified based on the location of boundary layer separation points and the evolution of near-wall vortices,including Pattern Ⅰ,Pattern Ⅱ-1,Pattern Ⅱ-2,Pattern Ⅲ-1,Pattern Ⅲ-2,Pattern Ⅳ,Pattern V,PatternⅥ,Pattern Ⅶ.Additionally,the characteristic parameters are related to the flow pattern partition.When quasi-static(QS)vortexes occur,the length of vortexes formation and the length of recirculation bubbles are enlarged,while the wake width is relatively small.The maximum mean drag coefficient occurs in the region of Pattern Ⅰ,and the maximum root-mean-square lift coefficient is observed in the region of Pattern Ⅱ-2.The far-field vortex shedding mode is mainly the 2S vortex mode,and no vortex shedding is found in the low Reynolds number cases.The P+S vortex mode and secondary vortex street occur when Re=60 and α=150°.
关键词
C形钝体/尾涡结构/水动力特性Key words
C-shaped cylinder/Wake flow structure/Hydrodynamic characteristic引用本文复制引用
基金项目
国家自然科学基金(51979238)
国家自然科学基金(52301338)
四川省杰出青年科学基金(2023NSFSC1953)
出版年
2024
NETL
NSTL
万方数据