摘要
本文数值模拟雷诺数Re=i00的条件下,脉动流振幅和频率分别为0.2≤A≤0.8和0≤fp≤20Hz时方柱绕流特性。通过数值计算得到方柱绕流的升、阻力系数,涡脱频率及尾涡特性,且稳定流下计算结果与文献结果一致。研究结果表明脉动流是一种有效的主动流动控制方法;在脉动流频率,p为1.2—2.6自然涡脱频率fsn时,旋涡脱落频率存在“锁定”现象;在锁定范围内,尾涡形成区域变短,时均阻力系数显著增大,且在脉动流频率等于两倍频率时,时均阻力系数达到峰值;随着振幅的增大,频率“锁定”范围增大。
Two-dimensional numerical simulation is performed to understand the effect of flow pulsation on the flow from a square cylinder at Re = 100. The effects of flow pulsation amplitude (0.2≤A≤0.8) and frequency (0≤fp≤20Hz Hz) on the flow are presented. The Strouhal number of vortices shedding, drag coefficient for non-pulsating flow are good agreement with the previously published data. The result shows that the pulsating flow is an effective active flow controlling method. In the range of fp/fsn=1.2~2.6, the lock-on phenomenon occurs and the vortex formation region becomes shorter. The time-averaged drag coefficient shows a peak when the pulsating frequency fp is about twice the natural vortex shedding frequency fsn. The lock-on regime broadens with the pulsation amplitude increases.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2014年第2期338-341,共4页
Journal of Engineering Thermophysics
基金
国家自然科学基金项目(No.50976080)
武汉工程大学科学研究基金(No.14125061)
关键词
方柱
脉动流
锁定
square cylinder
pulsating flow
lock-on