椭圆管束层流尾迹的流动过渡和分岔  

Flow Transition and Bifurcation of Laminar Wake in Elliptical Tube Bundles

作　　者：李易蓉 杨茉[1] 张政[1] LI Yirong;YANG Mo;ZHANG Zheng(School of Energy and Power Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China)

机构地区：[1]上海理工大学能源与动力工程学院,上海200093

出　　处：《动力工程学报》2021年第4期294-300,共7页Journal of Chinese Society of Power Engineering

基　　金：国家自然科学基金资助项目(51736007)。

摘　　要：运用有限容积法,在不同无量纲管间距下对空气横掠椭圆管束进行二维数值模拟,对尾迹的流动变化过程和相应的分岔现象进行了分析。结果表明:保持初始边界条件不变,在无量纲管间距为0.5~3.5时,随着雷诺数增大至相应的临界值,Hopf分岔的发生使得尾迹从稳定的对称流动进入准周期状态;管间距较小时系统还会发生音叉分岔,间隙流动的偏离加剧了流动状态的不稳定性,随着雷诺数的进一步增大,尾迹中稳定的偏离快速过渡到不稳定的偏离,系统从准周期状态进入混沌状态;无量纲管间距较大时,同相和反相流动的出现使得尾迹扰动更规律,间隙流动会随着后方尾迹发生摆动,系统不再发生音叉分岔,系统最终进入准周期状态。The finite volume method(FV M)was used to simulate the air flowing across elliptical tube bundles at different dimensionless tube spacings,so as to analyze the flow change process of the wake and the corresponding bifurcation phenomenon.Results show that keeping the initial boundary conditions unchanged,when dimensionless tube spacing varies from 0.5-3.5,as the Reynolds number increases to the corresponding critical value,the occurrence of Hopf bifurcation makes the wake from stable symmetrical flow to unstable state.When the tube spacing is small,the fork bifurcation occurs,and the deviation of the tube flow would aggravate the instability of the flow state.With further increase of the Reynolds numb er,the stable deviation in the wake quickly transits to unstable deviation,and the system changes from quasi-periodic state into chaos.When the tube spacing is large,the appearance of in-phase and reversephase flow increases the regularity of wake disturbance.The tube flow will oscillate up and down with the rear wake,and the system will not be bifurcated with tuning fork.The flow state will eventually enter a quasi-periodic state.

关 键 词：椭圆管 层流 管间距 雷诺数 分岔 非线性动力学 

分 类 号：TK124[动力工程及工程热物理—工程热物理]