【摘要】 采用基于嵌入式迭代的浸入边界法对均匀流场中圆柱群的横向流致振动进行了二维直接数值模拟。圆柱群中相邻柱体正交排列，间距比为L/D=3.20、8.00,折合流速为U_r=2～11,Re=100,圆柱质量比m~*=2。研究发现：不同间距比下，圆柱群前排和后排的圆柱分别呈现出涡激振动和尾流驰振的响应特征；后排圆柱的振幅普遍大于前排圆柱，小间距比圆柱群的最大振幅高于大间距比的情况；前排相邻圆柱(横流向)的脱涡模式为稳定的同相同步和反相同步模式，或者两种同步模式的切换。顺流向上，小间距比前排相邻圆柱分别呈现延展体和重附着模式，而大间距比下均为共同脱涡模式。各圆柱的主频f~*、振幅与升力-位移相位差之间存在紧密的联系。随着U_r的增大，圆柱升力-位移相位差会从0°跳转到180°,分别对应流体对圆柱振动的激励和抑制作用，其中后排圆柱完成相位转换需要过渡的折合流速区间更大。相邻并列圆柱之间存在微小的振动频率差，其位移之间的相位差不稳定。随着U_r的增大，大间距比圆柱群相位差稳定的范围总体向上游缩窄，而小间距比时则向下游扩张。更多还原

【Abstract】 Here, 2D direct numerical simulation was performed for transverse flow induced vibration of a cylinder arrays in a uniform flow field with the embedded iteration-based immersion boundary method. Adjacent cylinders in cylinder arrays were arranged orthogonally, with spacing ratio of L/D=3.20, 8.00, equivalent flow velocity of U_r=2-11, Re=100 and cylinder mass ratio of m~*=2. The study showed that under different spacing ratios, cylinders in front and rear rows of cylinder arrays exhibit response characteristics of vortex induced vibration and wake flutter, respectively, amplitudes of rear row cylinders are generally larger than those of front row cylinders, the maximum amplitude of cylinder arrays with small spacing ratio is higher than that of cylinder arrays with large spacing ratio; under different spacing ratios, vortex shedding modes of adjacent cylinders in front row(transverse flow direction) are stable in-phase synchronous and anti-phase synchronous modes, or a switch between the two synchronous modes; if flowing up stream, adjacent cylinders with small spacing in front row exhibit extended and reattached modes, while those with larger spacing exhibit a common vortex shedding mode; close relations exist among main frequency f~*, amplitude and lift-displacement phase difference of each cylinder; with increase in U_r, lift-displacement phase difference of cylinder can jump from 0° to 180° corresponding to excitation and suppression effects of fluid on cylinder vibration, and rear row cylinders require a larger transition equivalent flow velocity range to complete phase conversion; there is a very small difference between vibration frequencies of adjacent parallel cylinders, and phase difference between their displacements is unstable; with increase in U_r, phase difference stable range for cylinder arrays with large spacing ratio generally narrows upstream, while that for cylinder arrays with small spacing ratio expands downstream.更多还原