The knowledge of flow interference between two circular cylinders is favorite to understand the flow mechanism and ensure the safety of cylinders.Flows around two cylinders of equal diameter are simulated by DVM (discrete vortex method).The interference effect of two cylinders is investigated by comparing the two cylindrical lift coefficient,the drag coefficient and Strouhal number and the vortex shedding structure.The reliability of the present method is reflexed by comparing with other experimental or numerical simulation data.To further study the impact of two cylindrical gap ratio (G/D),the flows around two side by side and tandem cylinders in a different range of G/D are calculted.Under a fixed gap ratio,the average drag force coefficients for both cylinders grows to an upper limit value as the increase of angle between free stream velocity and center line of twin cylinders,and the mean lift force coefficient rise again till getting close to zero after reaching a minimum.When the G/D gets larger,the interference effect weakens and flows around the two cylinders,which can be approximated as two single-flow around a cylinder.It provides reference for study of flow around two cylinders.%对双圆柱流动干涉效应的认识有利于了解多管流场的作用机制、确保结构安全.基于离散涡方法,对二维等直径双圆柱绕流的水动力特性进行数值分析.计算串列、并列以及交错排列下双圆柱流动干涉问题,通过对比2个圆柱的升力系数、阻力系数和斯特劳哈尔数以及尾涡结构,观察两圆柱体的干涉效应.对比试验和其他数值模拟结果验证本文方法的可靠性.为进一步研究两圆柱间隙比的影响,计算串列和并列圆柱在不同间隙比情况下的圆柱绕流问题.结果表明:间隙比一定时,随着来流与圆柱中心线夹角的增大,双圆柱的平均阻力逐渐增大并趋于稳定,平均升力在达到极小值后又开始增大并逐渐趋于0;当间隙增大时,干涉现象逐渐消失,双圆柱绕流可近似看作两个单圆柱绕流.为双圆柱绕流问题的研究提供参考.
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