The evolution of the vortex shedding characteristics of gas-liquid two-phase flow in staggered tube bundles arranged in revolutional aquare with different ratios of pitch to diameter was studied by use of high-speed imaging method. The process of vortex generation, entrainment and polymerization was reconstructed by the dynamic image, while the mechanism of vortex evolution analyzed, and the periodical characteristics of vortex shedding compared and analyzed by the digital image correlation method. Results show that Strouhal number increases with rising ratio of pitch to diameter, and decreases with growing void fraction. When void fraction is higher than 0.14, the periodical vortex shedding phenomenon vanishs. In addition, vortex shedding frequency increases with rising Reynolds number.%采用高速图像采集方法,研究了不同节距比时以旋转正方形排列的错列管束间气液两相流旋涡的演化特性,通过动态图像重建了旋涡生成、卷吸及聚合过程,分析了旋涡演化机理,并运用时间序列图像相关性对比分析了旋涡脱落的周期特征.结果表明:随着节距比的增大,斯特罗哈数增大;随着含气率的增大,斯特罗哈数减小;当含气率大于0.14时,不存在周期性旋涡脱落现象;随着雷诺数的增大,旋涡脱落频率增加.
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