Experimental investigation on droplet evolutions in co-flow around the bluff body
Experimental investigation on droplet evolutions in co-flow around the bluff body
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DOI：
10.1016/j.expthermflusci.2023.111106
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发表时间：
2023-11
影响因子：
3.2
通讯作者：
Hongbing Ding;Xinyu Song;Jinxia Li;C. Wen;Hongjun Sun;Zhihua Bao;Xixi Liu
中科院分区：
文献类型：
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作者：
Hongbing Ding;Xinyu Song;Jinxia Li;C. Wen;Hongjun Sun;Zhihua Bao;Xixi Liu
环状雾流广泛存在于天然气等工程领域。涡街流量计已逐渐成为湿气体测量的有效手段。然而，流场中的液滴会影响旋涡的稳定性。本文通过实验研究了液滴与旋涡的相互作用。为了提高液滴测量的精度，提出了一种新的聚焦判据。实现了液滴大小、速度和浓度的同时采集。获得了液滴参数的空间演化规律，以确定液滴均匀分布的位置。研究了液滴与旋涡的双向耦合机理。首先，通过钝体周围液滴的分布特征来反映涡流场对液滴的影响。其次，基于Stokes数Stp和液相载荷φL分析了液滴对流场中涡旋信号的影响，当φL=0.03时，钝体下游液滴速度的概率分布呈双峰分布。小液滴与旋涡之间的交换动量较大，大液滴与旋涡之间的交换动量较大。随着液滴体积浓度的增加，涡旋信号的品质因数从−2.09减小到−2.18。进一步证明，液滴体积浓度的增加会破坏涡旋结构，降低涡旋信号的质量。
Annular mist flow widely exists in natural gas and other engineering fields. Vortex flowmeter has gradually become an effective means of wet gas measurement. However, the droplets in the flow field will influence the stability of the vortex. In this paper, the interaction between droplets and vortex was studied by experiments. A novel in-focus criterion was proposed to improve the accuracy of droplet measurement. Simultaneous acquisition of droplet size, velocity, and concentration was achieved. The spatial evolution of droplet parameters was obtained to determine the position where the droplets were evenly distributed. The bidirectional coupling mechanism between droplets and vortex was studied. Firstly, the influence of the vortex flow field on droplets was reflected by the characteristics of droplet distribution around the bluff body. Secondly, the effect of droplets on the vortex signal in the flow field was analyzed based on Stokes number Stpand liquid-phase loadφl. Whenφl< 0.03, the probability distribution of droplet velocity downstream of the bluff body presents double peaks. The exchange momentum between the small droplets and the vortex is stronger, and vice versa for the larger droplets. Finally, the quality factor of vortex signals decreases from −2.09 to −2.18 with the increase in the volume concentration of droplets. It is further demonstrated that the increase in volume concentration of droplets will destroy the vortex structure and degrade the quality of the vortex signal.