μ-PIV measurements of the ensemble flow fields surrounding a migrating semi-infinite bubble.
μ-PIV measurements of the ensemble flow fields surrounding a migrating semi-infinite bubble.
复制标题
对迁移的半无限气泡周围的整体流场进行 μ-PIV 测量。
DOI：
10.1007/s00348-009-0662-1
复制
发表时间：
2009
影响因子：
2.4
通讯作者：
Gaver3rd,DonaldP
中科院分区：
文献类型：
--
作者：
Yamaguchi,Eiichiro;Smith,BradfordJ;Gaver3rd,DonaldP
微尺度粒子图像测速测量法通过计算机控制的线性马达流量控制系统的新的适应性对稳定迁移的半无限气泡周围的总体流场进行测量。该系统被编程为产生方波速度输入，以产生准确的恒定的气泡传播反复和有效地通过熔融玻璃毛细管。通过分析气泡界面中心线速度剖面标准差的突然变化，提出了一种新的技术，用于在每个瞬时场中将坐标轴重新定位到气泡尖端参考系。然后在该气泡尖端参考系中计算包围平均值。使用水/空气、甘油/空气和甘油/硅油的组合流体系统来研究与Smith和Gaver III（J Fluid Mech 601：1-23，2008）中描述的计算模拟以及与界面形状的过去实验观察相当的流动。还分析荧光颗粒图像以测量气泡后面的残留膜厚度。流场和膜厚与计算模拟以及现有的实验和分析结果吻合得很好。颗粒的积累和迁移与气泡尖端附近的流型经过长时间的实验时间进行了讨论，作为潜在的误差源的实验方法。
Microscale particle image velocimetry measurements of ensemble flow fields surrounding a steadily migrating semi-infinite bubble through the novel adaptation of a computer controlled linear motor flow control system. The system was programmed to generate a square wave velocity input in order to produce accurate constant bubble propagation repeatedly and effectively through a fused glass capillary tube. We present a novel technique for re-positioning of the coordinate axis to the bubble tip frame of reference in each instantaneous field through the analysis of the sudden change of standard deviation of centerline velocity profiles across the bubble interface. Ensemble averages were then computed in this bubble tip frame of reference. Combined fluid systems of water/air, glycerol/air, and glycerol/Si-oil were used to investigate flows comparable to computational simulations described in Smith and Gaver III (J Fluid Mech 601:1–23, 2008) and to past experimental observations of interfacial shape. Fluorescent particle images were also analyzed to measure the residual film thickness trailing behind the bubble. The flow fields and film thickness agree very well with the computational simulations as well as existing experimental and analytical results. Particle accumulation and migration associated with the flow patterns near the bubble tip after long experimental durations are discussed as potential sources of error in the experimental method.