Flow onset for a single bubble in a yield-stress fluid
Flow onset for a single bubble in a yield-stress fluid
复制标题
屈服应力流体中单个气泡的流动起始
DOI：
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发表时间：
2021
影响因子：
3.7
通讯作者：
I. Frigaard
中科院分区：
文献类型：
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作者：
A. Pourzahedi;E. Chaparian;A. Roustaei;I. Frigaard
摘要：我们使用计算方法来确定在屈服应力液体中保持静态浮力气泡所需的最小屈服应力。静态极限由气泡形状、无量纲表面张力（gamma$）和屈服应力与浮力应力的比值（Y$）决定。对于给定的几何形状，对于$Y > Y_c$，气泡是静态的，这是我们为一系列形状确定的。考虑到表面张力可以忽略不计，与扁圆形气泡相比，长形气泡需要更大的屈服应力来保持静态。非零的$gamma$增加$Y_c$，对于较大的$gamma$， yield-毛细管数（$Y/gamma$）决定静态边界。在这个极限中，尽管气泡的形状很重要，但气泡的方向并不重要。研究了二维平面气泡和轴对称气泡。
Abstract We use computational methods to determine the minimal yield stress required in order to hold static a buoyant bubble in a yield-stress liquid. The static limit is governed by the bubble shape, the dimensionless surface tension ($gamma$) and the ratio of the yield stress to the buoyancy stress ($Y$). For a given geometry, bubbles are static for $Y > Y_c$, which we determine for a range of shapes. Given that surface tension is negligible, long prolate bubbles require larger yield stress to hold static compared with oblate bubbles. Non-zero $gamma$ increases $Y_c$ and for large $gamma$ the yield-capillary number ($Y/gamma$) determines the static boundary. In this limit, although bubble shape is important, bubble orientation is not. Two-dimensional planar and axisymmetric bubbles are studied.
影响因子：
3.1
作者：
Y. Liu;N. Balmforth;S. Hormozi;D. Hewitt
通讯作者：
Y. Liu;N. Balmforth;S. Hormozi;D. Hewitt