论文标题
可混杂的分子流体之间的超低有效界面张力
Ultra-low effective interfacial tension between miscible molecular fluids
论文作者
论文摘要
我们利用在较密集的背景流体中旋转的滴剂的变形，以研究可混杂的分子液之间的有效界面张力（EIT）。我们发现，对于足够低的界面张力，旋转滴剂会形成哑铃形状，两个大头部由一个较薄的中央体连接在一起。我们表明，这种形状不仅取决于液滴和背景流体之间的密度和粘度对比，还取决于流体分子结构，因此由于不同的分子相互作用而在其界面上发生的应力。我们系统地研究了在纯甘油储层中旋转的水甘油混合物的哑铃形滴的动力学。通过基于相反的变形的剪切应力的平衡来开发变形的模型，对跌落的正常应力和有效的界面张力，我们利用了液滴形状的时间演变来测量EIT。我们的结果表明，水甘油系统中的EIT比以前的实验测量值低的数量级低，并且与通过[Phys中提出的相位场模型计算的值都非常吻合。 Rev. X 6，041057，2016]。
We exploit the deformation of drops spinning in a denser background fluid to investigate the effective interfacial tension (EIT) between miscible molecular fluids. We find that for sufficiently low interfacial tension, spinning drops develop dumbbell shapes, with two large heads connected by a thinner central body. We show that this shape depends not only on the density and viscosity contrast between the drop and background fluids, but also on the fluid molecular structure, and hence on the stresses developing at their interface due to different molecular interaction. We systematically investigate the dynamics of dumbbell-shaped drops of water-glycerol mixtures spinning in a pure glycerol reservoir. By developing a model for the deformation based on the balance of the shear stress opposing the deformation, the imposed normal stress on the drop and an effective interfacial tension, we exploit the time evolution of the drop shape to measure the EIT. Our results show that the EIT in water-glycerol systems is orders of magnitude lower than that reported in previous experimental measurements, and in excellent agreement with values calculated via the phase field model proposed in [Phys. Rev. X 6, 041057, 2016].
