Numerical investigation of dynamic behavior of a compound drop in shear flow

作者：Vu Truong V^*; Vu Luyen V; Pham Binh D; Luu Quan H^*

来源：Journal of Mechanical Science and Technology, 2018, 32(5): 2111-2117.

DOI：10.1007/s12206-018-0420-5

• Compound drop
• Numerical investigation
• Front-tracking
• Breakup
• Shear flow

We present a numerical investigation of the deformation and breakup of a compound drop in shear flow. The numerical method used in this study is a two-dimensional front-tracking/finite difference technique for representing the interface separating two fluids by connected elements. The compound drop with the initially circular and concentric inner and outer fronts is placed at the center of a domain whose top and bottom boundaries move in the opposite direction. Because of the shear rate, the compound drop deforms and can break up into drops, depending on the flow conditions based on the Reynolds number Re, the Capillary number Ca and the interfacial tension ratio sigma(21) of the outer to inner interfaces. We vary Re in the range of 0.1-3.16, Ca in the range of 0.05-0.6 and sigma(21) in the range of 0.8-3.2 to reveal the transition from the non-breakup to breakup regimes. Numerical results indicate that the compound drop breaks up into drops when there's an increase in Re or Ca or a decrease in sigma(21) beyond the corresponding critical values. We also propose a phase diagram of Ca versus Re that shows the region in which the compound drop changes from the deformation mode to the breakup mode.

• 出版日期2018-5