对称Y型分岔微通道微滴分裂数值模拟与实验探究

Numerical Simulation and Experimental Investigation of Droplet Splitting in Symmetric Y-type Bifurcation Microchannels

利用ANSYS Fluent软件中的两相流VOF模型,建立了微流控芯片中微滴通过对称Y型分岔微通道的三维动力学模型,实现了微滴流动的动态模拟,微滴界面演化的模拟结果与实验结果相吻合验证了该模型的有效性。通过该模型研究了微滴通过对称Y型分岔微通道的分裂行为和微滴分裂过程中压力场、速度场的演化过程,揭示了微滴在4种不同流型和不同阶段下的破碎机理,得到了微滴各流型与毛细数Ca和微滴尺寸之间的关系;根据模拟得到的各类流型数据,在MATLAB中拟合得到了该模型下微滴破裂与非破裂边界的预测方程。研究结果不仅为微滴分裂提供了一种简便有效的方法,在生物医学、能源化工及食品工程等领域也具有潜在应用价值。

Using the two-phase flow VOF model in the ANSYS Fluent software, a three-dimensional dynamic model of the droplet in the microfluidic chip passing through the symmetric Y-type bifurcation microchannel was established, and the dynamic simulation of the droplet flow and the simulation result of the droplet interface evolution were realized. It was consistent with the experimental results to verify the effectiveness of the model. Through this model, the splitting behavior of the droplet passing through the symmetric Y-type bifurcation microchannel and the evolution process of the pressure field and velocity field during the droplet splitting process were studied, and the breaking mechanism of the droplet under four different flow patterns and diffe-rent stages was revealed. The relationship between the flow pattern of the droplet and the capillary number Ca and the droplet size was obtained;according to the various flow pattern data obtained by the simulation, the prediction of the droplet rupture and non-rupture boundary under the model was obtained by fitting in MATLAB equation. This research not only provided a simple and effective method for droplet splitting, but also had potential application value in the fields of biomedicine, energy chemical industry and food engineering.