基于水平集方法的共轴流型液滴形态关键参数研究

采用水平集方法对共轴流形的液滴成形进行计算和研究.以液-液两相流为研究对象，离散相为石蜡和庚烷混合物，连续相为纯水溶液.对离散相液体的进样速度、黏度和进样孔径大小分别进行了计算分析.离散相液体分别以15 ~ 48mm/s的速度进入半径1mm的圆孔通道，随着流速增大，喷射高度变长，周期规律性降低.同时提高离散相溶液的黏度可以有效降低液滴张力与拖曳力之间的作用时间，增大液滴生成频率和改善液滴均匀性.孔径大小直接影响进样口层流的入口速度，缩小孔径将使进样流速变化剧烈，挤压后的液滴生成尺寸相对较小.

Research on the Critical Parameters for Droplet Formation in Co-Flow Based on Level Set Method

The generation of droplets in co-flow was studied by the level set method. Taking into account liquid-liquid two phases， the dispersed phased liquid is a mixture combined paraffin oil with heptane， whereas， the continuous phase fluid is aqueous water. Herein， these calculated works were carried out with inlet velocity and viscosity of the dispersed phase fluid， as well as injected hole size. When the dispersed phase fluid with velocity from 15mm/s to 48mm/s flows into a hole channel with radius of 1mm， the jetting height increases and the periodic generation reduces as the inlet velocity increases gradually. Meanwhile， increasing its viscous coefficient could decrease the disinfected time between droplet tension and drug force， so that frequency was increased and homogeneous characteristics were improved. The velocity of laminar flow was directly affected by the size of the hole. Owing to shrink the hole size， the sharpness of injected velocity occurs， resulting in the smaller size of the extruded droplet.