【作者】 高宇航； 冯凯； 张会臣；

【Author】 Gao Yuhang;Feng Kai;Zhang Huichen;Naval architecture and ocean engineering college,Dalian Maritime University;

【机构】 大连海事大学船舶与海洋工程学院；

【摘要】 微流控技术具有样品消耗量小、高通量、易控制、传热传质效率高和固有安全性等特点,广泛应用在生物医学和化学化工等领域。微通道内流体的流动特性与宏观尺度不同,可以实现常规尺寸通道无法实现的功能。本文采用格子Boltzmann方法对二维T型微通道内气液两相流的流动特性进行研究,分析气液流速、气液流速比和壁面特性对流型和压力降的影响。结果表明,气液流速和气液流速比是影响流型的重要因素,随着毛细数的增大,分散相脱离点逐渐远离两相入口,形成更长的分层流;壁面的疏水性使通道内形成的单个液滴呈现出不同的接触角;不同条件下沿微通道方向压力逐渐减小,在气液两相交汇区域压力存在波动;流速的峰值出现"滞后"现象,气液流速比越大会使速度波动越大。更多还原

【Abstract】 Microfluidic technology is widely used in biomedicine,chemical industry and other fields due to its low sample consumption,high throughput,easy control,high heat and mass transfer efficiency and inherent safety.The flow characteristics of fluid in microchannel are different from those in macro scale,which can achieve the functions that can not be achieved by conventional size channel.In this paper,lattice Boltzmann method is used to study the flow characteristics of gas-liquid two-phase flow in two-dimensional T-shaped microchannel,and the effects of gas-liquid velocity,gas-liquid velocity ratio and wall characteristics on the flow pattern and pressure drop are analyzed.The results show that the gas-liquid velocity and the gas-liquid velocity ratio are important factors affecting the flow pattern.With the increase of capillary number,the separation point of dispersed phase gradually moves away from the two-phase inlet,forming a longer stratified flow;The hydrophobicity of the wall makes the single droplet in the channel present different contact angles;Under different conditions,the pressure gradually decreases along the direction of the microchannel,and the pressure fluctuates at the gas-liquid two-phase junction;The larger the gas-liquid velocity ratio is,the greater the velocity fluctuation is.更多还原