微细通道内蒸发薄液膜区壁面滑移及微流动特性  

SLIP AND MICRO FlOW CHARACTERISTICS NEAR A WALL OF EVAPORATING THIN FILMS IN A MICROCHANNEL

作　　者：赵俊杰[1] 彭晓峰[1] 段远源[1] 

机构地区：[1]相变与界面传递现象实验室,清华大学热能工程系,北京100084

出　　处：《工程热物理学报》2009年第7期1171-1174,共4页Journal of Engineering Thermophysics

基　　金：国家自然科学基金重点项目支持(No.50636020)

摘　　要：基于扩展Young-Laplace方程和动力学理论研究微通道中蒸发薄液膜区固液界面附近流动和传热特性,考虑压力特征、壁面滑移和温度跳跃建立物理模型。利用边界层近似,提出一种计算固液界面吸附微液层热阻的方法,导得固液界面的热阻和温度。数值模拟结果表明,壁面微流动会降低毛细压力梯度,增加壁面热阻,降低液相过热度,恶化液膜铺展和传热性能,在薄液膜区不可忽略。阐明壁面微流动含义,指出滑移系数与吸附流动微液层厚度的关系。Flow and heat transfer characteristics near the solid-liquid interface of an evaporating thin film in a mierochannel was investigated using an augmented Young-Laplace model and the kinetic theory. Considering the pressure characteristics, a physical model with boundary layer approximation was developed to obtain the solid-liquid interracial thermal resistance and temperature. The results show that, nficro flow near a wall reduces capillary pressure gradient and liquid superheat as well as increasing solid-liquid interfacial thermal resistance, worsening liquid film spreading and heat transfer characteristics, effects of which are not to be neglected in the evaporating thin film region. The meaning of the micro flow and the relation between slip coefficient and adsorbed liquid layer thickness are both elucidated further.

关 键 词：蒸发薄液膜 固液界面 滑移系数 壁面微流动 微通道 壁面温度跳跃 

分 类 号：TL421.2[核科学技术—核技术及应用]