疏水表面滑移流动及减阻特性的格子Boltzmann方法模拟  

Lattice Boltzmann simulation of slip flow and drag reduction characteristics of hydrophobic surfaces

作　　者：黄桥高[1,2] 潘光[1] 宋保维[1] 

机构地区：[1]西北工业大学航海学院,西安710072 [2]九州大学,应用力学研究所,日本福冈816-8580

出　　处：《物理学报》2014年第5期226-232,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:51279165,51109178)资助的课题~~

摘　　要：采用格子Boltzmann方法研究了固体壁面对流体的作用强度与其润湿性的关系,在此基础上进一步模拟了疏水表面微通道内的流体流动,获得了润湿性对疏水表面滑移流动及减阻特性的影响规律,证实了疏水表面表观滑移的存在性并揭示了其产生机理.结果表明,疏水性作用在疏水表面的近壁区诱导了一个低密度层,而表观滑移则发生在低密度层上.表观滑移是疏水表面具有减阻作用的直接原因,减阻效果随滑移长度的增大而增大.对于特定的流体系统,滑移长度是疏水表面的固有属性,仅是壁面润湿性的单一函数,而与流动本身的性质无关.The relationship between the surface wettability and the interaction strength of liquid-wall particles is first investigated using a lattice Boltzmann method, and then the liquid fiow over hydrophobic surfaces is simulated in a microchannel. Efiect of surface wettability on the slip fiow and drag reduction characteristics of hydrophobic surfaces is obtained. Existence of the apparent slip on hydrophobic surfaces is confirmed and its mechanism is revealed. Simulation results show that the hydrophobicity induces a low density layer near the wall of hydrophobic surfaces and the apparent slip is observed on the low density layer. It is shown that the apparent slip is a direct cause of hydrophobic surfaces＇ drag reduction efiect. Thus the drag reduction efiect increases with increasing slip length. For a specific fiuid system,the slip length is an inherent property of the hydrophobic surfaces and is a single function of the surface wettability.The slip length does not change with the external fiow property.

关 键 词：疏水表面 滑移流动 减阻机理 格子BOLTZMANN方法 

分 类 号：O35[理学—流体力学]