烷烃液滴润湿特性的分子动力学模拟  

Wetting Characteristics of Alkanes Droplets: a Molecular Dynamics Study

作　　者：蔡伟华 何子彧 王嘉欣 高磊[1] 李倩 王悦 CAI Weihua;HE Ziyu;WANG Jiaxin;GAO Lei;LI Qian;WANG Yue(School of Energy and Power Engineering,Northeast Electric Power University,Jilin 132012,China)

机构地区：[1]东北电力大学能源与动力工程学院,吉林132012

出　　处：《工程热物理学报》2022年第5期1375-1384,共10页Journal of Engineering Thermophysics

基　　金：国家自然科学基金企业联合基金重点项目(No.U21B2087)。

摘　　要：本文利用分子动力学模拟研究烷烃液滴在不同壁面上的润湿特性。模拟发现:纯甲烷液滴的接触角随壁面势阱参数ε增大而减小,但减小的趋势和幅度逐渐减缓。随着温度升高,纯甲烷液滴的接触角在疏烷烃壁面上小幅增加,在中性壁面上基本不变,而在亲烷烃壁面上则小幅减小,即温度升高加强了甲烷对壁面的润湿倾向性。当在甲烷液滴中掺入乙烷后,随着乙烷占比增加,由于在疏烷烃壁面上甲烷和乙烷的润湿性差别很小,所以疏烷烃壁面上的接触角增加不明显。在中性壁面和亲烷烃壁面上,随乙烷占比增加,混合液滴的接触角逐渐增大。这是由于混合液滴中加入的乙烷对于甲烷起到“胶合剂”的作用,削弱了甲烷分子的运动,导致接触角增大。This article uses molecular dynamics simulation to study the wetting characteristics of alkanes droplets on different surfaces. The simulation found that the contact angle of pure methane droplets decreases as the potential energy depth parameter(ε) of the wetted surface increases, but the decreasing trend and amplitude gradually slow down. As the temperature increases, the contact angle of pure methane droplets slightly increases on the hydrophobic surface, basically unchanged on the neutral surface and slightly decreases on the hydrophilic surface. That is, the increase in temperature strengths the wetting tendency of methane for the surface. When ethane is mixed into methane droplets, as the proportion of ethane increases, the difference in wettability between methane and ethane on the hydrophobic surface is very small, so the contact angle of the mixed droplet on the hydrophobic surface does not increase significantly. On neutral and hydrophilic surfaces, as the proportion of ethane increases, the contact angle of the mixed droplet gradually increases. This is because ethane molecules added in mixed droplets act as a “glue” for methane molecules, weakening the movement of methane molecules, resulting in an increase in the contact angle.

关 键 词：烷烃液滴 润湿性 接触角 分子动力学 

分 类 号：O552[理学—热学与物质分子运动论]