正十六烷基础油中减摩剂和分散剂相互作用的分子动力学模拟  

Molecular Dynamics Simulation of the Interactions Between Friction Modifier and Dispersant in N-hexadecane Base Oil

作　　者：余辉 潘伶[1,2] 林国斌 YU Hui;PAN Ling;LIN Guobin(School of Mechanical Engineering and Automation,Fuzhou University,Fuzhou Fujian 350108,China;Fuzhou Friction and Lubrication Industry Technology Innovation Center,Fuzhou Fujian 350108,China)

机构地区：[1]福州大学机械工程及自动化学院,福建福州350108 [2]福州市摩擦与润滑行业技术创新中心,福建福州350108

出　　处：《润滑与密封》2022年第1期67-75,共9页Lubrication Engineering

基　　金：国家自然科学基金项目(51875105,51875106);晋江市福大科教园区发展中心科研项目(2019-JJFDKY-54);福建省产学合作项目(2020H6025)。

摘　　要：采用分子动力学模拟加入减摩剂单油酸甘油酯(GMO)和分散剂聚异丁烯琥珀酰亚胺-多胺(PIBSA-PAM)的正十六烷基础油在不同压力条件下剪切时的摩擦学特性。构建光滑铁壁面的纳米间隙润滑剂模型,对GMO分子、PIBSA-PAM分子和壁面之间的吸附和团聚行为进行阐释,得出润滑油膜中每种分子的密度分布及剪切过程中的速度分布,输出固体壁面的横向力和正压力后计算得到摩擦因数。结果表明:在不同压力下加压至稳定时,GMO与PIBSA-PAM的近壁面密度峰值与正十六烷的近壁面密度峰值所处位置均相同,表明GMO、PIBSA-PAM和正十六烷的壁面吸附存在竞争关系;在不同压力下剪切时,GMO倾向于吸附在壁面,而PIBSA-PAM倾向于分散于基础油中;GMO质量分数为5.0%左右时,正十六烷基础油摩擦因数最小,为0.067。Molecular dynamics simulation was used to study the frictional properties of N-hexadecane base oil added Monooleate Glyceride(GMO)and Polyisobutylsuccinimide-Polyamine(PIBSA-PAM)under shearing at different pressures.The nanogap lubricant model of smooth iron wall was constructed,and the adsorption and self-assembly behaviors of GMO,PIBSA-PAM and the wall surface were described.The density distribution of each molecule and velocity distribution of the lubrication film during the shearing process were analyzed.The friction coefficient was obtained by the output of transverse force and positive force on the surface.The results show that when the lubrication system is compressed to the stable state under different pressures,the density peaks of GMO and PIBSA-PAM near the wall surface are the same as that of N-hexadecane,which indicates that there is competition of adsorption among GMO,PIBSA-PAM and N-hexadecane near the surface.When the lubricating system is sheared at different pressures,the GMO tends to adsorb on the surface,while PIBSA-PAM tends to disperse in the base oil.When the mass fraction of GMO is around 5.0%,N-hexadecane has the minimum friction coefficient of 0.067.

关 键 词：边界润滑 单油酸甘油酯 聚异丁烯琥珀酰亚胺-多胺 分子动力学 摩擦因数 

分 类 号：TH117.2[机械工程—机械设计及理论]