论文标题
超冷的液体固定界面处的巨型滑动长度
Giant slip length at a supercooled liquid-solid interface
论文作者
论文摘要
在过去的二十年中,无论是在数值还是实验上,温度对液体固体界面上摩擦和滑移的影响都引起了人们的注意。但是,温度在接近玻璃过渡的滑移中的作用越来越少。在这里,我们使用分子动力学来模拟双分散原子流体,该原子流体可以保持在其熔点(超冷状态)以下的液体,以研究温度对液体和光滑的酸环壁之间的摩擦和在广泛温度下的摩擦长度的影响。在高温下,Arrhenius法律非常适合粘度,摩擦和滑动长度的温度依赖性。相反,当液体被过冷时,粘度会变成超级Arrhenian,而界面摩擦可以保持Arrhenian,甚至在降低温度时会大大降低,从而导致滑动长度的大量增加。我们通过流体的表面结晶以及流体界面层和壁的结构之间的不可通信性来合理化观察到的高素质。这项研究要求对低表面能固体上过冷液体的滑动长度进行实验研究。
The effect of temperature on friction and slip at the liquid-solid interface has attracted attention over the last twenty years, both numerically and experimentally. However, the role of temperature on slip close to the glass transition has been less explored. Here, we use molecular dynamics to simulate a bi-disperse atomic fluid, which can remain liquid below its melting point (supercooled state), to study the effect of temperature on friction and slip length between the liquid and a smooth apolar wall, in a broad range of temperatures. At high temperatures, an Arrhenius law fits well the temperature dependence of viscosity, friction and slip length. In contrast, when the fluid is supercooled, the viscosity becomes super-Arrhenian, while interfacial friction can remain Arrhenian or even drastically decrease when lowering the temperature, resulting in a massive increase of the slip length. We rationalize the observed superlubricity by the surface crystallization of the fluid, and the incommensurability between the structures of the fluid interfacial layer and of the wall. This study calls for experimental investigation of the slip length of supercooled liquids on low surface energy solids.