Molecular dynamics study of the slip properties of liquid lithium on α-Fe (100) surface

doi:10.7523/j.ucas.2024.047

Abstract

Abstract: Liquid lithium (Li) has a wide range of applications in nuclear fusion test devices, but the slip characteristics of liquid Li on the surface of solid materials have not been fully studied. In this paper, the Couette flow of liquid Li in α-iron (Fe) nanochannels was simulated by molecular dynamics method, and the effect of triangular surface roughness units on the slip characteristics of liquid Li on the surface slip characteristics of α-Fe (100) was analyzed. The results show that the influence of the angle on both sides of the triangle on the slip length is not significant, but there is a critical angle, when the angle on both sides of the triangle exceeds the critical value, the liquid Li will form a microscale vortex on the front side of the triangle, which significantly increases the flow resistance, and then causes a sudden and large decrease in the slip length, the critical angle and height are on a downward trend.

Key words: molecular dynamics, liquid lithium, Couette flow, slip length

CLC Number:

QU Huaiyuan, YU Xingang. Molecular dynamics study of the slip properties of liquid lithium on α-Fe (100) surface[J]. Journal of University of Chinese Academy of Sciences, DOI: 10.7523/j.ucas.2024.047.

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