运动速度与边界滑移相关性试验

Experimental Research on the Dependence Between Velocity and Boundary Slip

利用改进的原子力显微镜,针对微纳米间隙下固液界面的边界滑移现象进行了试验研究,重点考察了两固体表面的相对运动速度与边界滑移的关系.固体壁面样品采用亲疏水性不同的S i(100)表面和十八烷基三氯硅烷(OTS)自组装膜表面,试验液体采用去离子水.结果表明,两种表面与去离子水作用均会产生边界滑移,而且在试验进行的39~156μm/s的相对趋近速度下,无论表面的浸润性质如何,滑移长度均随着运动速度升高而升高,显示了边界滑移与运动速度的相关性.

Experimental research on boundary slip on micro/nano scale was investigated in this paper,which focuses on the relationship between velocity of two approaching solid surfaces and boundary slip using modified atomic force microscopy(AFM).Solid surface specimen was prepared as hydrophilic Si(100) and hydrophobic octadecyl trichloro silane(OTS) film surfaces verse deionized water.Results indicate that boundary slip occurs both on hydrophilic and hydrophobic surfaces.Furthermore,the degree of slip increases with the increase of velocity for the two surfaces when the velocity is between 39—156 μm/s,which shows that boundary slip is velocity dependent.The results are important for the research and control of the flow properties of confined liquids.