中文摘要：

本文建立了粗糙固体表面上液滴铺展过程的理论模型并采用了格子Boltzmann方法进行数值模拟，研究了粗糙与光滑表面上液滴铺展过程的形貌变化。研究结果表明，无论表面光滑还是粗糙，液滴都沿着半径方向逐渐铺展，整体首先呈帽形，随着时间的推移，液滴在表面铺展成一平面。粗糙表面与光滑表面铺展特性间的差异主要在于粗糙表面液滴受到粗糙元干扰，其铺展形状随时间推移由圆形向八边形过渡。粗糙元间隙的增大导致液滴润湿半径增大，液滴厚度沿半径方向变化梯度降低。

英文摘要：

A theoretical model of droplet spreading on a rough solid surface is developed and numerically analyzed by lattice Boltzmann method （LBM） to investigate the variation of droplet morphology on rough and smooth surfaces. The results indicate that, no matter whether the surface is rough or smooth, the droplet spreads along the axial direction when the droplet is in contact with solid surface and initially deforms like a hat followed by a final lamella. The major difference of spreading characteristics between smooth and rough surfaces is that, the shape of droplet on a rough solid surface translate from the circle to octagon owning to the disturbance of roughness elements while the droplet shape is always circular on a smooth surface. In addition, increases in roughness spacing lead to a large wetting radius of droplet and hence result in a decreasing thickness gradient of lamella in the axial direction.