论文标题
通过薄流体膜突出的软胶囊之间的毛细管相互作用
Capillary interactions between soft capsules protruding through thin fluid films
论文作者
论文摘要
当悬浮液干燥时,悬浮液蒸发,留下由悬浮颗粒组成的干膜。在干燥的最后阶段,底物上的流体膜的高度下降到粒径以下,从而诱导局部界面变形,从而导致颗粒之间的毛细血管相互作用很强。尽管对刚性颗粒之间的毛细血管相互作用进行了充分的研究,但在膜干燥的最后阶段,柔软颗粒的行为以及其柔软性的作用仍然可以理解很多。在这里,我们使用了我们最近引入的数值方法,该方法将使用晶格Boltzmann方法描述的流体融合到可变形物体的有限元描述中,以研究具有悬浮软颗粒的膜的干燥过程。我们测量的半月板变形和侧向毛细管在刚性颗粒的情况下与以前的理论和实验作品非常吻合,表明随着颗粒柔软度的增加,变形变得较小,导致较弱的横向相互作用力。在大的颗粒间距离处,力接近刚性颗粒的力。最后,我们研究了在膜干燥的后期粒子簇的时间依赖性形成。
When a suspension dries, the suspending fluid evaporates, leaving behind a dry film composed of the suspended particles. During the final stages of drying, the height of the fluid film on the substrate drops below the particle size, inducing local interface deformations that lead to strong capillary interactions among the particles. Although capillary interactions between rigid particles are well studied, much is still to be understood about the behaviour of soft particles and the role of their softness during the final stages of film drying. Here, we use our recently-introduced numerical method that couples a fluid described using the lattice Boltzmann approach to a finite element description of deformable objects to investigate the drying process of a film with suspended soft particles. Our measured menisci deformations and lateral capillary forces, which agree well with previous theoretical and experimental works in case of rigid particles, show the deformations become smaller with increasing particles softness, resulting in weaker lateral interaction forces. At large interparticle distances, the force approaches that of rigid particles. Finally, we investigate the time dependent formation of particle clusters at the late stages of the film drying.