气泡与Janus固体表面间液膜薄化破裂机理研究

单个气泡与固体表面在溶液中的相互作用是矿物浮选、智能表面开发、潜航器减阻等领域的关键环节之一，其中液膜薄化破裂动力学是气泡与固体表面相互作用的核心。目前的研究主要集中在单个气泡与简单均相表面间的液膜薄化破裂动力学，但实际应用中的表面多为非均相表面，存在表面性质的不对称性，而这些不对称性对液膜薄化破裂动力学的影响机制尚不清楚。本项目拟通过实验和计算，对单个气泡与Janus固体表面在溶液中相互作用时的液膜薄化破裂动力学展开研究。利用Janus固体表面的不对称性模拟固体表面的非均相性，构建不对称疏水性和表面粗糙度可控的实验体系；通过实验观测气泡与Janus固体表面间的液膜薄化破裂过程，理清上述两种不对称性对液膜形状、液膜排液速度和液膜稳定性的单独和协同影响规律；建立理论模型并结合实验结果阐明固体表面不对称性对液膜薄化破裂动力学的影响机制。研究结果将为水下气体相关的前沿技术领域提供理论依据。

The interaction between an air bubble and a solid surface is of great importance to many daily life and industrial processes, such as mineral flotation, development of underwater smart surface and drag reduction of underwater craft. Thin liquid film drainage is the fundamental structural element of the interaction between an air bubble and a solid surface that has been attracted scientific interest. Currently, most studies are limited to characterize the thin liquid film drainage between an air bubble and a solid surface with homogenous property. However, the solid surfaces in practical applications are usually heterogeneous, which may lead to asymmetric interaction that has not been investigated yet. Therefore, in this project, we propose to study the thin liquid film drainage between an air bubble and a Janus surface experimentally and theoretically. The surface heterogeneity will be simulated by the asymmetric hydrophobicity or (and) surface roughness of the Janus surface. The evolution of film profile between the air bubble and the Janus surface will be captured by interferometry. By comparing the experimental film profile with the prediction from the new established model, the effect of asymmetric surface hydrophobicity and roughness on the film profile, flow rate and film stability will be revealed. These results will shed light on the interaction between an air bubble and a solid surface with asymmetric surface properties in liquids, which will be beneficial for many practical applications.