Effect of Porous Wettability on the Bubble Penetrability and Gas-Liquid Separation Character

To micro-structures of porous materials, the capillary force which is deeply affected by wettability plays an important role. In this paper, directly oxidation method and functionalization by trichloro (1H, 1H, 2H, 2H-perfluorooctyl) - silane are used to modify metal mesh wettability and superhydrophilic and superhydrophobic copper meshes are fabricated. Super-hydrophilic mesh can block bubbles from flowing through, while the superhydrophobic mesh can hold a column of liquid by counteracting gravity which is defined as a self-compatibility of meshes in this paper. As reported in the previous studies, the mesh with micro-pores can modulate two phase flow pattern to enhance heat transfer. In the present study, the dynamic principle of bubbles as they flow through meshes with different wettabilities is studied. A mathematical model between the critical diameter and flow conditions is developed. A fundamental conclusion for the modulation theory of two phase flow in porous structures can be reached.