Using the porous materials to guide and separate multi-phase flow became a leading edge topic. The mechanism is the force balance of three-phase interface

in which the wettability of substrate is the key factor. An adiabatic and visible experiment flat form was built to study the effect of wettability on the phase interface movement and the separation with a super-hydrophobic and a super-hydrophilic mesh. As the result

the super-hydrophobic and super-hydrophilic mesh showed the self-compatibility. With this ability the super-hydrophilic mesh can block bubbles from flowing through

while the super-hydrophobic mesh can hold a column of liquid by counteracting gravity. Base on the stagnant experiment the super-hydrophobic mesh with a contact angle of 151° showed a resistance of 117.6 N·m-2 to water

and the super-hydrophilic mesh (θ=0°) indicated a resistance of 49 N·m-2. During the two-phase flow experiment

the super-hydrophobic mesh showed an enhancement on separation of bubbles

while the super-hydrophilic mesh refused the penetration of bubbles with a layer of liquid film. A mathematic relation of self-compatibility of mesh and the critical diameter of separation was concluded. The modulation of wettability of porous mesh can promote the phases separating which will widen their applications on phase change heat transfer fields.