In the first part, the talk will focus on capillary rise mechanisms in heterogeneous porous material with different capillary sizes. Both theoretical and experimental work are performed to investigate the time evolution and the exchange at the interface of different porous media. It contains the homogeneous capillary (without layer exchange), which is presented to distinguish the different characteristic times and the liquid capillary rise regimes. Considering gravity effect, shear stress and inertia, three regimes are distinguished theoretically and experimentally based on these two dimensionless parameters (Bo and Ga). Theoretical analysis and simulation results show the capillary rise in tendency and the appearance of oscillatory phenomenon. The heterogeneous porous media are also investigated. A multilayer domain is adopted to model the multiple distribution in capillary sizes. The interaction between these layers (different equivalent capillary sizes) demonstrate how the cooperation appears in nature so as to fit with the optimal situation of fast filling the porous media or the equivalent in drying. Experimental results on both homogeneous and heterogenous cases have a favorable effect on the imbibition enhancement. In the second part, the talk will complete with the local and global evaporation in such complex porous media.

 This event is supported by the Polish National Agency for Academic Exchange,  grant no. BPI/STE/2021/1/00034/U/00001

All Warsaw-4-Phd students (and others) very welcome!