NUMERICAL SIMULATION OF FLOW THROUGH ABSORBING POROUS MEDIA: PART 2. SWELLING POROUS MEDIA

In the first part of this two-paper series, published in the Journal of Porous Media in 2021, a novel framework based on the combination of finite volume method and volume of fluid method was proposed to model the flow through absorbing porous media under rigid conditions. The results from the model showed a promising correlation with the experimental and analytical predictions for the wicking height and radius. However, the framework did not include swelling porous media conditions. The swelling effect influences the porosity and permeability of the porous medium considerably, therefore causing errors in the flow front location predictions if the effects are not taken into account in the numerical models. Here, the framework is extended by including the swelling effects. The empirical relation for changes in permeability is included in the existing methodology to include the swelling effects. The predictions from the proposed model showed excellent agreement with the experimental data. The modeling approach is further extended to model the flow through single and multiple layer diaper geometries. The results showed notable patterns of liquid–air interface, demonstrating the ability of the present method to track the flow fronts in combined wicking and draining flow scenarios.