Porous media are materials or structures that contain void spaces – the so-called “pores”. Almost all materials are porous, for example, the natural soil, the subsurface, paper, the human body etc. That's why we find porous media almost everywhere in our everyday life.
Fig 1: Porous structure*
These pores are filled with fluids. Fluids can be gases (e.g. air or Carbon dioxide) or liquids (e.g. water)
Fig 2: Gas in a porous medium* Fig 3: Liquid in aporous medium*
Fluids can flow through the pore space. Understanding how liquids or gases move in or through these structures helps in a range of fields from energy storage to climate prediction.
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* Abstract illustrations