Porous medium

Many natural substances such as rocks and soil (e.g. aquifers, petroleum reservoirs), zeolites, biological tissues (e.g. bones, wood, cork), and man made materials such as cements and ceramics can be considered as porous media.

[4] The macroscopic technique makes use of bulk properties that have been averaged at scales far bigger than pore size.

It is obvious that the microscopic description is required to comprehend surface phenomena like the adsorption of macromolecules from polymer solutions and the blocking of pores, whereas the macroscopic approach is frequently quite sufficient for process design where fluid flow, heat, and mass transfer are of highest concern.

[4][6] Fluid flow through porous media is a subject of common interest and has emerged a separate field of study.

The study of more general behaviour of porous media involving deformation of the solid frame is called poromechanics.

The theory of porous flows has applications in inkjet printing[7] and nuclear waste disposal[8] technologies, among others.

[10] A representation of the void phase that exists inside porous materials using a set or network of pores.

They can be broadly divided into three categories: Porous materials often have a fractal-like structure, having a pore surface area that seems to grow indefinitely when viewed with progressively increasing resolution.

[13] Experimental methods for the investigation of pore structures include confocal microscopy[14] and x-ray tomography.

[15] Porous materials have found some applications in many engineering fields including automotive sectors.