Permeability, tortuosity, and attenuation of waves in porous materials
Journal Title: Civil and Environmental Engineering Reports - Year 2010, Vol 1, Issue 5
Abstract
The paper contains a consistent presentation of the construction of a linear poroelastic model and its applications in the theory of acoustic waves. The main purpose of this presentation is the discussion of material parameters describing the diffusion. This concerns particularly the permeability and tortuosity. In Section 2 we mention a few examples of porous systems in which diffusion processes play an important role. Section 3 contains a concise description of the two-component model describing saturated porous materials with diffusion. We point out the main features of such a system with the special emphasis of relative motion of components and changes of porosity. As a special case the governing equations of Biot’s model are presented. In Section 4 we discuss the notions of permeability, hydraulic conductivity and tortuosity. In particular the notion of the tortuosity tensor is introduced. Section 5 is the primer of the nuclear magnetic resonance method of experimental determination of permeability and tortuosity in various porous materials. Finally, Section 6 contains some issues concerning the propagation of monochromatic waves and, in particular, an influence of tortuosity on speeds and attenuation<br/><br/>
Authors and Affiliations
K. Wilmański
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