**Ultrasound Measuring of Porosity in Porous Materials** Ultrasound Measuring of Porosity in Porous Materials

DOI: 10.5772/intechopen.72696

Zine El Abiddine Fellah, Mohamed Fellah, Claude Depollier, Erick Ogam and Farid G. Mitri Zine El Abiddine Fellah, Mohamed Fellah,

Additional information is available at the end of the chapter Claude Depollier, Erick Ogam and Farid G. Mitri

http://dx.doi.org/10.5772/intechopen.72696 Additional information is available at the end of the chapter

#### Abstract

This chapter provides a temporal method for measuring the porosity and the tortuosity of air-saturated porous materials using experimental reflected waves. The direct problem of reflection and transmission of acoustic waves by a slab of porous material is studied. The equivalent fluid model has considered in which the acoustic wave propagates only in the pore-space. Since the acoustic damping in air-saturated porous materials is important, only the reflected waves by the first interface are taken into account, and the multiple reflections are neglected. The study of the sensitivity analysis shows that porosity is much more sensitive than tortuosity to reflection, especially when the incident angle is less than its critical value, at which the reflection coefficient vanishes. The inverse problem is solved using experimental data at a different incidence angle in reflection. Some advantages and perspectives of this method are discussed.

Keywords: porosity, tortuosity, porous material
