Moisture Effective Diffusivity in Porous Media with Different Physical Properties


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In the drying of porous media, the mass transport occurs in the pores as well as on the surface of the solid. The mechanisms involved can take place simultaneously, influenced by the predominant one and can change depending on the moisture content. In this work, the moisture effective diffusivity was estimated in solids with distinct structural properties in order to verify the predominant mechanisms according to the moisture content, analyzing the influence of the physical properties. The materials studied were NaY Zeolite, Kaolin, Silica and Alumina. The results of diffusion coefficient present a minimum at low moisture content that can be related to pore size.



Defect and Diffusion Forum (Volumes 258-260)

Edited by:

Prof. Andreas Öchsner and José Grácio




M. M.N.N. and M.A. Silva, "Moisture Effective Diffusivity in Porous Media with Different Physical Properties", Defect and Diffusion Forum, Vols. 258-260, pp. 207-212, 2006

Online since:

October 2006




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