Transp Porous Med (2013) 98:589–613
DOI 10.1007/s11242-013-0162-x
Identification of the Liquid and Vapour Transport
Parameters of an Ecological Building Material in Its
Early Stages
A. Zaknoune · P. Glouannec · P. Salagnac
Received: 20 July 2012 / Accepted: 17 April 2013 / Published online: 2 May 2013
© Springer Science+Business Media Dordrecht 2013
Abstract To fulfil the requirements of the new environmental standards in the building
sector, increased use of materials containing vegetable particles (hemp) is expected. The
manufacturing process of these materials has not yet reached the industrial stage which
requires control of the drying process. The objective of this work is to study the various
mechanisms of heat and mass transfers occurring during the drying of lime–hemp materials.
A macroscopic model has been developed and solved numerically. In order to obtain the
moisture transport coefficients, an optimization algorithm was used, allowing the estimation
of parameter values by minimising an error criterion between simulated and experimental
observations.
Keywords Heat and mass transfer · Porous media · Hemp material · Inverse techniques ·
Drying kinetics
List of Symbols
Variables
a
W
Water activity
C
p
Specific heat at constant pressure (J kg
-1
K
-1
)
D Diffusion coefficient (kg m
-1
s
-1
)
e Thickness (cm)
F
m
Mass flux (kg m
-2
s
-1
)
A. Zaknoune · P. Glouannec (B )
Laboratoire d’Ingénierie des MATériaux de Bretagne (LIMATB), Centre de Recherche,
Université de Bretagne Sud, B.P. 92116, 56321 Lorient Cedex, France
e-mail: patrick.glouannec@univ-ubs.fr
P. Salagnac
Laboratoire des Sciences de l’Ingénieur pour l’Environnement (LaSIE), Pôle Sciences et Technologie,
Université de La Rochelle, Av. M. Crépeau, 17042 La Rochelle Cedex 1, France
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