A
mathematical model describing coupled heat,
moisture and salt transport in
porous materials is presented. Salt
dissolved in water can be transported due
to various mechanisms: dispersion caused by the salt concentration
gradient,
and advection resulting from the capillary pressure gradient. The influence of
a salt on physical properties of water such as: water density and water dynamic
viscosity is also
considered. The water sorption isotherms are modified to take
into account both osmosis and effects of the salt presence on the surface
tension and contact angle. Salt precipitation in the state of a thermodynamic
balance between dissolved and crystallized salt is also considered. Finally,
the software was also developed and an example of wall drying process was
numerically solved.