Evaporation in porous media

It has been shown that the ILG model can adequately simulate well-established macroscopic flow regimes, like Poiseuille s law (Di Pietro et al., 1994). The ILG model was also applied to study evaporation in porous media (Pot, 1994), infiltration in two-dimensional saturated and non-saturated porous media with macropores (Di Pietro, 1996) and water storage in roughed infiltrating and non-infiltrating surfaces (Garcia Sanchez et al., 1996). 

A One-Dimensional Analysis for Bo 1. Figure 9.22 depicts the one-dimensional model for evaporation in porous media with heat addition q from the impermeable lower bounding surface maintained at T0> Ts, where T, is the saturation temperature. The vapor-film region has a thickness 8g, and the two-phase region has a length 8g(. 

The motion of water is influenced by the water pressure, which is induced by the capillary or osmotic suction resulting from evaporation in porous media. The water flows iu the relatively larger pores saturated with water rather than by diffusion process. In such a case, the pressure diffusion term dominates the mass-transfer rate in Equation 35.6. The Soret effect described by the tanperature diffusion term is generally considered small compared with other terms. Then Equation 35.6 can be simpUlied as... 

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