Fluids and Rocks - Introduction to Carbon Capture and Sequestration - page 401

We see that the contact angle, and hence the wetting behavior, not
only depends on the interactions of the fl uid with the substrate (i.e.,

γ LS )
but also on the liquid-gas surface tension. Let us now look at two model
pores. Our models are cylindrical pores, one with a large diameter and
one with a small one. Figure 9.4.3 shows one pore (left) in contact with
a gas that wets the substrate and one (right) with a gas that does not wet
the walls of the pores. We see that in the fi rst case a wetting layer covers

Figure 9.4.2 Partial wetting
Partial wetting of a liquid droplet on a substrate. θ is the contact angle and γ the inter-
facial tension between the solid (S), liquid (L), and gas (G) phase.

L 1

L 2

Figure 9.4.3 Capillary condensation
Porous media in contact with a wetting fl uid (left) and a non-wetting fl uid (right). The top
fi gures represent a large pore and the bottom ones a narrow pore.