Viscous stabilization of drying front: Three-dimensional pore network simulations

In this study, a recently developed pore network drying model [Metzger, T., Irawan, A. and Tsotsas, E., 2007, Isothermal drying of pore networks: influence of friction for different pore structures, Dry Technol, 25: 49–57], which accounts for liquid viscosity, is applied to three dimensions for the first time. Isothermal convective drying is simulated for a cubic network (25 × 25 × 50) with pore throats with a narrow radius distribution. The role of liquid viscosity is assessed by comparison with non-viscous drying of the same network. Simulation results are presented as phase distributions, saturation profiles and drying rate curves. In the viscous case, a stabilization of the drying front is observed. However, as the network dries out from the surface, the finite drying front gradually widens up and does not approach an asymptotic limit.