Numerical simulation of evaporation from nanoporous arrays:

Coupled analysis of liquid phase and nonequilibrium gas flow

Abstract

The evaporation from nanoporous membranes is of great importance for understanding natural phenomena and industrial applications, such as transpiration, the evaporation from soil surfaces, and membrane-based cooling devices. A nonequilibrium gas flow near a liquid–vapor interphase, known as the Knudsen layer, plays a crucial role because the evaporative mass flux is determined within this layer. The 3D analysis of the heat transfer in vapor, liquid and solid phase is required because the porous pitch takes a value close to mean free path and the solid phase plays a role to transport the heat flux to the surface. To simulate gas flows we used the variance reduction method, which significantly reduces the computational cost for low Mach number flows. We built a coupled analysis method for liquid phase and nonequilibrium gas flow and evaluated the porous diameter dependence of the evaporative mass flux.