Macroscopic and Мicroscopic Simulation of Processes of the Interaction of Water Vapor and Slit-like Pores

Abstract—

So-called slit-like pores are one of the types of pores often encountered in natural and artificial construction materials. The complexity of studying processes of the interaction between a gaseous substance, in particular, water vapor, and a slit-like pore is related to the complex relief of pore walls and the nonuniform distribution of the main thermodynamic characteristics of water vapor along the pore length. In this context, a combined approach to describing the processes of interaction between slit-like pores and water vapor is formulated in this paper. This approach is based on the joint use of macroscopic diffusion and molecular-dynamic models. If the complexity of the pore wall geometry is taken into account, equations of the macroscopic diffusion model can be solved numerically; to do this, a table of the spatial distribution of diffusion-coefficient values obtained using molecular dynamic simulation is applied. This approach makes it possible to obtain a more exact solution to the equations of the macroscopic diffusion model, and, accordingly, enhance the accuracy of simulation of the processes of interaction between a slit-like pore and water vapor.