A simple Lennard-Jones fluid confined in a slit nanopore with hard walls is
studied on the basis of a multilayer structured model. Each layer is
homogeneous and parallel to the walls of the pore. The Helmholtz energy of this
system is constructed following van der Waals-like approximations, with the
advantage that the model geometry permits to obtain analytical expressions for
the integrals involved. Being the multilayer system in thermodynamic
equilibrium, a system of non-linear equations is obtained for the densities and
widths of the layers. A numerical solution of the equations gives the density
profile and the longitudinal pressures. The results are compared with Monte
Carlo simulations and with experimental data for Nitrogen, showing very good
agreement.Comment: 6 pages, 5 figures