Asymptotic solution of natural convection problem in a square cavity heated from below

Studies a two‐dimensional natural convection in a porous, square cavity using a regular asymptotic development in powers of the Rayleigh number. Carries the approximation through to the 34th order. Analyses convergence of the resulting series for the Nusselt number in both monocellular and multicellular cases, providing insight in the validity regions of the power series.