Natural convection in central microcavities of vertical, finned enclosures of very high aspect ratios

Natural convection in the central microcavities of vertical, finned cavities of very high aspect ratios were numerically investigated using a spacewise periodical approach. When equally spaced fins are located on both active walls (problem b ), different circulation rates are found in two consecutive microcavities. The average Nusselt number in a region comprising two consecutive microcavities is higher than the one observed when the fins are attached to only one of the active walls (problem a ). The dependence of microcavity circulation rates and heat transfer on Rayleigh number, dimensionless fin length, and microcavity aspect ratio is discussed. The limits of applicability of the spacewise periodical approach are also outlined.