Studies on Natural Convection in Corrugated Slots

An analysis of natural convection in a horizontal slot formed by grooved isothermal plates has been carried out using a combination of theoretical and experimental approaches. The analysis in the case of a single grooved plate was focused on the transition to secondary states. It was demonstrated that primary convection occurs regardless of the temperature difference between the plates, with the fluid motion in the form of counterrotating rolls whose wavenumbers are dictated by the groove wavenumber. An increase in heating may lead to continuous system adjustments or an abrupt transition to a secondary state whose form depends on the groove characteristics and involves various wavenumber lock-ins between the groove and roll wavenumbers. The analysis of two grooved plates focused on primary convection and the effects of the relative positions of the two groove patterns. Multiple possible states have been identified in the case of a near-converging-diverging slot where the system exhibits hysteresis, limit points, and distinct solutions not associated with bifurcation branches.