Limits of the Oberbeck-Boussinesq approximation in a tall differentially heated cavity filled with water

摘要

The present work assesses the limits of the Oberbeck-Boussinesq(OB)approximation for the resolution of turbulent fluid flow and heat transfer inside a tall differentially heated cavity of aspect ratio =6.67 filled with water(Pr=3.27, Rα= 2.12×10~(11)). The cavity models the integrated solar collector-storage element installed on an advanced facade. The implications of the Oberbeck-Boussinesq approximation is submitted to investigation by means of direct numerical simulations(DNS)carried out for a wide range of temperature differences. Non-Oberbeck-Boussinesq(NOB)effects are found to be relevant, especially beyond the temperature difference of 30℃, in the estimation of heat transfer, stratification, and flow configuration.