Numerical simulation of dynamical aspects of natural convection flow in a double-skin façade

A dynamical study of the flow in a double-skin façade was carried out numerically for modified Rayleigh numbers in a range corresponding to the boundary layer-type flow in the laminar regime. The façade is modeled by an asymmetrically heated vertical plane channel. 2D numerical simulations have been carried out with the finite volume approach. Velocity profiles show the asymmetric character of the flow. The presence of a recirculation zone at the channel outlet near the unheated wall has been highlighted. Numerical results are compared with experiments carried out in water. This simulation allows finding the patterns of the recirculation zone observed in the experiments. Numerically predicted recirculation lengths are overestimated by about 6% compared with the experimental results.

► In this study we examine the natural convection flow dynamics in a double-skin façade.
► 2D numerical simulations have been carried out with the finite volume approach.
► Investigations focus specifically on the influence of the aspect ratio and the modified Rayleigh number on the flow structure.
► Numerically predicted recirculation length is overestimated by only 6% compared with the experimental results.
► Axial velocities and recirculation length increase with the Rayleigh number.