Heat exchange by convection and thermal conduction between the two environments of a building separated by a vertical wall and double wall air gap are studied numerically. The transfer is two- dimensional effect of the external environment the hottest to the internal environment of the building through a facade consisting of two walls separated by a layer of air. The structure of the flow and the temperature distribution in the two media and the temperature profile of the surfaces of the front wall are determined based on the simulation results for the temperature difference (Rayleigh number) and the temperature sinusoidal excitation
31 December 2016 in The International Journal of Multiphysics
This work presents a study by numerical simulation of mixed convection in a rectangular cavity with a sinusoidal temperature imposed on the right vertical wall while the other wall on the left is kept at a cold temperature. The upper and lower walls are thermally insulated, the inlet and outlet ports are respectively located on the hot wall to the bottom and on the top to the left. The enclosure represents a practical system such as an air-cooled electronic device, the heat source represents a radiator or an electronic component located in three different positions towards the left side at the bottom, the center and towards the right side at the top in such an enclosure. All calculations are made for a range of Richardson number from 0 to 10 and Reynolds numbers from 50 to 200. The influence of Richardson number, the position of the heat source and the influence of amplitude and phase deviation of the temperature imposed on the Nusselt number on the hot surface is studied. The results are presented in the form of streamlines and isotherms graphs as well as the variation in maximum temperature and mean Nusselt number under different conditions. The numerical resolution of the governing equations is obtained using the software of Multiphysics Comsol based on the finite element method.