Abstract:
The movement of the fluid in natural convection results from the buoyancy forces imposed on the fluid when its density in the proximity of the heat transfer surface is decreased as a result of the heating process. In this work, computational study of the flow initiated by natural convection was done. A numerical study was performed on a rectangular enclosure with varying aspect ratio to predict streamlines and isotherms distributions of a 2-D buoyancy driven turbulent flow. The RANS, energy and turbulent transport equations with Boussinesq approximations were discretized using Finite Difference method. The low Reynolds k-epsilon (𝜅−𝜖) model, Aspect ratio of 2,4,6 and 8 and Prandtl number 0.71 and at a constant Rayleigh numbers (Ra) were used and governing equations were solved. The results of isotherms and streamlines had been represented. Based on the numerical results, as the aspect ratio increased, the flow becomes less turbulent.
