Numerical study of natural convection phenomenon close to a cooling stage has been investigated in a two dimensionally controlled environment. The study was conducted for ambient air which was kept at constant temperature (22°C) and Prandtl number of this Newtonian fluid was taken as 0.71. The cooling stage was kept at 5°C and height of the stage was considered 0.02 m. The stage was located at the bottom on the computational domain. The center of cooling stage was placed at X = 0.35 m and X = 0.5 m respectively from the left boundary of the domain. Later, computational analysis was performed to solve coupled momentum and energy equations for appropriate boundary conditions. The study was performed for a range of Rayleigh number from 102 to 107. Thermal and hydrodynamic behavior was reported in terms of isotherms, streamlines and average Nusselt number calculation. The position of the stage significantly effects heat transfer and flow fields. Nusselt number was evaluated close to cooling stage. Streamlines resulted huge recirculation region which was symmetric about the vertical mid-centerline of the domain for cooling stage located at X = 0.5 m. The center of core vortices shifted near to the cooling stage as Rayleigh number increases ensuring enhancement of heat transfer. Additionally, increasing Rayleigh number induces significant buoyancy driven flow. The velocity of this driven flow increases towards left and right wall as Rayleigh number increases. Velocity profile was also evaluated due to flow inside the enclosure. A parabolic variation was observed for horizontal velocity component near the isothermal walls and it was found less significant compared to vertical component due to buoyancy driven flow. Moreover, the asymmetric distribution of isotherms created by eccentric position of the stage resulted better enhancement than centric position of the cooling stage. Finally, this results would help the researchers find the optimal position of any sample on a cooling stage subjected to convection phenomenon. This could be significant in the collection of experimental data for condensation and frost formation.

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