Numerical Investigation of Free Convection Heat Transfer from Two-Dimensional Rectangular Enclosure with Discrete Isothermal Heating from Bottom Side

The thermal energy exchange by means of free convection between two sources of heat located
in an enclosure with a rectangular shape on the bottom side with sawtooth periodic (repetition)
upper wall has been studied numerically. The length of the two isothermal sources was about
20% of the total bottom surface length with a constant power. The impacts of the sawtooth
waves and the separation of both heat sources in the heat exchange were analyzed during the
numerical simulation. The working fluid was air with Prandtl number (0.72) and Rayleigh
numbers that varied from 103 to 105. The finite volume method with SIMPLE algorithm was
used to solve the governing partial differential equations (continuity, Navier Stokes and energy
equations) and to analyze the flow and temperature fields inside the enclosure. The simulated
data revealed that an increase in the distance between two heat sources results in a raise of the
mean Nusselt Number for all the ranges of Rayleigh Numbers studied, while an increase in the
sawtooth periodic results in a diminishing of the mean Nusselt Number for all the Rayleigh
Numbers analyzed.

Keywords:
natural convection, rectangular
enclosure, discrete heat sources, finite
volume method

https://doi.org/10.18280/ijht.370424

Dr.mohammed Ali Mahmood Hussien

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