Determination of convective, radiative, and total heat transfer characteristics overa radiant heated ceiling: a computational approach
1Department of Mechanical Engineering, Yildiz Technical University, Istanbul, Turkey
J Ther Eng 2019; 5(5): 372-384
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Abstract

In the present study, a computational investigation is carried out within a model room of which dimensions has also been given in international standards for experimental approaches. In accordance with the experimental standards, the analyses are realized at the room dim ensions of (L x H x W= 4 x 3 x 4 m), and at the thermal boundary conditions of (T c = 35 50 o C), (T w = 15 24 o C), (T f = 15 24 o C). As a result of iterations conducted using a computational fluid dynamics package program code, each corresponding to a case study, convective, radiative, and total heat fluxes from radiant heated ceiling are obtained, and afterward using relevant reference temperature proposed in the literature, heat transfer coefficients pertaining to convection, radiation, and total heat tran sfer have been found.
In conclusion, average heat flux values of 95.83 Wm 2 and 17.49 Wm 2 are gained through the examined radiant heated
ceiling, by means of radiation and convection, respectively. This denotes that roughly 85% of total heat transfer from
the ceiling arises through radiation that is very compatible with the relevant literature. Finally, spanning the entire different case studies, average convective, radiative, and total heat transfer coefficients of 1.1 Wm 2 K 1 , 5.4 Wm 2 K 1 , 7.6 Wm 2 K 1 ar e acquired.