DETERMINATION OF CONVECTIVE, RADIATIVE, AND TOTAL HEAT TRANSFER CHARACTERISTICS OVER A RADIANT HEATED CEILING: A COMPUTATIONAL APPROACH

Year 2019, Volume: 5 Issue: 5, 372 - 384, 22.09.2019

Özgen Açıkgöz

https://doi.org/10.18186/thermal.623191

Cited By: 4

Abstract

also been given in international standards for experimental
approaches. In accordance with the experimental standards, the analyses are
realized at the room dimensions of (L x H x W= 4 x 3 x 4 m), and at the thermal
boundary conditions of (T_c= 35 – 50^oC), (T_w=
15 – 24^oC), (T_f= 15 – 24^oC). 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 transfer 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^-2K^-1,
5.4 Wm^-2K^-1, 7.6 Wm^-2K^-1 are
acquired.

Keywords

Ceiling Heating, CFD, Radiation, Convection

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