Thermal Performances of CLOHP in Attic Cooling with Flat Metal Sheet Roof

Nopparat Seehawong, Ninnart Rachapradit, Piyanun Charoensawan

Abstract


This research developed a prototype of a flat metal sheet roof utilizing a closed-loop oscillating heat pipe (CLOHP) to dissipate heat from the attic. The study will examine two roof designs: a bare roof and a roof with CLOHP that utilizes forced air-cooling using an exhaust fan. Additionally, the study will investigate the effects of solar intensity at 200, 400, and 600 W/m², using a solar simulator equipped with halogen lamps to replicate solar energy, on the system's performance. The findings indicate a direct correlation between solar intensity and the temperatures of the roof surfaces and attic for all tested configurations. Notably, the CLOHP-equipped roof demonstrated superior performance, achieving an attic temperature of 38 °C under the maximum solar intensity of 600 W/m² and a heat transfer rate of 66 W. These results correspond to significant reductions of 22% in temperature and 57% in heat transfer compared to the standard bare roof. Moreover, the developed roof system is easy to construct, user-friendly, and requires negligible maintenance.

Keywords


attic; closed-loop oscillating heat pipe; flat metal sheet roof; thermal performances

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References


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DOI: https://doi.org/10.64289/iej.25.03A11.8790138