The effects of radiant barriers on ceiling heat flux and energy usage
- Clemson Univ., SC (United States). Dept. of Mechanical Engineering
In this study a gable ventilation system was installed in an experimental facility to determine the effects of ventilation type on radiant barrier performance. The radiant barriers were installed horizontally above the ceiling insulation. The measured performance was then compared to documented results for a ridge and soffit ventilation system. This study experimentally determined the effects of radiant barriers on ceiling heat loss in cathedral ceiling homes during the winter heating season. A normalization procedure was used to allow short term, clear sky measurements from different days of similar weather to be used to determine radiant barrier performance. The procedure normalized for weather variations of ambient temperature and solar insolation under clear sky conditions to isolate the effects of radiant barriers. In these studies radiant barriers were examined for energy conservation, load shifting and demand reduction characteristics. A thermal model to predict shingle temperature in cathedral ceiling homes was also developed. The experimental results show that radiant barriers are not as effective in homes with a gable ventilation system as compared to homes with a ridge and soffit system. This result is primarily due to increased air flow rates with a ridge and soffit ventilation system. For the gable ventilation system the radiant barriers reduced the peak heat flux by 20% and provided an energy conservation of 4.1%. However, it was found that better load shifting characteristics were present. Radiant barriers conserved energy in a winter study of cathedral ceilings by actually reducing the total heat loss from the ceiling by 40% for peak heating days. The shingle temperature model was validated by comparing ceiling heat flux predictions using actual measured temperatures and modeled temperatures.
- OSTI ID:
- 455366
- Report Number(s):
- CONF-950828-; ISBN 0-7918-1712-1; TRN: IM9716%%215
- Resource Relation:
- Conference: 1995 National heat transfer conference, Portland, OR (United States), 5-9 Aug 1995; Other Information: PBD: 1995; Related Information: Is Part Of 1995 national heat transfer conference: Proceedings. Volume 11: Computational heat transfer in cryogenic applications; Frost formation and heat transfer in cold environments; Student session on design in heat transfer; HTD-Volume 313; Obasih, K.M.; Tao, Y.X.; Figliola, R.S. [eds.]; PB: 104 p.
- Country of Publication:
- United States
- Language:
- English
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