Effects of Exterior Sun Shades on Heat Transfer by Solar Radiation

Abstract:

Heat transfer in walls, as affected by climatic conditions such as fluctuations in outside air temperature, solar radiation intensity and wind speed as well as wall structures and heat transfer coefficients of materials, becomes a complex and non-steady state. The aim of this paper is to examine the relationship between total whole-day solar radiation and heat absorbed by and released from materials. An reduced scale of experiment was conducted using reduced scale precast concrete slabs and focusing on the effect of heat transfer involving solar radiation, building materials and shading rate. The results show that even though the sun shadings would stem partly the solar radiation into the wall, yet they obstruct in the mean time the release of the heat, which absorbed hours ago. That leads to a temperature raise and uncomfort to the interiors.

• Periodical: Advanced Materials Research (Volume 935)
• Pages: 61-65
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.935.61
• Online since: May 2014
• Authors: Chih Hong Huang*, Shin Yu Tsai
• Keywords: Building Exteriors, Heat Flux Density, Heat Flux Temperature, Shading Effect, Solar Radiation, Unstable Heat Transfer

References

[1] Ma Chengwei, Bo Yunlong, Method for Calculation of Heat Release at Night and Evaluation for Performance of Heat Preservation of Wall in Solar Greenhouse, journal if shanghal jiaotong universuty 26(2008).

[2] Eduardo Krügera, Baruch Givonib, Thermal monitoring and indoor temperature predictions in a passive solar building in an arid environment, Building and Environment, 43(2008)1792-1804.

DOI: 10.1016/j.buildenv.2007.10.019

[3] Maria La Gennusaa, A model for managing and evaluating solar radiation for indoor thermal comfort, Solar Energy, 81(2007)594-606.

DOI: 10.1016/j.solener.2006.09.005

[4] ĝOliveti, Experimental investigation on thermal radiation exchange of horizontal outdoor surfaces, Building and Environment, 38(2003)83-89.

DOI: 10.1016/s0360-1323(02)00010-0

[5] Sami A. Al-Sanea, Thermal performance of building roof elements, Building and Environment. 37(2002)665-675.

DOI: 10.1016/s0360-1323(01)00077-4

[6] Liu Wenyan, Gengyao Ming, Concrete surface solar radiation absorption rate Experimental Research, China concrete and cement products, 4(2004).

[7] Giuseppe Oliveti, Natale Arcuri, Marilena De Simone, Experimental evaluations of the building shell radiant exchange in clear sky conditions, Solar Energy, 86(2012)1785-1795.

DOI: 10.1016/j.solener.2012.03.009

[8] Jian Yao, Chengwen Yan, Effects of Solar Absorption Coefficient of External Wall on Building Energy Consumption, World Academy of Science, Engineering and Technology, 52(2011).