Interlayer and cavity contribution to creating high light-to-solar-gain-ratio glass block from waste glasses

Abstract

In order to save building energy consumption, glazing in warm humid climates is recommended to have high light-to-solar-gain ratio (LSG). LSG denotes the ratio of the visible light transmittance (VT) to its solar heat gain coefficient (SHGC). In laminated glazing LSG depends on the design of the cavity and (inter) layers. This study explores the contribution of the interlayers and cavity in creating high LSG glass block from laminated waste glasses. Analytical methods and computational simulations using the comparative method and heat balance model were employed to obtain a glass block model with the optimum combination of VT, SHGC and thermal transmittance (U). The cavity effect on the increasing VT is shown by simulation and laboratory test results. Based on SHGC laboratory test results, the presence of an interlayer decreases the simulated SHGC by 69–89%. The LSG for a laminated glass block with a certain number of closed cavities and interlayers can reach 4.35 times the calibrated laboratory LSG.

Keywords:

• cavity
• glass block
• interlayer
• light-to-solar-gain ratio

Acknowledgements

This research was supported by the Directorate General of Higher Education (Dirjen DIKTI), Ministry of National Education in the scheme of “National Research Competitive Grant” (Hibah Bersaing) under the contract no. 055/SP2H/PP/DP2M/IV/2009 on April 6, 2009 and no. 301/SP2H/P/DP2M/IV/2010 on April 12, 2010. Authors are also grateful to Mr. Widijanto (laboratory staff) for preparing the specimens.