Improving the thermal performance of the transparent building envelope: finite element analysis of possible techniques to reduce the U-value of the glassblocks

摘要

U-value of glazed elements is often a critical issue because these components, due to theirudsmall thickness and to the poor resistance of the glass and frame materials, cause veryudrelevant heat fluxes. This paper presents an investigation on the thermal properties of audparticular glazed component: the glassblock. Generally standard glassblocks have high U-udvalues in comparison to the maximum values allowed by energy efficiency standards forudglazed surfaces. This paper reports a summary of possible solutions that could improve theudperformances of the glassblock. A set of new configurations of the glassblock has beenuddefined by schematic models and their overall thermal resistance has been assessed by theudmeans of Finite Element software. The resulting performances are presented in terms of theudglobal thermal transmittance of the modified glassblocks, also considering the effects ofudsealing and mortar. The paper also shows some significant potential improvements to addressudnew production lines.