Experimental and Computational Tests Involving R-11,R-19 and R-30 Fiberglass Insulations

Abstract

The attic regions of residential dwellings are important areas with respect to energy conservation. The primary objective of this study is to determine the effective changes in total heat transfer due both to varying the attic insulation thickness from R-11 to R-19 to R-30, and to adding horizontally installed radiant barriers (for R-30). Experimental data (including winter and summer) were collected at an occupied north Mississippi residence, and various profiles such as time histories of temperature, heat flux, and vapor water concentrations are presented to support the experimentally determined effects on the overall heat transfer. A transient, one- dimensional, computational thermal model that incorporates combined conduction and radiation heat transfer and moisture transport is also used to predict the changes in the total heat flux. These predictions are then compared with the experimental results for typical summer and winter days for north Mississippi.

Keywords

heat-flux adsorption/desorption concentration-gradient compu tational model radiant barrier conduction radiation mass transport.

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