Paper Conference

Proceedings of SimBuild Conference 2012: 5th conference of IBPSA USA


Zonal Approach to Modeling Thermally Stratified Atria

Timothy C. Moore, Peter J. Ouzts
Integrated Environmental Solutions, Ltd., Glasgow, Scotland

Abstract: Thermally stratified atria and similar spaces present challenges for building thermal-comfort and energy modeling. This work tests a zonal modeling method for dynamic thermal and energy simulation of a heavily glazed and thermally stratified atrium cooled by displacement ventilation. The goal of the study was to explore the extent to which this method offers any improvement over simpler methods with respect to assessing thermal comfort and energy consumption. This paper describes a thermal and bulk-airflow zonal modeling strategy that appears to capture the some of the principal effects of thermal plumes generated when glazed facades and other interior surfaces are heated by solar radiation. This approach may be applicable to a relatively broad range of projects with similar characteristics. A CFD tool running the same model of the space, but without the zonal subdivisions, was used to tune the dynamic thermal/bulk-airflow model and to assess the degree to which the latter provides consistently appropriate results with variation in solar gain. The zonal approach appears to have some advantage with respect to predicting thermal comfort as a function of heat removed from the interior of glazed facades; however, a comparison with a simpler method that does not use bulk-airflow modeling suggests that this simpler method may provide much of the same benefit with respect to assessing energy consumption.
Pages: 168 - 176