The paper presents the experimental and simulation results of a study on simultaneous heat, air, and moisture transport in a loose-fill insulation. The study was aimed at investigating the thermal and moisture effects of natural air convection with no liquid transport present and to validate a numerical model. The vertical rectangular cavity of the structure was filled with preconditioned expanded polystyrene material. The structure was positioned between two climate chambers at different temperatures. The quasi-steady-state temperature distribution in the cavity and the transient moisture condition were measured. The material properties were also measured for use in numerical simulations. Both measurement and simulation results indicate that natural convection in a porous cavity not only increases heat flow through the structure but also significantly influences moisture redistribution within the structure. The model can predict the moisture distribution fairly well in a qualitative sense, and the heat flows quantitatively, in a good way.

Authors: Katrin Riesner; Jinkai Wang; Carl-Eric Hagentoft, Ph.D.; Georg-Wilhelm Mainka P.E., Dr.-Ing.
Citation: Thermal Performance of the Exterior Envelopes of Buildings VIII
Keywords: December, Florida, 2001