Considers the coupled problem of heat and vapour diffusion within porous fibre glass insulation materials, under transient conditions of heat conduction and water vapour adsorption/desorption, condensation and frosting. Describes a special laboratory test facility for measuring transient, one-dimensional temperature, heat flux and moisture accumulation for a range of cold plate temperatures near 10degC (50degF) down to minus 20degC (minus 4degF) and warm- side relative humidities from 35% to 90%. Uses the measured boundary conditions as input conditions for a numerical model for heat and water vapour diffusion. Finds the simulation results compared well with measured data within the experimental uncertainty for all the results except heat flux when the insulation slab was subjected to repeated temperature cycles. Also includes results for a cyclic cold temperature case.

KEYWORDS: year 1996, Heat flow, fluid flow, moisture, thermal insulation, glass fibre, experiment, laboratory testing