Effects of condensation and liquid transport on the thermal performance of fibrous insulations

Abstract

The moisture gain by a fibrous insulation slab from a humid ambient is simulated under laboratory conditions. The liquid distribution, the total moisture gain, the heat flux and the temperature distribution are measured for a range of experimental conditions. The testing times ranged from 300 to 600 h. The physical processes involved in liquid transport are identified. Initially the total moisture gain increases nearly linearly with time and then decreases gradually. The heat flux shows a very gradual increase with time. The semi-empirical model used gives reasonable predictions of some of the measured quantities.