Numerical investigation of influence of the temperature and relative humidity of air on the drying process of porous building

Abstract

The impact of the relative humidity and temperature of air on drying rates of the porous building material was investigated by the non-equilibrium heat and moisture transfer model implemented in the ANSYS Fluent software. Simulations of 24 hours drying process of a brick initially saturated in 97% by water were conducted for two drying air temperature, i.e., 23.8°C and 40°C and relative humidity in the range from 10% to 50%. The relative moisture content at the end of simulations and times needed to reach the relative moisture content bellow 0.3 were determined. Not only the temperature but also the relative humidity of drying air had impact on the drying rate during the first drying period when water evaporated from the sample surface. The temperature of drying medium was more important than the relative humidity during the second drying period when water evaporated inside the brick. The drying process was faster in the higher temperature than in the lower one, even for the high relative humidity.