Coupled heat and mass transfer in building materials
Noumowe, A.N., T. Ohkubo, M. Makatayama, and K. Watanabe
1999 8th International Conference on Durability of Building Materials and Components, Vancouver, Canada, May 28 - June 3, pp. 932-942
Temperature, relative humidity, mortar, modelling, diffusivity
Noumowe, A.N., T. Ohkubo, M. Makatayama, and K. Watanabe, (1999), "Coupled heat and mass transfer in building materials", 8th International Conference on Durability of Building Materials and Components, Vancouver, Canada, May 28 - June 3, pp. 932-942.
Abstract:
This paper presents a part of numerical and experimental studies carried out in BRI of Japan on multi-layered structures subjected to variable climate conditions The initially quasi-saturated specimens of different mortar with different exposure sides were dried under the variable climate conditions. The environmental temperature, relative humidity and gross weight of each specimen were measured continuously. The distribution of the temperature, relative humidity, moisture content distribution of each specimen was calculated using a two dimensional heat and moisture simultaneous model and the gross weight evolution calculated from the obtained moisture distribution was compared with the measured one for each specimen. The physical properties of each component material necessary for calculation were obtained through experiments executed in BRI, JTCCM (Japan Testing Centre for Construction Materials) and CSTB in France. The numerical model was developed in BRI for prediction of heat and moisture transfer in multi-layered building components at hygroscopic conditions. The good agreement between calculation and measurement shows the applicability of the model to the quasi-saturated conditions.
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