Research on the Hygroscopicity of a Composite Hygroscopic Material and its Influence on Indoor Thermal and Humidity Environment

Abstract

Indoor air humidity is closely related to daily life and productivity. It is necessary to develop new materials which can maintain the indoor humidity environment steady within an acceptable range of 40–70%. In this paper a new composite hygroscopic material composed of wood fibre and sepiolite with expanded perlite (CHM-WSE) is used in a building envelope to evaluate its moisture buffering performance. A series of experiments assessing the microstructure, hygroscopicity, mechanical and thermodynamic properties of the new composite hygroscropic material have been executed. Furthermore, a numerical model for predicting the influence of humidity environment and energy consumption on composite hygroscopic mortar in different climatic regions has been established. The experiments show that the indoor moisture buffering performance in late spring is better than that in winter, when the practical moisture buffering performance can reach at 0.89 g/(m2%RH)@8/16h; and the non-uniformity coefficient of indoor relative humidity is about 0.006. The simulation results show that a room with CHM-WSE is more comfortable than a common mortar (CM) room, and it has better energy-saving performance in the hot summer and cold winter (HSCW) region in China. The experiments and simulations show that the developed hygroscopic material could be feasible for application in buildings.

Keywords

• composite hygroscopic material
• building envelope
• microstructure
• hygroscopicity
• multi-climatic region
• thermal and humidity environment