BSTRACT: Adapting to local climate is the nature of building. It has great potential to adjust indoor thermal environment by coupling passive solar heating, natural ventilation, and building thermal mass in Northwest China. The possible path is to improve building’s thermal stability by integrating PCM. The key point is to simulate building thermal environment with variable physical materials. In present study, heat capacity method, 1-D dimensional finite difference method and successive over-relaxation iteration were adopted. Adaptive mesh generation and optimization of thermal conductivity calculation on interface were conducted. The results agree well with analytical and experimental verification. It has been applicated in demonstration projects.

climate adaptability, building envelope, Western China, phase change material, demonstration projects.