Dynamic Modelling Of The Indoor Thermal And Humidity Environment In The Adobe Buildings

Chinese traditional residential building is a unique wealth in the course of human construction development. Research on the ecological experiences of Chinese traditional residential building can give a good deal of enlightment on the modem sustainable architecture practice.This thesis has studied systematically the indoor thermal and humidity environment in the adobe buildings in the Shangzhou area in Shaaxi province of China. This work is part of the project of the national distinguished youth project, scientifically refining the ecological experiences in the Chinese traditional residential buildings, which is financed by NNSF.In accordance to comprehensive analysis of the transient heat and mass transfer through the adobe building enclosure in the hygroscopic range, it is first to draw up the combined thermal and moisture transfer differential equations through wall-made-of-rammed-soil. Using the air humidity ratio and temperature as the driving potential used in this model are to avoid the discontinuous at the boundary with the ambient air as well as the boundaries with other materials. This proposed model is easy to use and the required parameters in the proposed model are normally available in the literature, and also the simulation results of this model are more accurate compared with the previous comprehensive models and the simplified vapour diffusion models.The dynamic effect of moisture absorption and desorption by interior matenals has been studied. The formula of the amount of moisture absorption and desorption by interior materials is given by using the air humidity as the potential difference. This formula is applicable for the engineering calculations, which will lead to increasing interests for engineers to consider the moisture problems in buildings because of the simplicity of the calculations. The existing methods of evaluating the surface mass transfer coefficient have been reviewed. Lewis relationship has been suggested to evaluate the surface mass transfer coefficient using the average surface convective transfer coefficient. In addition, a practical analytic technique for testing the surface mass transfer coefficient is proposed and the values of he surface mass transfer coefficient have been given for the particular desorption and absorption test and validated against Lewis relationship results.Indoor temperature and humidity evaluation equations of adobe buildings considering the moisture absorption and desorption by interior materials have been proposed based on the analysis of the indoor dynamic thermal and moisture process. The calculation program using the Matlab has been worked out to get the numerical solutions of the proposed models.The experiment has first been conducted in the laboratory to get the fundamentals thermal and moisture properties (such as materials density, specific heat capacity and thermal conductivity) and also the material moisture absorption isotherms of adobe building materials. The methods of measuring the surface mass transfer coefficient and material moisture content have been proposed. The material moisture content measurement method is based on measuring the variation of electrical resistance. Until now, no literature has been found to report the similar expenmental work in the world.Summer and winter field experiments have been carried out in the case adobe buildings during the last two yeais. The expenmental results show quatitively the dynamic behavior of indoor environment of adobe buildings. Computer simulations using the written-by-aurhor program have been executed with boundary conditions corresponding to the natural climate. Comparisons with experimental results and numencal solutions show good agreement with the proposed models. The validity of the simulation methods is verified The simulation results also show clearly the dynamic thermal and moisture adjusting effect by interior materials of adobe buildings. This research may be the fundamental work on how to improve the indoor environment in the Chinese traditional residen...