Abstract: In this paper we presented the investigation of the moisture condensation of building envelop which was a core component of thermal design for buildings under humid and hot environment. Based on the heat-transfer principle composed of heat conduction and natural convection, the results of the internal wall temperature under different environment conditions were discussed. A judgement method of moisture condensation was proposed,and the effects of the temperature and humidity of the environment on the dewing characteristics of walls were investigated. The results reveal that the condensation never occurs in summer, but it always happens in winter when the relative humidity of the indoor environment is higher than the critical value. In order to prevent the condensation, we also suggested the critical values of insulation-layer thickness and relative humidity. Anti-condensation design of industrial plants could use the methods and results mentioned above as a reference.

Keywords: natural convection; heat transfer; dew point temperature; moisture condensation of walls

(Journal of China Institute of Water Resources and Hydropower Research, Vol. 16, No. 4, 2018)