Research On The Thermal And Moisture Performance Of Cavity Wall In Hot Summer And Cold Winter Zone

With growing popularity of policies and standards of China's building energy efficiency , combining the economic and climate characters in the hot summer and cold winter zone and advantages of cavity wall used for building thermal insulation & energy saving, this paper researches on thermal resistance of cavity wall relative deeply, main contents as follows:1. This paper researches on the influence of temperature-humidity to material thermal conductivity. Thermal conductivity coefficient and impact factors of 4 components materials of cavity wall are researched deeply, while the impact factors including temperature and humidity .The result shows that, humidity has a great influence on thermal conductivity coefficient of the component materials, in addition, comparing with the influence on conductivity coefficient of all component material from moisture content, the one of temperature can be not considered. At the same time, according to distribution character and tendency of experimental data point, experimental data of all materials are fitted under common temperature and humidity condition, and regression equation with high degree of fit is given, which provides the basis for research of wall conductivity coefficient.2. This paper has a deep research on thermal resistance of cavity wall. According to research on tests of cavity wall thermal resistance with different thickness, cavity wall with polystyrene insulation boards-40mm, 20mm thick(air layers are set) can satisfy building energy saving standard and requirement in hot summer and cold winter zone. The result shows that, under the climate condition in hot summer and cold winter zone, the influence on conductivity coefficient from cavity wall inner moisture content, while the one of temperature (difference in temperature) can be not considered. What's more, thermal resistance can be improved if air layers are set and promoting and using cavity wall will contribute to implementation and popularization of China's building energy saving policy.3. According to theories and experiments, this paper test condensation phenomenon of cavity wall. The text shows that, cavity wall with polystyrene insulation boards will not appear condensation generally. In hot summer and cold winter zone, inside this cavity wall, condensation phenomenon will not appear which affects building function and working life.Research results and relative conclusions in this paper show that, implementing and popularizing cavity wall in hot summer and cold winter zone is feasible and effective.