Experimental Device Research On The Heat And Moisture Transfer In Wall Composed With External Thermal And Wet Insulation In Severe Cold Area

At present,our country construction energy consumption accounts for about 30% of the GDP energy consumption in the whole society.Energy conservation and emission reduction is focused on building energy conservation,and the key to building energy conservation is the enclosure structure energy saving.Based on this,efficient thermal insulation material has been developed rapidly.The exterior wall insulation technology can avoid moisture condensation of the inner surface of the containment structure,but sometimes the internal space of the composite wall will still produce condensation.Therefore,the problem analysis of exterior wall's heat-moisture transfer is gradually becoming the subject direction,to which industry researchers pay special attention.It includes the research on the moisture transfer in porous building materials,the research on heat-moisture transfer properties of thermal and moisture-insulating wall,and the research on coefficient of thermal conduction's changes with moisture content.This paper briefly describes several common hot and humid-box methods,which are used to measure the thermal parameters of building composite walls.Besides,the protective heat-box method and the calibrated heat-box method are mainly introduced,related to the topic.Combining the advantages of both,the hot and humid-box laboratory is designed and constructed,considering the conditions of indoor and outdoor meteorological parameters in our country and the level of existing experimental equipment and methods at the same time.Firstly,based on the analysis,the principle,composition and raw materials of the experimental platform are determined,and the design calculation of the main components is completed.The experimental platform can determine the internal temperature-humidity field,the heat transfer coefficient and steam permeability coefficient of the composite wall under different working conditions.It can also be used to verify the heat transfer theory of porous medium.The thermal parameters of the experimental platform are automatically measured in the field,and the output of the meters is recorded to avoid the effect of artificial reading.The experiment platform has designed the complementary self-regulating system and improved the stability of the system.Secondly,after the setup was completed,the test piece of the STP external-insulation composite wall is made,and the size is 2.1m by 1.8m by the thickness of 0.24 m.Finally,the relevant errors of this experimental platform are analyzed,including heat transfer coefficient and steam permeability coefficient.