Study On Thermal Performance Of Aerogel Foamed Concrete And Its Influencing Factors

The huge scale of buildings in China needs to consume a lot of energy.Using building thermal insulation materials to improve the thermal performance of building envelope can effectively reduce the heating and cooling load of the building.Foamed concrete has high porosity and low thermal conductivity,and can play a role of heat preservation and insulation for building envelope structure.The super thermal gel material with ultra-low thermal conductivity and ultra-low density was added into the foam concrete to further improve the thermal insulation performance of the foam concrete.In this paper,super adiabatic(<0.026W/(m·K),less than static air)and ultra-light aerogel(<100 kg/m~3)powders were filled into the foamed concrete to produce aerogel foamed concrete.The thermal conductivity of aerogel foamed concrete was obtained by experimental test and model simulation.The influences of aerogel density,particle size and content on thermal conductivity of aerogel foamed concrete were studied.Firstly,aerogel foamed concrete was prepared by super adiabatic and super light aerogel filling experiment.The effects of porosity,particle size and content of aerogel on the density,thermal conductivity and compressive strength of foamed concrete were studied.Secondly,the aerogel content and other parameters were optimized.It was found that when the aerogel and foam content(volume ratio)were 13%and 70%,respectively,the strength of aerogel foamed concrete met the standard requirements,and the density and thermal conductivity of foamed concrete were 185.9kg/m~3and 0.058W/(m·K),respectively.The density and thermal conductivity of the foamed concrete decreased by about 10%and the aerogel mass dosage decreased by 54%when compared with the higher density aerogel filling(208.5kg/m~3,thermal conductivity 0.067W/(m·K))with the same addition amount(volume ratio).Finally,a simplified calculation model for the composite thermal conductivity of three components in aerogel foamed concrete was established,and the accuracy of the simplified calculation model was verified by comparing the calculated values with the measured values.The research results of this paper can provide experimental data and model calculation reference for the development and application of high-performance foamed concrete,improve the thermal insulation performance of buildings,and promote the development of building energy saving and carbon reduction technology.