Identification, generation of autoclaved aerated concrete pore structure and simulation of its influence on thermal conductivity

•The pore diameter and pore number of AAC were obtained through the image.•The air pores of AAC were generated, and the AAC model was built by software.•The relationship between thermal conductivity/porosity and pore size was obtained. The pore structure has great influence on the mechanical properties and thermal conductivity of autoclaved aerated concrete(AAC). In this study, through the binary processing of the surface image of AAC, the pore diameter and number of AAC were obtained. Based on Monte Carlo method, the spherical coordinates of the air pores of AAC were generated by MATLAB software, and then they were imported into ANSYS software for modeling and grid generation. By comparing the pore size distribution and thermal conductivity between the finite element model and AAC product, to some extent, the finite element model in this paper is feasible. By the finite element analysis, the thermal conductivity is inversely proportional to the porosity and directly proportional to the pore diameter. Based on the thermal conductivity prediction model of porous materials, the mathematical models of porosity and thermal conductivity, pore diameter and thermal conductivity of AAC were established.