Analysis Of Elastic Mechanical Properties And Thermal Conductivity Of Heterogeneous Porous Foam

Porous foams are a new functional materials which composed with pore edges or walls. Compared with traditional materials, porous foams have lower apparent density, larger surface area, endurance of high temperatures and corrosions. With the rapid development of aerospace, automotive, electronic technology and other industries, materials with better qualities including excellent thermal performance, good mechanical properties, shock absorption, energy absorption and so on are required. Compared with the conventional materials, porous foams can better meet these requirements and adapt to development. So it is very important to study the performances of porous foams.Compared with continuous media, porous foam contains a large bunch of pores. The presence of pores causes many difficulties when predicting the properties of porous foams. Currently, prior researches on the properties of the foams only consider the effects of porosity. But the actual porous foams are non-homogeneous. Apparently, the randomness of pore size and distributions influences the properties of porous foams also. The affection of heterogeneity structure to the elastic mechanical properties and thermal conductivity has been studied through numerical simulation in this paper. The main research content includes:Two kinds of three-dimensional models of a porous foam were established: D-R heterogeneous models and D-C-R heterogeneous models Then, different uniformity of two kinds of models were defined and use them to descript the randomness of heterogeneous foams.The elastic mechanical properties of D-R heterogeneous models were studied. D-R heterogeneous models were set up in Auto CAD and all of them were imported ANSYS for numerical simulations of.linear elastic compression process. The relatively elastic modulus of the porous foams were calculated. The results show that the relatively elastic modulus was effected by porosity and pore uniformity. With the decrease of the pore uniformity, material randomness increases and the relatively elastic modulus decreases. The prediction equation of relatively elastic modulus was proposed basing data.The thermal conductivity of D-C-R heterogeneous models were studied. D-C-R heterogeneous models were set up in Auto CAD and all of them were imported ANSYS for finite element analysis of heat conduction. The relatively thermal conductivity of porous foams were calculated. Based on the results, the relatively thermal conductivity was effected by porosity and pore uniformity. With the decrease of the pore uniformity, material randomness increases and the relatively thermal conductivity decreases. The prediction equation of relatively thermal conductivity was proposed basing data.