Coupled heat transfer and thermal stress analysis of composite lattice core sandwich structure

A simulation was carried out for the coupled conduction and radiation heat transfer in the all-composite lattice core sandwich structure. The cavity radiation method was used firstly to detect the radiation contribution to the heat transfer, and then a discussion for the effect factors of this contribution was followed, such as the participation of the lattice truss core and the surface emissivity of the composite materials. Finally, the thermal deformation and thermal stress was calculated on the basis of the known temperature field by coupled simulation. It was shown that the radiation effect was obvious when the structural temperature was around 350°C, and this effect was enhanced as the emissivity increased; the contribution of lattice truss core to the heat radiation was small. As the upper and under sheets fixed, thermal stress happened mainly in the upper facesheet and at the endwalls where the cylinders contacted with the upper facesheet. The distribution of thermal stress field depends on the restriction forms, and the max thermal stress is smallest only as the upper sheet is fixed.