Substitute thermal conductivity coefficient for multi-component ceramic materials

On the example of granular material (as quartz sand bonded by resin, used for mould production in metallic alloy casting—in foundry industry), the phenomenon complexity level in a such porous material during heat transfer, is presented. Accurate modelling of these phenomena (superposition) is of limited meaning, because of incomplete material data bases, that are needed in this case. Practical solution is based on the application of simplified models as for non-porous, homogenous, solid materials. This fact requires the knowledge of the substitute thermal conductivity coefficient (λsubstit). In the paper, the second practical proposal is justified. The methodology of λsubstit determination, by inverse solution related to experiment, is described. The coefficient λsubstit depends on the local temperature and on the time of various temperature influences in the same place of material. The effectiveness of λsubstit using the computer simulation of heat chock, in described mould material, e.g. during metallic alloy casting, is also proved.