Theoretical and experimental study of heat transfer through a vertical partitioned enclosure: Application to the optimization of the thermal resistance

Enclosures divided by multiple vertical diffusive partitions have high insulating qualities and may provide tangible benefits as a construction material. In this study, we have developed one-dimensional analytical model of coupled heat transfer (conduction, convection, radiation) in such enclosures. This model is numerically and experimentally validated for an important number of configurations and size of alveolus. The variation of the thermal resistance versus the number of partitions has been experimentally validated. The model is then used to find the partitions number that maximizes the thermal resistance of a partitioned enclosure. Effects of thermal and geometrical parameters on the maximal thermal resistance of the partitioned enclosure have been also investigated. We have shown that the thermal resistance could be improved by decreasing the thermal conductivity of walls; decreasing the emissivity of the partitions faces; or using very thin partitions. The use of relatively thick exterior vertical walls marginally degrades the optimal thermal resistance while at the same time increases the thermal inertia. The combination of the different parameters gives a set of solutions when one desires to obtain precise characteristics for an insulating envelope. The presented model can help to determine the most suitable combination of parameters allowing to get the desired maximal thermal resistance.