A substructuring approach to 3D conduction probelms: aplications to buildings' components

The present  paper  describes  how  the  use of a modal synthesis method in the study of the thermal behaviour of buildings both facilitates and hastes the modelling step concerning the problem of linear conduction in multidimensional components. This work is divided into three sections: we first intro­ duce the substructuring approach applied to modal formulation; we then formally describe, through a simplified bidimensional example, the synthesis step leading to a global evolution model computed by substructuration. Supported by tools developped at GISE and illustrating our results with thermograms, we then compare the results obtained by this method (based on a finite element discretization) with those of a reference computed directly (temperature field and heat flows). Finally, a larger problem of a 3D thermal bridge is treated to emphasize the relevance of the method in terms of computational resources when dealing with average-model computer: CPU time but also memory limitation.