The present study results from a research collaboration between Laboratory ERMeP (GIP-InSIC) and the company Nordon-Cryogenie (Vosges, France), one of the major world manufacturers of heat exchangers for cryogenic processes. A general description of a multi-stream brazed aluminium plate-fin heat exchanger is presented in Fig 1. The problem for Nordon Cryogénie is to guarantee a thermal performance as well as the safety of the heat exchanger by ensuring the structural integrity of each stream subjected to pressure and temperature gradients.
The current research program consists in the development of a dedicated FEM solver for the global thermo-elastic analysis of an exchanger. Since a complete FEM model would lead to several millions of structural elements (solid, shell) we propose a simplified 3D FEM model based on homogeneization techniques to obtain the equivalent (effective) stress-strain relations and equivalent thermal load vectors of the corrugated fins brazed with the plate layers (Fig. 1). Two approaches are considered (kinematical and mechanical models) while considering periodicity. The implementation of these two methods is performed using the free finite element software Code_Aster.
Dib J., Bilteryst F., Batoz J.-L., Lewon I. : Application des techniques d’homogénéisation pour l’analyse tridimensionelle d’échangeurs de chaleur à plaques et ondes. Actes du 7ème Colloque National en Calcul des Structures, Giens 2005, Vol.I, 417-422, Lavoisier, France, 2005.