Abstract(s) :
(Anglais) The earth-air heat exchanger (EAHE) or “Puits canadien” in French consists of buried pipes for the hygienic ventilation of a building. This allows a preheating of the ventilation air in winter and a passive cooling in summer. This technique uses the thermal capacity of the earth to buffer and phase out the periodic variation of the outside temperature. Various numerical models, validated by experimental measurements, have been made to simulate heat transfer and condensation over a period of one year. To resolve the unsteady 3D configuration of the problem, a pseudo 3D model was used to determine the temperature field. As the circulating air also carries moisture, a phenomenon of condensation will take place, creating a particular biotope that can contaminate the hygienic air by the biocenosis. The first part of the study is the condensate evaluation. It will be supplemented in a second step by a metagenomic study of biocenosis.