Coupling TRNSYS 17 and CONTAM: simulation of a naturally ventilated double-skin façade

Aiming at developing a decision aid tool for double-skin façades (DSF) design in the Mediterranean climate, this study has coupled CONTAM with TRNSYS to evaluate the thermal/ventilation performance of the façade under dynamic climatic conditions. Similar coupling thermal building simulations to nodal airflow network simulations have been performed in DSF modelling; but in all cases, it was used to get an overall evaluation of the DSF behaviour, whereas, in this paper, temporal distribution of temperatures into the cavity is presented, relating more accurately the transient heat and mass transfer in the DSF. Reproducing a configuration of single storey naturally ventilated DSF reveals a good agreement between simulation results and measured data from full-scale experimentation in both winter and summer time. The 3D radiation model implemented in the last version of TRNSYS, provided with the detailed solar characteristics of glazing in the different layers of the DSF, well estimates the heat transfer into the cavity in interaction with the adjacent zones. Natural ventilation is obtained, using CONTAM, by means of internal airflow paths running through the DSF height.