Introduction of air infiltration and ventilation in a simple modelling for energy consumption estimation in air conditioned buildings.

This study reports on the introduction of air infiltration and mechanical ventilationin a model for energy consumption estimation. The model applies to air conditionned nonresidential building and is developped to need few inputs. Existing air infiltration models arecompared and three equivalent leakage area (ELA) databases are tested on the same casestudy. Calculations of air input throught opened-doors are made to compare flows due to airinfiltration and due to natural ventilation. Simulations are made considering mean airinfiltration value and hourly values. It appears that impact of air infiltration variation is nonegligible in winter (+11 % compared with mean air infiltration value).Then concerning mechanical ventilation, this study reports on taking intoconsideration in the model. The first solution is to introduce mechanicaloutdoor air flow rate in building loads. The second solution is to calculate building loadswithout outdoor air flow rate and to introduce it in mixing box calculation. Both solutions arenot equivalent concerning energy consumption (difference +16% for particular system used).