NATURAL VENTILATION OF RESIDENTIALBUILDINGS IN PORTUGUESE WINTER CLIMATICCONDITIONS

摘要

In this paper, the current situation of Portuguese residential buildings in terms of ventilation systems ispresented. The indoor air renewal is, normally, obtained by providing fresh air exclusively by air leakage ofdoors and windows and their occasional opening and exhausting the air through ducts placed in kitchens andbathrooms. A recent revision of the Portuguese standard NP 1037-1, concerning natural ventilation of dwellings,is studied and its influence upon heating energy consumption and indoor temperatures is reported. In order toevaluate both thermal and ventilation impact of the adoption of NP 1037-1, a dynamic simulation wasundertaken, using Trynsis 15 and Comis 3.1 software. Some results of this study concerning a residentialbuilding, located in different Portuguese winter climatic regions, are presented. The relative influence of bothwind and thermal stack effect has been evaluated, the cooling effect of ventilation for unheated indoorenvironments has been quantified and the importance of parameters like the location of the dwelling in thebuilding, its orientation and the opening height have been analysed. Some ventilation devices were simulated,like self-regulated inlet grilles (trickle ventilators). Finally, other strategies of improving ventilation, keeping lowheating energy consumption, have been considered, namely demand controlled ventilation.