Archsim can simulate natural ventilation in 3 different modes.
- Simple wind and stack equations
- Airflow network
The first option is great for coupling Archsim with other tools that return a schedule of air-changes in hourly format. Just link this schedule in the zone settings under the ventilation tab or specify a fixed air change rate.This model does not model airflow from zone to zone.
The second option uses simple formulas explained on the slides below. This model is extremely robust – especially for buoyancy driven flow. Wind driven flow always assumes an ideal exhaust and basically simulates cross-ventilation – even if you only model one window – this can easily lead to overestimation of the wind driven ventilation potential. This model does not model airflow from zone to zone.
The third option is the airflow network. It provides the possibility to model natural ventilation and more complicated airflow paths through the building. Thus, this is the preferred option – however – it might slow down your simulations.