How to model natural cross ventilation with airflow network?

edit

a simple recipe is as follows: specify

• the zones for natural ventilation via AirflowNetwork:MultiZone:Zone
• the Surfaces with leakage components (AirflowNetwork:MultiZone:Surface)
• leakage components [horizontal and vertical openings and cracks] are defined via (AirFlowNetwork:Multizone:Component:* or ...:MultiZone:Surface:Crack) you will need some assumptions or data on air mass flow when opening is closed, discharge coefficients etc.
• external nodes (AirflowNetwork:MultiZone:ExternalNode) for affected facades, roof surfaces, with associated wind pressure coefficient specs
• AirflowNetwork:SimulationControl details

With pure natural ventilation, you will not have control over the direction of airflows, in fact there will usually occur flows in both opposite directions. This can be monitored via appropriate output variables.

However, there is the option of using venting controls for zones and openings. As an example, you may find more details here.