How can we measure the airflow rate from one zone to another zone in EnergyPlus in air changes per hour?

edit

I don´t know if there is a output that gives the ACH, but you can use the output variable Zone Mixing Current Density Volume Flow Rate [m3/s]The air volumetric flow rate in m3/s entering the zone due to the sum of mixing, cross-mixing, andrefrigeration-door mixing during the hour or timestep using the density of air evaluated at current zoneair conditions.

Then you can convert the m3/s to ACH.