# DOAS modeling with varying/scheduled OA cfm

Currently I am modeling a high-rise residential building and specifically have issues on modeling DOAS.

- MAU supplying OA at 72F to residential units: Design supply air flow rate (Max) and hourly actual cfm needed are known (smaller than max).

Firstly, I've tried to mimic the DOAS system using AHU (vav) with min/max fraction of OA schedules.

- OA flow rate is working as intended (checked system OA flow rates), but realized this is not anymore 100% OA, but a fraction of it.

So here I am wondering if there is any way to model this AHU (actually DOAS) with varying OA (=SA) CFM following the schedule value I made based on a real-life OA flow rate calculated each hour.

In summary, wondering the way to model DOAS system in EnergyPlus,

1) 100% Outdoor Air

2) conditioned to 72F using H/C coils

3) Max OA (=SA) design air flow rate known

4) different/varying hourly CFM during the day known

5) so hourly OA (=SA) flow rates following the schedule, not the count of people or CO2 or else.

Thank you so much for any kind of helps/insights/comments in advance!