I am modelling a building with an air handling unit supplying air to zones at a given temperature and flow rate. The air is conditioned at zone level by terminal units. The building is mechanically ventilated i.e. no fresh air introduced at zone level, only at the AHU. I have very little information on the actual terminal units and AHU themselves in terms of system specs.
The metering strategy for the building covers the AHU on one meter and the zones' terminal units on another meter. I'd like to match the output from the EnergyPlus model to the metered energy. However, I have very little information on the system components. Fully defining HVAC adds a lot of uncertainty (dozens of variables for chiller loops, boiler parameters, airflow branches etc.).
I have been modelling the HVAC at zone level using ZoneHVAC:IdealLoadsAirSystem objects. From my understanding of the IdealLoads object it models an idealised VAV but the building in question has a fixed flow going to the zones. Also, I'd like to explicitly define ventilation from the AHU (flow rate from the AHU is one piece of information I do have).
Is there a way to model the system that gives more insight than the IdealLoads but without the full complexity of a fully defined HVAC system? For example, using a dummy zone to represent an AHU and linking it to the zones through an AirFlow Network?
