How to Control DOAS Set point

asked 2018-03-28 12:13:45 -0500

Siva

295 ●1 ●5

updated 2018-03-28 15:37:22 -0500

__AmirRoth__

4436 ●5 ●17 http://bleedinggreenna...

Want to model Both Radiant cooling and DOAS system. But the purpose of DOAS system would be just to cater Latent Load. i want only minimal amount of sensible load to be met by DOAS system. I want Radiant Cooling system to take care of entire (major portion) of sensible load. When I tried to model DOAS and Radiant Cooling system together, I am ending up in getting temperature near to thermostat but it seems DOAS is the major contributor to that. How to control the cooling effect of DOAS system?

answered 2018-03-28 14:20:24 -0500

mdahlhausen

9314 ●17 ●11 http://openstudio.net/

Can you specify and tag which software you are using?

Assuming OpenStudio/EnergyPlus:

General steps for this are:

Use a setpoint manager scheduled to set a target supply air temperature on your DOAS air loop, e.g. 70F.
Use a setpoint manager scheduled to set a maximum humidity ratio after your cooling coil, e.g. the humidity ratio corresponding to a dewpoint of 55F.
Set air loop Sizing:System object "Type of Load to Size On" to VentilationRequirement.
If you have a zonal radiant system (e.g. radiant slab) that is not integrated with the air distribution as a zone air terminals, you'll also need to set your Sizing:Zone objects for each thermal zone to account for the dedicated outdoor air system and set the design supply air temperatures. Keep in mind that zonal radiant slab object control is tricky in OpenStudio/EnergyPlus; see other posts on the forum for help. You may just want to model slabs as fan coils if it's early stage design.