[TRNSYS-users] Type 508 (Cooling Coil): Outlet air temperature higher than setpoint

David BRADLEY d.bradley at tess-inc.com
Tue Jun 15 09:31:10 PDT 2021


José Javier,

  I would put a Type65 on the cooling coil to see the inlet and outlet 
temperatures and flowrates on both the air and water sides as the 
simulation progresses. I think you may find that the inlet liquid 
temperature may not always be coming in as cold as you need it to in 
order to bring the air temperature down as far as 2.8C.

  Also make sure that there is some thermal capacitance in the liquid 
loop. If you have just the cooling coil, a pump, and a chiller (or 
whatever device is providing the cold liquid) then you'll want to add 
pipes and/or a tank so that the loop is numerically stable as so as to 
more accurately model the transient impact of the loop heating up and 
cooling down as a function of time (rather than instantaneously because 
you are only using quasi steady state models)

kind regards,

  David


On 06/15/2021 09:28, RUBIO RUBIO, JOSÉ JAVIER via TRNSYS-users wrote:
>
> Dear all,
>
> I am using the Type 508 to model a cooling coil with the outlet air 
> temperature set to a constant value. As far as I am concerned, there 
> is enough air flowrate as well as fluid flowrate during the simulation 
> but the outlet air temperature is much higher than the setpoint (for 
> example, the setpoint is 2.8 ºC and the outlet air temperature is 12 
> ºC). Anyone can help me to understand why is that?
>
> Thanks in advance,
>
> Regards,
>
> José Javier Rubio Rubio.
>
>
> _______________________________________________
> TRNSYS-users mailing list
> TRNSYS-users at lists.onebuilding.org
> http://lists.onebuilding.org/listinfo.cgi/trnsys-users-onebuilding.org

-- 
***************************
David BRADLEY
Principal
Thermal Energy Systems Specialists, LLC
3 North Pinckney Street - suite 202
Madison, WI  53703 USA

P:+1.608.274.2577
d.bradley at tess-inc.com

http://www.tess-inc.com
http://www.trnsys.com

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/trnsys-users-onebuilding.org/attachments/20210615/d3285fc5/attachment.htm>


More information about the TRNSYS-users mailing list