[TRNSYS-users] Floor Heating - Trnsys3D

[David BRADLEY]

Hoofar,

   If you click on the "Geometry Modes" button in a given zone you can 
switch one or more zones to "manual mode." This allows you to create the 
geometry in Trnsys3d but then autosegment the floors of a particular 
zone afterwards. The disadvantage, of course, is that once you switch a 
zone to manual mode you cannot then go back and edit the building 
geometry in Trnsys3D.


   If you do not want to switch to manual mode then here are some 
responses to your questions:


1) How should be the surfaces split in Trnsys3D? Have I used the right 
approach?

I believe that what you've done is reasonable. The autosegment feature 
puts a number of smaller floor areas in series.

2) How can they be manually connected?  (when the Autosegmentation is 
done, surfaces are automatically connected in series with automatic 
inlet temperature and the same inlet flow rate)

I think you will need to do this by adding outputs and inputs to your 
Type56 model. The connections will need to be done outside of Type56 in 
the Simulation Studio.

3) After splitting the floors, which output shows the overall heat 
transfer to the zone and which one shows the final outlet fluid temperature?

I think that for the overall heat transfer to the zone you'll need to 
sum up a number of Type556 outputs. The overall heat transfer to the 
zone will be the sum of the heat transfer to the zone from each 
individual floor piece. The final outlet temperature will depend upon 
the order in which you connect the floors to one another in the 
Simulation Studio. I'd suggest using the surface IDs that TRNBuild 
assigns and drawing a picture so that you can keep all the connections 
straight.

4) What should be the standard number of fluid loops per square meter?

There is an equation in the TRNBuild/Type56 manual that suggests a way 
of computing the number of loops based on how long you want each 
individual pipe to be.

kind regards,
  David



On 03/21/2020 11:38, Hemmatabady, Hoofar via TRNSYS-users wrote:
> Hello,
>
> I am working on a project on heating a house with a heat pump. I 
> designed a Trnsys3D model of the house, which I need to implement a 
> floor heating system on it. After adding an active layer in TRNbuild, 
> got the error "Specific fluid mass flow of active layer in surface  16 
> below minimum value of 2.96 kg/m2h Please, increase the minimum mass 
> flow rate or use the autosegmentation feature of TRNBuild for 
> subdividing the surface.".
>
> As I have a 3d model, the Autosegmentation is not possible. Therefore, 
> following TRNbuild documentation "For airnodes with 3D geometric 
> information the splitting of surfaces have to be done in Trnsys3D and 
> then manually connected",  I split my floors (in Sketchup) into 20 
> equal surfaces using parallel lines and imported my 3d model back to 
> TRNbuild.
>
> Here are my questions:
>
> 1) How should be the surfaces split in Trnsys3D? Have I used the right 
> approach?
> 2) How can they be manually connected?  (when the Autosegmentation is 
> done, surfaces are automatically connected in series with automatic 
> inlet temperature and the same inlet flow rate)
> 3) After splitting the floors, which output shows the overall heat 
> transfer to the zone and which one shows the final outlet fluid 
> temperature?
> 4) What should be the standard number of fluid loops per square meter?
>
>
> Best regards
> Hoofar Hemmatabady
>
>
>
>
> _______________________________________________
> 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
F:+1.608.278.1475
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/20200323/d3597864/attachment.html>