Re: [TRNSYS-users] Question of active layer

[David BRADLEY <d.bradley@tess-inc.com>]

Wang,

> 1. The floor heating area is 27.2 m^2 in our test room, but the floor 
> area is 40 m^2. Like this situation, Can I set two floors in TRNBuild? 
> One is the floor  with 40 m^2, another is floor with 27.2 m^2 active 
> layer? Or others?
 yes, you can define two floors in your TRNBuild zone. If the total 
floor area is 40m2 and the active heating area is 27.2m2 you would 
define one floor with an active layer having an area of 27.2 m2 and 
another floor (without an active layer) with an area of 12.8m2. It is 
worth noting that the two floors in the model will be completely 
thermally isolated from each other while in your test room, there is 
probably some energy exchange between the actively heated area and the 
non heated area. Still, I think you will get a good representation of 
what is happening in the zone.
> 2. I only know the power of this floor heating 1400 W. How can I 
> define it? Or by what method to stand for this power?
is this an electrically heated radiant floor? If so then you can define 
a wall gain (some energy gain that occurs inside the wall) in TRNBuild 
where you declare the wall within your zone. The active layer model is 
intended for radiant floor systems that employ a liquid piping network. 
If you do have a liquid piping network in the floor then when you 
specify the active layer in your modeled zone, you have the ability to 
not only define the inlet temperature and mass flow rate but also the 
energy gain. See page 5-58 of the 05-Multizone Building volume of the 
TRNSYS 17 documentation set.

Regards,
 David


--
***************************
David BRADLEY
Principal
Thermal Energy Systems Specialists, LLC
22 North Carroll Street - suite 370
Madison, WI  53703 USA

P:+1.608.274.2577
F:+1.608.278.1475
d.bradley@tess-inc.com

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