[TRNSYS-users] thermal bridge

[Diego A. Arias]

Hi Nicola,

nicola wrote:
> Dear all,
> I'm modelling a wall wit a thermal bridge effect.
> I found a bug in TRNBuilt :
> 1. If I put the value of resistence equal to xxx (hmK/kJ) in the layer 
> manager, the program create a wall with a U-value expressed in kJ/h 
> m^2K and a resistence equal to xxx in hm^2k/kJ!!!
Thanks for finding this bug. I think it is only a problem of displaying 
the units.  The resistance should be entered in h m^2K /kJ, and not h m 
K /kJ.  When you check on the 'Layer type manager', the resistance is 
shown in h m^2K /kJ.
> 2. the u-value of a wall with thermal bridge effect is lower than the 
> same wall without thermal bridge effect.
The u-value displayed in the 'Wall type manager' is calculated by adding 
two reference heat transfer coefficients to the wall (7.7 and 25 W/m^2 K).

Best regards,

Diego

-- 
Diego A. Arias
TRNSYS Coordinator
Solar Energy Laboratory
University of Wisconsin - Madison
1500 Engineering Drive
Madison, WI 53706