[TRNSYS-users] U value problem

[Yoshihiro Yamaguchi]

Dear Yuki,

U-value of window cannot be changed by only editing U-value in BUI file.
Type56 Window model is similar to Wall model, which several layers make
one window in Type56. Layer has its own angular dependent optical 
and thermal characteristics.

You can make a new window by using Window 5.x available on LBNL web site.
Fortunately, now you can find a good tutorial on SEL web site.
http://sel.me.wisc.edu/trnsys/downloads/tutorials_and_examples/tutex.htm

You may get a new window having desired U-value.

Good luck!

Yoshihiro

> Dear all,
> 
> I try to change only the U value of the window by editing the BUI file, but
> it is not possible to correct it.
> I have changed U value without changing an optical characteristic of the
> window.
> When U value was output via SimulationStudio, it has no change, while the
> output of TRNBuild gave the changed U value.
> 
> The corrected part is shown as follows.
> 
> Window U value of BUI file
> ****************Value Before**************************************
> Overall and Center of Glass Ig U-values (W/m2-C)
> Outdoor Temperature                 -17.8 C      15.6 C      26.7 C
> 37.8 C
> Solar      WdSpd  hcout hrout  hin
> (W/m2)     (m/s)     (W/m2-C)
> 0        0.00  12.25  3.43  8.23  5.30 5.30  4.98 4.98  4.97 4.97  5.57 5.57
> 0        6.71  25.47  3.34  8.30  6.31 6.31  5.77 5.77  5.72 5.72  6.51 6.51
> 783        0.00  12.25  3.47  8.19  5.29 5.29  4.80 4.80  5.19 5.19  5.66
> 5.66
> 783        6.71  25.47  3.36  8.28  6.30 6.30  5.64 5.64  5.91 5.91  6.59
> 6.59
> 
> ****************Changing Value*************************************
> Overall and Center of Glass Ig U-values (W/m2-C)
> Outdoor Temperature                 -17.8 C      15.6 C      26.7 C
> 37.8 C
> Solar      WdSpd  hcout hrout  hin
> (W/m2)     (m/s)     (W/m2-C)
> 0        0.00  12.25  3.43  8.23  6.03 6.03  5.67 5.67  5.66 5.66  6.34 6.34
> 0        6.71  25.47  3.34  8.30  7.18 7.18  6.57 6.57  6.51 6.51  7.41 7.41
> 783        0.00  12.25  3.47  8.19  6.02 6.02  5.46 5.46  5.91 5.91  6.44
> 6.44
> 783        6.71  25.47  3.36  8.28  7.17 7.17  6.42 6.42  6.73 6.73  7.50
> 7.50
> 
> 
> And, I have two question.
> 1. Is the method of changing U value suitable?
> 2. How should I do so that only U value may change without changing 
> an optical characteristic in the window?
> 
> Thanks in advance
> 
> Yuki SASAKI
> 
> 

=====================================
  Yoshihiro Yamaguchi    山口　芳弘  
  yamaguti at alpha-net.ne.jp
=====================================