[TRNSYS-users] Possible data error in TM2 Weather File and circumventing solar radiation error messages

[Matt Duffy]

Ciarán, 

I was not able to recreate horizontal extraterrestrial
warning in version 16.1 or the current 17.1. If you could please send me
your *.tpf and listing (*.lst) file, I will try to provide some insight.


Thank you, 

Matt Duffy 

On 2013-02-07 11:42, Flynn Ciaran wrote: 

>
Hello everyone, 
> 
> I have a question concerning the validity of the
solar data in the FI-Helsinki-Airport-29740.tm2 weather file. 
> 
>
After running my simulation with a typical year of Helsinki weather, I
got the following errors concerning solar data: 
> 
> _"The calculated
total horizontal radiation exceeded the horizontal extraterrestrial
radiation and was set to the extraterrestrial for 1212 timesteps during
the simulation"_ 
> 
> _"The calculated horizontal beam radiation
exceeded the provided total horizontal radiation and was set to the
total horizontal radiation for 4 timesteps during the simulation"_ 
> 
>
To get the typical solar data for Helsinki, I modified the global
horizontal, direct normal and diffuse horizontal solar data in the tm2
file (according to: _Development of weighting factors for climate
variables for selecting the energy reference year according to the EN
ISO 15927-4 standard. _Kalamees, T., Jylhä, K., Tietäväinen, H.,
Jokisalo, J., Ilomets, S., Hyvönen, R. and Saku, S. Vols. Energy and
Buildings 47 (2012) 53-60.), leaving the extraterrestrial data
untouched. 
> 
> I found out that one reason behind the errors was that
the extraterrestrial solar data do not seem to be valid. For example, in
the tm2 file, there are only 5 hours of extraterrestrial solar data for
the shortest days of the year. In reality however, the minimum daylight
hours is just under 6 hours… 
> 
> So my question is, does anyone know
of a valid method to circumvent this inconsistent extraterrestrial data
problem? Can I simply set all of the extraterrestrial radiation values
to a high number throughout the year (and how useful are these if
non-extraterrestrial radiation data are already provided)? 
> 
> Thank
you for your help, 
> 
> Ciarán 
> 
>
_----------------------------------------_ 
> 
> _Ciarán Flynn_ 
> 
>
_Project Researcher_ 
> 
> _Aalto University - Department of Energy
Technology_ 
> 
> _P.O.Box 14100, 00076 Aalto_ 
> 
> _Otakaari 4, 02150
ESPOO_
 
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