[TRNSYS-users] Uvalue

hotline hotline at Transsolar.com
Wed Apr 20 07:22:38 PDT 2016


Dear Adnan,

please make sure that all other heat transfer effects (solar radiation, internal gains, convection, infiltration) besides heat flow through walls are switched off!
you can use NType 19…22 to determine the heat flows at the front and back side of the wall. And please keep in mind that TRNSYS will simulate capacitive effects, too.


        [cid:image002.png at 01D19B20.DACB9990]

Best
Jakob


_________________________________________________________________________________________________

Jakob Merk
TRNSYS Software Team

Transsolar Energietechnik GmbH
Curiestraße 2
70563 Stuttgart
Fax:        +49 711 67976-11
Email:    hotline at transsolar.com<mailto:hotline at transsolar.com>
Web:      www.trnsys.de<http://www.trnsys.de/>



Von: TRNSYS-users [mailto:trnsys-users-bounces at lists.onebuilding.org] Im Auftrag von Adnan Upm Spain
Gesendet: Mittwoch, 20. April 2016 16:07
An: TRNSYS users mailing list at OneBuilding.org
Betreff: Re: [TRNSYS-users] Uvalue


Thanks Merk for your reply...

I am using Ntype2 sensible heating demand and one out put Ntype 906 which give energy balance in it system also gives same value for heating.

Regards
Adnan

Sent from my Sony Xperia™ smartphone


---- hotline wrote ----
Dear Adnan,

your approach makes sense to me. TRNSYS does calculate heat transport for each time step and is not using a fixed U-Value.
Which TRNSYS outputs did use for q= convective and radiative heat loss ?
I guess that using a wrong output could have coused your problem…

Sincerely yours
Jakob Merk
_________________________________________________________________________________________________

Jakob Merk
TRNSYS Software Team

Transsolar Energietechnik GmbH
Curiestraße 2
70563 Stuttgart
Fax:        +49 711 67976-11
Email:    hotline at transsolar.com<mailto:hotline at transsolar.com>
Web:      www.trnsys.de<http://www.trnsys.de/>



Von: TRNSYS-users [mailto:trnsys-users-bounces at lists.onebuilding.org] Im Auftrag von adnan rasheed
Gesendet: Mittwoch, 20. April 2016 13:13
An: trnsys-users at lists.onebuilding.org<mailto:trnsys-users at lists.onebuilding.org>
Betreff: [TRNSYS-users] Uvalue

hi everyone,

i have one question i am stuck with this problem.

1- i want heating a room having one window, by using type 56

inside temp = 10, 20, 30,....

dry bulk temp= ambient  temp = outside = 0

sky temp = 0 and -20

i wanna see the change in overall heat transfer coefficient = u-value of glazing (window) by changing inside temperature using this equation

U = Q / A(T) where
U = U-value
q= convective and radiative heat loss
A = Area of window
T = ambient and inside temp difference.

i get results but TRNSYS giving me almost the same value of U for all temp difference. trend is not same as experimental U-value trend according to change in inside temp.

anyone please help me with this is it possible to calculate U-value of window like this. or trnsys use fix U-value for the calculation of heat load.

thanks in advance. for killing your time.

Regards
Adnan
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/trnsys-users-onebuilding.org/attachments/20160420/79edc66e/attachment-0001.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.emz
Type: application/octet-stream
Size: 265597 bytes
Desc: image001.emz
URL: <http://lists.onebuilding.org/pipermail/trnsys-users-onebuilding.org/attachments/20160420/79edc66e/attachment-0001.obj>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image002.png
Type: image/png
Size: 80392 bytes
Desc: image002.png
URL: <http://lists.onebuilding.org/pipermail/trnsys-users-onebuilding.org/attachments/20160420/79edc66e/attachment-0001.png>


More information about the TRNSYS-users mailing list