Dear Ayman,
do you mean the 4th input
of Type 56 TSGRD?
This temperature input is
used for longwave radiation exchange of an external surfaces with the environment.
The environment is
divided into 2 parts
- the sky presented by a sky
temperature TSKY and the view factor to the sky FSKY and
- the “non-sky”
part called ground presented by a ground temperature TSGRD and the view factor
1-FSKY.
If the building is
surrounded by other buildings the walls doesn’t “see” the
ground that much but the other buildings.
In this case TSGRD should
represent the surface temperature of the other buildings.
Best,
Marion
Dipl.-Ing.
Marion Hiller
TRANSSOLAR:
KlimaEngineering - Technologien für energieeffizientes Bauen und Nutzerkomfort
in Gebäude
Munich - New York - Stuttgart + 49.711.67976.0
Transsolar
Energietechnik GmbH, Curiestrasse 2, 70563 Stuttgart
Amtsgericht Stuttgart - HRB 23347, Steuernummer 99073/00911, USt-IdNr.:
DE152272639
Geschäftsführer:
Dipl.Ing. Matthias Schuler, Dipl.Ing. Thomas Auer, Dipl.Phys. Stefan Holst, Prof. Dipl.-Ing. Bleicher
Von: Ayman Sarwa
[mailto:aymaneldakhl@yahoo.com]
Gesendet: Samstag, 6. August 2011
12:20
An: David BRADLEY; trnsys-users@cae.wisc.edu
Betreff: Re: [TRNSYS-users]
Boundary wall
But ,
what is the importance or function of Tground as an Input in Type 56 ?
From: David
BRADLEY <d.bradley@tess-inc.com>
To: Ayman Sarwa
<aymaneldakhl@yahoo.com>
Cc: "trnsys-users@cae.wisc.edu"
<trnsys-users@cae.wisc.edu>
Sent: Friday, August 5, 2011 10:44
PM
Subject: Re: [TRNSYS-users]
Boundary wall
Ayman,
I am not sure that I follow quite what you are doing. If your floor is
defined as a BOUNDARY and the back side temperature is set to identical then
that defines an air temperature on the other side of the floor as being
identical to the air temperature of your zone. You can't then define the back
side temperature as a ground temperature; that would doubly define the
temperature on the other side of the floor.
Best,
David
On 8/5/2011 09:50, Ayman Sarwa wrote:
I am
simulating single zone by Trnbuild and Trnsys 17, I define the floor as boundary and select boundary as identical when I read the energy
from inside surf. of floor conv. to air and
longwave radiation to other surfaces = NTYPE19 the QCOMI of
floor, and Temp. of inside floor, I note that,
for all
cases when I define the ground Temp i.e Input of type 56 by type 77 (ground
temp ) or by const value , the QCOMI always keeps +ve while T sur_in < T
zone, i.e the energy transfer from air zone to floor , but QCOMI must be -ve, Why ?
Any one can help me to
Know what is happen ?
_______________________________________________
TRNSYS-users mailing list
TRNSYS-users@cae.wisc.edu
https://mailman.cae.wisc.edu/listinfo/trnsys-users
--
***************************
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
http://www.tess-inc.com
http://www.trnsys.com