[TRNSYS-users] Problem Ventilation in TRNFLOW

[freppelw at noirot.fr]

Indeed, by reducing the timestep, it worked.

Than you

Wirich

Le 2017-12-01 00:00, Jean Marais via TRNSYS-users a écrit :
> reduce the time step?
> 
> Am 29.11.2017 3:50 nachm. schrieb "Wirich via TRNSYS-users"
> <trnsys-users at lists.onebuilding.org>:
> 
>> Dear Jakob,
>> 
>> Thank you for your reply. Indeed, I didn't realize that there was a
>> dead end in the CELLIER room. I added a duct to the ventilation
>> network and now it works.
>> 
>> However, this doesn't solve my heating problem. I realized that when
>> the heating power supply is not high enough to reach the target
>> temperature, the simulation stops, saying that the number of
>> iteration did not reach to a convergence.
>> Here is what I did exactly:
>> 1) I set up a heating power supply in the room SALON3, with 3600
>> kJ/h
>> The simulation stopped before the end
>> 2) I set up the heating demand to unlimited power
>> It worked
>> 3) I set up a heating power supply in all rooms, with 3600kJ/h each
>> It worked
>> 
>> Does someone know why? it seems that TRNFLOW is not steady when the
>> heating power supply is not high enough to reach the target
>> setpoint. I don't quite get why?
>> 
>> King regards
>> 
>> Wirich
>> 
>> Le 2017-11-28 09:29, hotline via TRNSYS-users a écrit :
>> 
>>> Dear Wirich,
>>> 
>>> " Flow matrix is singular" means, that the flow network cannot be
>>> solved. This can happen if nodes are not well connected. Two rules
>>> must be applied here:
>>> 
>>> * All nodes have to be connected in ONE network
>>> * Dead ends are not allowed.
>>> 
>>> In your model, rule1 is applied but rule2 not (see red circle in
>>> the
>>> ).
>>> 
>>> I connected them with three dummy cracks to make it work…
>>> 
>>> LINK CR_001       : ID= 29 : FRNODE= P4         : TONODE= CELLIER
>>> :
>>> FRHEIGHT=       0 : TOHEIGHT=        0 : WIOWNHF=       1 :
>>> FSCALE= 1
>>> 
>>> LINK CR_001       : ID= 32 : FRNODE= CELLIER    : TONODE= WC
>>> :
>>> FRHEIGHT=       0 : TOHEIGHT=        0 : WIOWNHF=       1 :
>>> FSCALE= 1
>>> 
>>> LINK CR_001       : ID= 33 : FRNODE= WC         : TONODE= SDB
>>> :
>>> FRHEIGHT=       0 : TOHEIGHT=        0 : WIOWNHF=       1 :
>>> FSCALE= 1
>>> 
>>> Best
>>> Jakob
>>> 
>>> 
>> 
> __________________________________________________________________________________________________
>>> 
>>> Jakob Merk M.Sc.
>>> 
>>> Transsolar Energietechnik GmbH
>>> 
>>> Curiestraße 2
>>> 
>>> 70563 Stuttgart
>>> 
>>> http://www.transsolar.com
>>> 
>>> Transsolar: KlimaEngineering- Technologien für energieeffizientes
>>> Bauen und Nutzerkomfort in Gebäuden
>>> 
>>> Stuttgart – München – New York – Paris
>>> 
>>> Geschäftsführer :Diplom-Ingenieur Matthias Schuler,
>>> Diplom-Ingenieur
>>> Thomas Auer, Diplom-Physiker Stefan Holst, Diplom-Betriebswirt
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>>> Schnelle
>>> 
>>> Eingetragen beim Amtsgericht Stuttgart HRB 23347,
>>> 
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>>> 
>>> -----Ursprüngliche Nachricht-----
>>> Von: TRNSYS-users
>>> [mailto:trnsys-users-bounces at lists.onebuilding.org]
>>> Im Auftrag von Wirich via TRNSYS-users
>>> Gesendet: 24 November 2017 18:13
>>> An: trnsys-users at lists.onebuilding.org
>>> Cc: freppelw at noirot.fr
>>> Betreff: [TRNSYS-users] Problem Ventilation in TRNFLOW
>>> 
>>> Hi everyone,
>>> 
>>> I'm still encountering the same problem about ventilation in my
>>> project.
>>> 
>>> I've set all the ventilation network, and then I closed all the
>>> windows.
>>> 
>>> There is no heating device in the building.
>>> 
>>> I don't understand why, but at around 749 hours, I encounter this
>>> error:
>>> 
>>> COMIS MESSAGE  ***** ERROR *****
>>> 
>>> Flow matrix is singular ! This might be caused by a zone that
>>> has no
>>> 
>>> ventilation at all in this condition.
>>> 
>>> Age of air and air change efficiency output is invalid !
>>> 
>>> And this occurs until the end of the simulation, though the
>>> simulation
>>> runs until the end. I only found that when I opened the .cer file.
>>> 
>>> Moreover, when I put a heating device in a room, with limited
>>> power,
>>> the simulation stops before the end, saying that convergence was
>>> not
>>> reached. Do you think this is related to the COMIS ERROR I showed
>>> just
>>> before?
>>> 
>>> If someone can help me, I attach all my project to this mail, with
>>> an
>>> illustration, in order to better understant what I did. I used
>>> TRNSYS17.
>>> 
>>> Thank you in advance.
>>> 
>>> King Regards
>>> 
>>> Wirich
>>> 
>>> PhD student
>>> 
>>> Laboratoy of innovative technologies, University of Picardie Jules
>>> Vernes Avenue des Facultés, Salouël
>>> _______________________________________________
>>> TRNSYS-users mailing list
>>> TRNSYS-users at lists.onebuilding.org
>>> 
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