[TRNSYS-users] digging into trnflow convergence problems

[Mariëlle Nuchelmans]

Are you using a thermostate or an equation to control the cooling? You should use an thermostate. An equation gives a zero or an one, so it can go off/on/off/on and your program crashes (on because it reaches setpoint and then off because wanted temperature is reached) A thermostate has a dead band and it chooses on/off after 5 iterations. It is less accurate but your program runs.

Good luck

Mariëlle

Van: frodriguezpc at labein.es [mailto:frodriguezpc at labein.es]
Verzonden: maandag 27 september 2010 9:42
Aan: Mariëlle Nuchelmans
CC: trnsys-users at cae.wisc.edu
Onderwerp: RE: [TRNSYS-users] digging into trnflow convergence problems


It crashes even at n=7 timestep... I am pretty sure it has to do with this temparature thing. A check to my lst file shows this clear pattern with lack of convergence in al the external temperature peaks, so I turned off cooling and the result is I get convergence thanks to interior temperatures going above exterior at most of the previous conflict timesteps... still there are a couple times of year where I still get higher ext. temps, and convergence problems show

Francisco Rodríguez Pérez-Curiel

TECNALIA-Construcción
Parque Tecnológico, Edificio 700. E-48160 Derio (Bizkaia) (SPAIN)
Tel. +34 94 607 33 00,  Fax. +34 94 607 33 49
francisco.rodriguez at tecnalia.com,
www.tecnalia.com

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Mariëlle Nuchelmans <M.Nuchelmans at chri.nl>

27/09/2010 09:18

Para

"frodriguezpc at labein.es" <frodriguezpc at labein.es>

cc

"trnsys-users at cae.wisc.edu" <trnsys-users at cae.wisc.edu>

Asunto

RE: [TRNSYS-users] digging into trnflow convergence problems










You could try even smaller time-steps, I've models with timestep: 0,03125 (n=5), 0,015625 (n=6) and even 0.0078125 (n=7). It just takes a while before it's finished calculating.

Kind regards,

Mariëlle


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