Re: [TRNSYS-users] small mass flow in TABS

[David BRADLEY <d.bradley@tess-inc.com>]

Karol,

  I do not think that the problem with the matrix inversion and the low flow rate in the active layer are necessarily related. I'm not sure what to suggest about the matrix inversion. The active layer model has a minimum allowable flow rate that is based on pipe spacing, the thickness of the layer(s) in which the pipes are embedded and the area of the floor. If you want to give a lower flow rate then you need to segment the floor, which means treating the floor like it was a few floors in series. Enter the desired minimum mass flow rate in the active layer definition screen. If it is below the minimum "allowed" mass flow rate then you'll have the option to segment the floor.

kind regards,

 David

On 06/04/2018 01:58, Karol Bandurski via TRNSYS-users wrote:

Dear Experts

 

I have problem with simulation TABS with specific mass flow rate about 5.4 kg/hm2.

 

There are two errors:

1)      Specific fluid mass flow of active layer in surface  894 below minimum value of 8.90 kg/m2h Please, increase the minimum mass flow rate or use the autosegmentation feature of TRNBuild for subdividing the surface.

2)      Subroutine INVERT was called from subroutine INVPAR with a singular matrix!

 

I have increase number of loops 10 times but nothing change…

 

It is possible to do simulation with so low mass flow rate?

 

Kind regards,
Karol

 

--------------------------------------------------------------------

Karol BANDURSKI M. Sc.

Faculty of Civil and Environemntal Engeneering

Division of Heating, Air Conditioning and Air Protection

Poznan University of Technology

https://www.researchgate.net/profile/Karol_Bandurski

www.put.poznan.pl/~karol.bandurski

 

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David BRADLEY
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Thermal Energy Systems Specialists, LLC
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