[TRNSYS-users] min flow rate active layer

[David BRADLEY]

Elena,
   Even in a real system, you would need to make sure that there is a 
minimum flow through the floor when there is a call for heat. Otherwise 
the flow will be laminar and you will not get any decent heat transfer 
between the fluid and the floor. I think what you will need to do in 
your simulation is to have the flow start at the minimum allowable flow 
rate when there is a call for heat and then vary up to the maximum rate. 
There is an example located in ..\Trnsys17\Examples\Feedback 
Control\SunSapce - Floor heating PID controller.tpf showing how you 
might set up your controller.
Kind regards,
  David


On 7/7/2014 07:38, elena.bee at libero.it wrote:
> Hi everyone!
>
> I hope somebody can help me with this issue…
> In active layer there is a minimum mass flow rate and it's not allowed to go
> under that value, so how can I simulate a variable system, where the mass flow
> is controlled by a thermostat and it varies linearly from zero (no heat is
> required) to 1 (maximum flow rate-project value). When the coefficient is near
> zero, the flow is too low and it gives error… Is there a solution?
>
> Thanks in advance
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-- 
***************************
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 at tess-inc.com

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