[TRNSYS-users] solar collectors

[David Bradley]

Marco,
   It could be that because the VS pump, 
collector, and heat exchanger model all neglect 
the effects of the thermal capacitance of the 
liquid in the loop that you are getting a 
numerical problem. I would suggest adding a pipe 
that has enough volume to store at least one 
timestep of fluid given your simulation time step 
and the pump's maximum output flow rate. You may 
set the losses of the pipe to 0 if you do not 
wish to consider those in your simulation.
Cheers,
  David


At 06:44 7/10/2007, Marco Zeppetella wrote:
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>Dear users,
>I’m modelling a collector loop that consists of 
>a pump (variable speed), collector(type 1a), heat exchangers

>I’ve noticed that increasing the mass flow rate 
>entering in the solar collector, the output 
>temperature increase too
 and at the contrary 
>reducing the flow rate it decrease.
>Probably I’m mistaking or not considering 
>something
 but I don’t understand what
>
>Best regards
>
>Marco Zeppetella
> 
>------------------------------------------------------------------------------------
>Marco Zeppetella
>Departamento de Investigación, Desarrollo e Innovación__I+D+I
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>Acciona Infraestructuras
>Polígono Industrial de Alcobendas
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