[TRNSYS-users] Solar collectors

[Matteo DF]

> I'm not sure I understand what you mean about relative parameters. The sign
> of the parameters is typically built into the model so you provide positive
> values and the model knows that the form of the equation is
>
> n0 - a1*(Ti-Ta)/Gt - a2*(Ti-Ta)^2/Gt.
>
> The one thing you must be careful about is that standards for the efficiency
> equation differ. Sometimes efficiency is based on T inlet minus T ambient.
> In other countries it is T average minus T ambient. Check the "More" button
> next to each parameter and you'll get additional information about
> specifically what the parameter is intended to do and what assumptions are
> being made.

Dear David,

Ok, this is clear... The "relative" was probably a traduction error
from my italian to your english; probably I should replace "relative"
with "corresponding" :)
So now I know these two different standard, and if I look to the
standard used in my datasheet, it is the "wrong" one, namely the one
not used by trnsys.
I should have a look to other datasheets to find these values in the
right standard.

The other question was about the best configuration for my 12 m^2
array... Are you saying that I should use a single type 1 and set the
total collector area to 12 m^2? Now I'm using the solution provided in
the attached image... Each type has a total collector area of 4 m^2,
so the total is still 12...
Which is the best solution?

Thanks again,
Matteo.
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