Re: [TRNSYS-users] Solar collectors

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

Matteo,
  The Type1 collector area is the total array area, not the module area nor the parallel area. So it should be set to 12.

And moreover, I'm takin the intercept efficiency, efficiency slope and
efficiency curvature, in a datasheet. The values are:
n0: 0.8
a1: 5.9 W/(m^2K)
a2: 0.03 W/(m^2K^2)

Should I use them as they are in the trnsys relative parameter or do i
have to correct them? (I know that I have to change the unit
measurement...)
  

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.
Best,
 David

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