Re: [TRNSYS-users] Questions to Type 12

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

Michael,

> 1.)
>     
> Why does the model ignore the initial room
> temperature set as parameter 4?

there appears to be a bug in the code. I have fixed it and can send you
the new Fortran directly if you are comfortable recompiling code
yourself. If not, the fix will be in the next release. Please let me know
which you would prefer.

> 2.)
>     
> For the purpose of the deck I am currently creating,
> I need to read in the parameter 2 (overall conductance U*A) by an
> external file even though they remain to be constant. I set the parameter
> 2 to string and defined a new variable by equation to read in the value
> from the external file. But in this case the results are not the same as
> in the case of setting the value of U*A directly in type 12c. I also
> compared the result of the equation with the value supposed to be the
> right one. Could that be a problem of first time step
> manipulations?

I am not sure how you are reading the external file (Type9 perhaps) but
if so, then by the time the outputs of Type9 are set, the parameter
values for Type12 and all of the other components have already been read
in from the deck. You might instead use Type70 (Utility: Parameter
Replacement) which is designed to read an external file containing
replacement parameter information and replace it before Types have
processed it. The one potentially confusing thing about Type70 is that it
identifies the components whose parameters you want to replace by that
component's UNIT number. You can find a component's UNIT number by
looking at the "Control Cards" tool (where you set the
simulation start and stop time) and checking the "Component
Order" tab.

Cheers,
 David

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