[TRNSYS-users] Type 71 flow rate & IAM

[Jeff Thornton]

<1. The SPF test report for my evacuated tube collector gives the 'Flow
rate during test' as 119l/h.  I'm not sure how to convert this into the
"Flow rate at test conditions" in kg/hr.m2 required by the model (ie per
unit area), as the report doesn't detail what the area is where they
measure this flow rate?>

Take the 119 l/h and divide by the area of the collector that was tested;
typically gross collector area.

<2. In the Type71 example, parameters 10/11 for the no. of IAM angles are
given as 5.  The associated IAMData.dat file in the Examples directory has
7 angles.  I assume that 0 and 90 do not count?  In my SPF report I have
10 angles (0, 10, 20, etc) for which I have created an equivalent .dat
file.  Should I hence set the parameters 10/11 to 8, indicating 8 angles
plus 0 and 90 ?>

No - you should specify 10 angles for the 10 angles that you have - which
include 0 and 90 in your case.  If the example says 5 and the data file
has 7 than that is an error and should be fixed.

<3. I'm a bit confused about Parameter 9, the "Logical unit of file
containing biaxial IAM data", what does this represent ?>

In FORTRAN, each file that is opened must have a unique integer assigned
to it; the logical unit.  In the studio, this assignment is done
automatically and you don't have to worry about the logical unit
parameter.  If you were using a text editor to write your file you would
have to concern yourself with this value.

Jeff



Jeff Thornton
President - TESS, LLC

22 North Carroll Street - Suite 370
Madison WI 53703 USA

Phone: 608-274-2577
Fax: 608-278-1475
E-mail: thornton at tess-inc.com
Web: www.tess-inc.com