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 rezahemmat1985 November 11, 2012 18:04

formula

hello,
I wanna to simulate single-phase boiling in a duct via AVL Fire. I need to compute the contours of {htc(boil)+htc(convective)}. but unfortunaltely I canot do anything to compute the mentioned sum. I have heared it can be done by wrting a formula in Fire 3D plot but I canot. some one said to sum those htc in Tecplot! does any one have any idea? if yes lease tell me the procedure.Any comment is appreciated. Thanks in advance.
hint: htc(boil) and htc(convective) contours both are computed seperately.

 cschm November 22, 2012 06:40

°

Hi rezahemmat1985,

there you have essentially two ways to produce this post-processing. If you're on v2010 or later, you can put the formula into \$HOME/.avl/avl\ fire\ wm/2011/derivedQuantities. It is then applied online, no need to read your data and write the results into you 3D-Results.

If you're pre-v2010, you need to write the data into your fl3-result-file using the cfdDerive command line tool. Just look into the workflow-managers manual to learn about it's usage.

If you want to see example formulas you can look into your install dir: \$AVLAST_HOME/CFDWM/v2011.1/files/formulaExamples/AK_AttributeFormulas/cfdDerive/

There you can see a lot of examples how to postprocess the results. In essence, there are three steps:

Use the Bind() command to get the two HTC values
use strcpy(name, "ElementData:Flow:CombinedHTC:W/m^2"); to export the new values name
In the formula body, just return the two bound values.

HTH

cschm

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