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sajad_abasi August 18, 2011 19:27

variable porous resistance
hi to all

is it possible to change porous resistance by time?
i use a "CEL expression" in form of "if(t<0.08[s],20000[m^-1],100000[m^-2] *t)"
but it gives me that the dimenssins are inconsistent....

what is the problem?
best regards

ghorrocks August 19, 2011 00:47

The units of your expression are inconsistent. Before 0.08s it evaluates to 20000[m^-1], and after it evaluates to 100000[s m^2]. You need to fix your expression up and it should work fine.

sajad_abasi August 19, 2011 05:04

your right it works.thanks
i have another quastion.i define an "AV" by name of "cvr" then i give value of "20000[m^-1]" then i set the resistance of porous domain by expression and equal to "cvr",i iterate it it gives me q1 which is flowrate.then i set the value of "cvr" equal to "cvr" instead of "20000".actually they are equal.

but when i run it fives me another q2.

im really confused

ghorrocks August 22, 2011 21:36

I do not understand your question. Please post the CCL of your case as an attachment.

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