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Old   August 18, 2011, 19:27
Default variable porous resistance
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sajad
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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
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Old   August 19, 2011, 00:47
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Glenn Horrocks
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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.
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Old   August 19, 2011, 05:04
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sajad
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hi.
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
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Old   August 22, 2011, 21:36
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I do not understand your question. Please post the CCL of your case as an attachment.
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