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pulsed concentration

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Hello,

I would like to give a pulsed concentration to my model. Therefore I created a rectangle function rect1.
Then I would like to declare my concentratin c_in as variable as rect1(t[1/s])*0.1 Unfortunately comsol tells me that rect 1 is an unknown variable.

How can I solve this problem?

Kind regards,

Sarah

2 Replies Last Post 6 mar 2013, 02:42 GMT-5
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 6 mar 2013, 01:01 GMT-5
Hi

where did you define the rect1 ?
in the "Global definitions - ..." or in the "Model - Definitions - Functions - rect" ...

and did you solve first and ten define your function ?, if so do an "Study - right click - Update Solution" first
Defining the solution is done high up in the node tree, compiling and getting it into the data base (Data Set) is done by the solving process

--
Good luck
Ivar
Hi where did you define the rect1 ? in the "Global definitions - ..." or in the "Model - Definitions - Functions - rect" ... and did you solve first and ten define your function ?, if so do an "Study - right click - Update Solution" first Defining the solution is done high up in the node tree, compiling and getting it into the data base (Data Set) is done by the solving process -- Good luck Ivar

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Posted: 1 decade ago 6 mar 2013, 02:42 GMT-5
Thank you, after updating the solution its working!
Thank you, after updating the solution its working!

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