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Post-Processing Evaluation

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During the post processing, I would like to evaluate a variable of interest at given lengths along a given pipe (in a 2D axisym model). Lets say I want to evaluate the average concentration in a cross-section along the length of this pipe at given distances, how would I go about this? Given that it is only one geometric objecta dn thus I cannot select a boundary on which to evaluate this variable. Is this possible?

4 Replies Last Post 12.04.2012, 14:17 GMT-4

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Posted: 1 decade ago 11.04.2012, 18:36 GMT-4
Yes, it's possible. Briefly here are the main steps:
First create averaging operator: Model-Definitions-Model Couplings-Average. Then run your model.
In post-processing Results-Data Sets choose Cut Plane and create multiple cut planes a the points you are interested. Then in Derived Values-Global, choose newly created cut planes in Data Set and in the expression apply your averaging operator to the variable of interest.
Yes, it's possible. Briefly here are the main steps: First create averaging operator: Model-Definitions-Model Couplings-Average. Then run your model. In post-processing Results-Data Sets choose Cut Plane and create multiple cut planes a the points you are interested. Then in Derived Values-Global, choose newly created cut planes in Data Set and in the expression apply your averaging operator to the variable of interest.

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 12.04.2012, 02:30 GMT-4
Hi

I believe you have a second way with a projection integration operator, that creates a variable defined along an edge that comprises the integration i.i in the plane pependicular to your edge.

My experience is that one need some exercice to set up this operator, so start testing it out on a simple "square model", but it's very powerful ;)

--
Good luck
Ivar
Hi I believe you have a second way with a projection integration operator, that creates a variable defined along an edge that comprises the integration i.i in the plane pependicular to your edge. My experience is that one need some exercice to set up this operator, so start testing it out on a simple "square model", but it's very powerful ;) -- Good luck Ivar

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Posted: 1 decade ago 12.04.2012, 09:54 GMT-4
Thanks for the feedback.

I successfully created the cut planes but am still unsure about how to define and evaluate the average value of a variable on those cut planes (as a function of time). Please clarify.

PS. When creating the averaging operator (aveop1) you need to select a boundary and cannot select the newly cut planes. What exactly am I suppose to select. Also, when performing a global evaluation, I cannot select the aveop1 so what should I be selecting here?
Thanks for the feedback. I successfully created the cut planes but am still unsure about how to define and evaluate the average value of a variable on those cut planes (as a function of time). Please clarify. PS. When creating the averaging operator (aveop1) you need to select a boundary and cannot select the newly cut planes. What exactly am I suppose to select. Also, when performing a global evaluation, I cannot select the aveop1 so what should I be selecting here?

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 12.04.2012, 14:17 GMT-4
Hi

you have also an Average operator to apply on a data set, chek your right click menu, it's nly a postprocessing operation

--
Good luck
Ivar
Hi you have also an Average operator to apply on a data set, chek your right click menu, it's nly a postprocessing operation -- Good luck Ivar

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