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Integration over a filtered volume
Posted Apr 30, 2012, 1:19 p.m. EDT Geometry, Parameters, Variables, & Functions, Results & Visualization Version 4.0a, Version 4.2a 2 Replies
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I kindly ask you to help me to solve the following problem.
I am able to plot a user-defined quantity with an element filter in a 3D domain: the logical expression I use for the filter of this quantity is :"quantity>0".
Then, my 3D domain is "restricted" to the only elements where this quantity is larger than zero.
My question is: how can I do a volume integration in this "restricted" 3D domain?
I am not able to identify this restricted 3D domain as a specific entity, but I am only able to plot it.
Please, help me to fix this problem.
With my best regards,
Alessandro
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Try it out on a simple example: i.e. a cylindre, centred on the 0,0 for the axis and aligne along z, if you integrate over the domain thevalue "1" you should get the full volume. If you integrate "1*(x>0) you should get the half volume for X>0. Tis is indendet if you select one or several domains.
If you integrate a quantity as a power density Q, using theoperand Q*(Q[1/W]>1) will give you the integration over all selected domains where Q>1.
Note: take care with the "average" operator, if you use bolean operations you will probably get wrong results, as it normalises over the domain(s) but without the boolean operation, and probably your normalisation ovlume is too big !
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Good luck
Ivar
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