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variable integration during solving?

Posted 7 ott 2011, 06:31 GMT-4 Studies & Solvers Version 4.2 1 Reply

David Segal
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Hi

I would like to define a variable to be an integral of another variable (integration to be carried over a specified cut

plane) in a 3D model during solving. In other words it would be nice if I could define an expression such as

var1 (z)=integ (var2)dxdy meaning that the integration should be carried over the xy cut plane at z

Is it possible to define the necessary expression? Would I have to resort to Matlab?

thanks

David
1 Reply Last Post 11 ott 2011, 07:46 GMT-4
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
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Posted: 1 decade ago 11 ott 2011, 07:46 GMT-4
Hi

from my undersanding that is the purpose of the "Definition - Model Coupling _ Integration" is for
You then define a "Definition - Variable" var1 = intop1(var2)

now you must define if it is on a boundary or a domain or edge for 3D, 2D, 1D and note the dx*dy*dz are "implicit"

You have also the projection integration operators to reduce or to increase the dimension

Try it out on a simple model first (i.e. 2D thermal) to get "hands on" quickly, then apply to your general case

--
Good luck
Ivar
Hi from my undersanding that is the purpose of the "Definition - Model Coupling _ Integration" is for You then define a "Definition - Variable" var1 = intop1(var2) now you must define if it is on a boundary or a domain or edge for 3D, 2D, 1D and note the dx*dy*dz are "implicit" You have also the projection integration operators to reduce or to increase the dimension Try it out on a simple model first (i.e. 2D thermal) to get "hands on" quickly, then apply to your general case -- Good luck Ivar

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