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Reverse problem: How to find the boundary condition iteratively if final solution is know?

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Hi everybody
I have a difficult time with comsol. I want to find the boundary condition from the known solution. If I use any programming language like matlab, we can do this using iterative method ie. we will guess the boundary condition and solve the set of equations and see if final result matches with known solution. If it does not match, we will change the guessed value and again solve the equations till it matches the known solution. Is there any way do this kind of programing in COMSOL. I use comsol3.5.
Thanks in advance.
Regards
Mahendra

5 Replies Last Post Jan 25, 2011, 6:06 a.m. EST
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago Jan 24, 2011, 5:18 a.m. EST
Hi

if you have 3.5a structural, check the example of the torque load. That is a nice example how to optimise a variable based on know load, as inverse problem using a global expression

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Good luck
Ivar
Hi if you have 3.5a structural, check the example of the torque load. That is a nice example how to optimise a variable based on know load, as inverse problem using a global expression -- Good luck Ivar

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Posted: 1 decade ago Jan 24, 2011, 7:07 a.m. EST
Thanks Ivar for you quick reply.
I dont have V3.5 structural. I am working on electrochemical module. If you can send a PDF file of the document or comsol file, it will help me a lot.
Thanks again for your reply.
Mahendra
Thanks Ivar for you quick reply. I dont have V3.5 structural. I am working on electrochemical module. If you can send a PDF file of the document or comsol file, it will help me a lot. Thanks again for your reply. Mahendra

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

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Posted: 1 decade ago Jan 24, 2011, 9:15 a.m. EST
Hi

as a user I cannot redistribute a portion of a (c) COMSOL file, but I'm sure you can get it via your local COMSOL rep. It's pages 69-74 of the 3.5a SMEUG.pdf document, the chapter of "Moments in the Continuum Application Modes"

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Good luck
Ivar
Hi as a user I cannot redistribute a portion of a (c) COMSOL file, but I'm sure you can get it via your local COMSOL rep. It's pages 69-74 of the 3.5a SMEUG.pdf document, the chapter of "Moments in the Continuum Application Modes" -- Good luck Ivar

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Posted: 1 decade ago Jan 24, 2011, 9:32 a.m. EST
Hi,

I had a similar problem last time. I attached an easy example. Have a look at global equations and Integration Coupling Variables/Boundary Variables.

The main idea is to introduce a new variable with their target function using global equations, and couple them by coupling variables to the main model.

This model imitates a dirichlet condtiion by using "common" neumann boundary conditions and the usage of a new variable.

Regards
Hi, I had a similar problem last time. I attached an easy example. Have a look at global equations and Integration Coupling Variables/Boundary Variables. The main idea is to introduce a new variable with their target function using global equations, and couple them by coupling variables to the main model. This model imitates a dirichlet condtiion by using "common" neumann boundary conditions and the usage of a new variable. Regards


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Posted: 1 decade ago Jan 25, 2011, 6:06 a.m. EST
Thank you very much to both of you.
Regards
mahendra
Thank you very much to both of you. Regards mahendra

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