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Using 2D solution as initial condition for 3d simulation

Posted Jun 22, 2012, 6:42 a.m. EDT Studies & Solvers Version 4.3 7 Replies

fcurtis
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I have a solution in 2D and have created a 3D geometry in the same file (as another model) and would like to use the solution from the converged 2D geometry as the initial condition for the 3D geometry. I feel like this task should be relatively straight forward yet I have not been able to figure it out. Any insight?
7 Replies Last Post Jun 25, 2012, 2:16 p.m. EDT
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
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Posted: 1 decade ago Jun 22, 2012, 2:35 p.m. EDT
Hi

as often I would say yes and no (more or less straight forward)
you might need to define a extrusion operator, to map the 2D results to a full 3D domain, or you use the initial conditions in such a way that you refer back to only the 2D dimensions.

--
Good luck
Ivar
Hi as often I would say yes and no (more or less straight forward) you might need to define a extrusion operator, to map the 2D results to a full 3D domain, or you use the initial conditions in such a way that you refer back to only the 2D dimensions. -- Good luck Ivar
Guoyong Sun
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Posted: 1 decade ago Jun 25, 2012, 5:00 a.m. EDT

I have a solution in 2D and have created a 3D geometry in the same file (as another model) and would like to use the solution from the converged 2D geometry as the initial condition for the 3D geometry. I feel like this task should be relatively straight forward yet I have not been able to figure it out. Any insight?


I also have the same problem, anyone submits the correct model containg the general extrusion model coupling?
Thanks a lot! About the answers from the Ivar, it is difficult to understand.
[QUOTE] I have a solution in 2D and have created a 3D geometry in the same file (as another model) and would like to use the solution from the converged 2D geometry as the initial condition for the 3D geometry. I feel like this task should be relatively straight forward yet I have not been able to figure it out. Any insight? [/QUOTE] I also have the same problem, anyone submits the correct model containg the general extrusion model coupling? Thanks a lot! About the answers from the Ivar, it is difficult to understand.
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
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Posted: 1 decade ago Jun 25, 2012, 8:54 a.m. EDT
Hi

here is an example, if you read carefully the doc and help files, and correctly interpret the order of mapping or extrusion operations it will be easier ;)

--
Good luck
Ivar
Hi here is an example, if you read carefully the doc and help files, and correctly interpret the order of mapping or extrusion operations it will be easier ;) -- Good luck Ivar

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Guoyong Sun
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Posted: 1 decade ago Jun 25, 2012, 9:44 a.m. EDT
Thanks a lot! But I can not open the document, I use the V4.2 a. Is it written in Version 4.3?
Thanks a lot! But I can not open the document, I use the V4.2 a. Is it written in Version 4.3?
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
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Posted: 1 decade ago Jun 25, 2012, 10:09 a.m. EDT
Hi

you are right that was 4.3, but you are lucky I still have a 4.2a running here it is

Do not forgget to use the solver 2 stationary node bottom: turn on the Values of dependent variables to point to the first simulation

I hope its more or less what you wanted ;)

--
Good luck
Ivar
Hi you are right that was 4.3, but you are lucky I still have a 4.2a running here it is Do not forgget to use the solver 2 stationary node bottom: turn on the Values of dependent variables to point to the first simulation I hope its more or less what you wanted ;) -- Good luck Ivar
fcurtis
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Posted: 1 decade ago Jun 25, 2012, 12:15 p.m. EDT
What I would like to do, is to take a 2-D solution and extrude it into the 3D domain. It seems your example only puts the solution on a boundary. For example, in fluid dynamics one might solve the cylinder in cross-flow in 2D and extrude that solution along the length of the cylinder (all same solution from 2D along the cylinder) as an initial condition for the 3D solution. No point in using all the compute power to get to a solution that is already found. Do you have a quick example that does that? The same HT would work.
What I would like to do, is to take a 2-D solution and extrude it into the 3D domain. It seems your example only puts the solution on a boundary. For example, in fluid dynamics one might solve the cylinder in cross-flow in 2D and extrude that solution along the length of the cylinder (all same solution from 2D along the cylinder) as an initial condition for the 3D solution. No point in using all the compute power to get to a solution that is already found. Do you have a quick example that does that? The same HT would work.
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
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Posted: 1 decade ago Jun 25, 2012, 2:16 p.m. EDT
Hi

if you look carefully I do map it to the lower surface, but I map it also to the initial conditions of the lower 3D domain. But you should be able to do the same to another BC, no ?

--
Good luck
Ivar
Hi if you look carefully I do map it to the lower surface, but I map it also to the initial conditions of the lower 3D domain. But you should be able to do the same to another BC, no ? -- Good luck Ivar

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