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Fluid Flow with Compressible Mesh

Posted Jun 5, 2012, 2:08 p.m. EDT Fluid & Heat, Mesh, Studies & Solvers, Structural Mechanics Version 3.5a 4 Replies

Mychal Smith
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Everytime I go to solve I get this message:

" Error:
Failed to find consistent initial values.
Last time step is not converged."

I've refined the mess, thats not the problem. Can someone help me out? Maybe tell me what I'm missing

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4 Replies Last Post Jun 8, 2012, 1:05 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 5, 2012, 3:31 p.m. EDT
Hi

I'm in v4.2 but I do believe i got your model loaded correctly

a few items are missing. First I would suggest that you start using one physics, ie.e. NS (disable the two others and delete your solver sequence and regenerate a new one (not that this will also delete your Results plots)

Get the NS to solve correctly then add the solid and get that one to solve with eternal forces, then add ALE and couple the three.

To add a solid domain (just now you have define a fluid (domain 1) that is also solid and that is moveing ALE that is too much for a single domain). You need another domain to call it "solid" then ypply a foundary load and get it deform, finalyy link all three.

FSI (fluid structure interactions) models can also be found in the model library of 3.5, it is worth to start following these model descriptions to learn the subtilities of COMSOL

--
Good luck
Ivar
Hi I'm in v4.2 but I do believe i got your model loaded correctly a few items are missing. First I would suggest that you start using one physics, ie.e. NS (disable the two others and delete your solver sequence and regenerate a new one (not that this will also delete your Results plots) Get the NS to solve correctly then add the solid and get that one to solve with eternal forces, then add ALE and couple the three. To add a solid domain (just now you have define a fluid (domain 1) that is also solid and that is moveing ALE that is too much for a single domain). You need another domain to call it "solid" then ypply a foundary load and get it deform, finalyy link all three. FSI (fluid structure interactions) models can also be found in the model library of 3.5, it is worth to start following these model descriptions to learn the subtilities of COMSOL -- Good luck Ivar
Mychal Smith
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Posted: 1 decade ago Jun 7, 2012, 1:33 p.m. EDT
Hey Ivar,

I did what you said and started with them separately. I sucessfully have the NS and plane stress working. The last part I need is a ALE that fluxuates on the top boundry of a rectangle or can be compressed. Any ideas?

Thanks

Mychal
Hey Ivar, I did what you said and started with them separately. I sucessfully have the NS and plane stress working. The last part I need is a ALE that fluxuates on the top boundry of a rectangle or can be compressed. Any ideas? Thanks Mychal
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
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Posted: 1 decade ago Jun 8, 2012, 12:59 a.m. EDT
Hi

check your model library there should be some mexamples, and study these how to couple the ALE (driven by u,v,w adn used for the fluid mesh geoemtry. unfortunately 3.5 is getting somewhat old for me and mine is no more up running

--
Good luck
Ivar
Hi check your model library there should be some mexamples, and study these how to couple the ALE (driven by u,v,w adn used for the fluid mesh geoemtry. unfortunately 3.5 is getting somewhat old for me and mine is no more up running -- Good luck Ivar
Mychal Smith
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Posted: 1 decade ago Jun 8, 2012, 1:05 p.m. EDT
What examples are there? I've only found the Example—Electrochemical Polishing
What examples are there? I've only found the Example—Electrochemical Polishing

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