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Set the result of one computation as the initial value of another

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Hi everyone! I am doing a simulation of the flow in a complex structure tube. I have finished the computation using k-ε as the turbulence model. Then I want to use its result as the initial value of the simulation using the Low-Reynolds number k-ε model. It is a quiet stupid question of which the answer must be in the Tutorial. But I didn't find that. Is there anyone who can explain the procedure to do that? Thank you very much!!!

6 Replies Last Post 2015年8月3日 GMT-4 22:54
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 9 years ago 2015年7月28日 GMT-4 10:20
Hi

Check the solver node: Dependent variables and the associated Help and/or DOC "Initial variables Solved For"

Try using some of the COMSOL internal combined solver cases as shown herebelow for solid

There is NO restriction that both solver cases must be under the SAME study


--
Good luck
Ivar
Hi Check the solver node: Dependent variables and the associated Help and/or DOC "Initial variables Solved For" Try using some of the COMSOL internal combined solver cases as shown herebelow for solid There is NO restriction that both solver cases must be under the SAME study -- Good luck Ivar


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Posted: 9 years ago 2015年7月31日 GMT-4 03:54
I am so grateful that you have replied to my question! That was very useful. Besides, I am still not sure if my setting is correct because I still can't get the result.

I have set two turbulence model with the same boundary condition. Then I use to steps of stationary calculation in one study. In the second step, I set the "initial values for variables solved for" as follows:
Method: Solution
Study: Study 1
Stationary Solution: Current
Use: Current
Selection:Automatic

And I have tried also to use these two models in two study.
In the second study, I set:
Method: Solution
Study: Study 1
Stationary Solution: Solution 1
Use: last
Selection:Automatic

Are they correct? Sorry for bothering you again!
I am so grateful that you have replied to my question! That was very useful. Besides, I am still not sure if my setting is correct because I still can't get the result. I have set two turbulence model with the same boundary condition. Then I use to steps of stationary calculation in one study. In the second step, I set the "initial values for variables solved for" as follows: Method: Solution Study: Study 1 Stationary Solution: Current Use: Current Selection:Automatic And I have tried also to use these two models in two study. In the second study, I set: Method: Solution Study: Study 1 Stationary Solution: Solution 1 Use: last Selection:Automatic Are they correct? Sorry for bothering you again!


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Posted: 9 years ago 2015年8月3日 GMT-4 00:02
What do you mean you cannot get a result? Does it not converge or do you not get what you expect?

Mark
What do you mean you cannot get a result? Does it not converge or do you not get what you expect? Mark

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Posted: 9 years ago 2015年8月3日 GMT-4 00:15
Yes, I mean that it doesn't converge.
Yes, I mean that it doesn't converge.

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Posted: 9 years ago 2015年8月3日 GMT-4 00:15
Yes, I mean that it doesn't converge.
Yes, I mean that it doesn't converge.

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Posted: 9 years ago 2015年8月3日 GMT-4 22:54
what is the error message when you separate it out into two different studies?
what is the error message when you separate it out into two different studies?

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