Asymmetry in the simulation

solid-solid phase transformations, influence of stresses and strains
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Ls_Thu
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Asymmetry in the simulation

Post by Ls_Thu » Sun Feb 28, 2021 7:04 am

Hi Bernd,

May I ask what causes the asymmetry during the similation (please see image1)? We have changed lots of paremeters but it doesn't work. The versions is MICRESS 6.300

Thank you so much!

Sai
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Bernd
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Re: Asymmetry in the simulation

Post by Bernd » Mon Mar 01, 2021 1:16 am

Dear Sai,

It would be interesting to know whether the asymmetry comes from asymmetric nucleation. Can you show the state (with already three phases) which still was symmetric and where it evolved from?

Bernd

Ls_Thu
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Re: Asymmetry in the simulation

Post by Ls_Thu » Mon Mar 01, 2021 2:39 am

Dear Bernd,

Sure. the evolution of the microstructure are showed in image 1 to 3. But when we decrease the thickness of the cementite (white phase), the situation is better.

Thank you so much !

Sai

Ls_Thu
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Re: Asymmetry in the simulation

Post by Ls_Thu » Mon Mar 01, 2021 2:40 am

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Bernd
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Re: Asymmetry in the simulation

Post by Bernd » Mon Mar 01, 2021 10:43 am

Hi Sai,

If growth is asymmetric despite symmetric start conditions, and on top the results depend on numerical details, then the simulation is unstable, and you need to revise the numerical parameters.
May I ask whether the current problem is linked to this earlier discussion here?

https://board.micress.de/viewtopic.php? ... =10#p2996

Bernd

Ls_Thu
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Re: Asymmetry in the simulation

Post by Ls_Thu » Tue Mar 02, 2021 7:35 am

Dear Bernd,

Tkank you for the reply !

Yes, they are the similar problems. While for the previous one, the asymmetry sometimes occurs but now it seems that we can't aviod it.

Regards,

Sai

Bernd
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Re: Asymmetry in the simulation

Post by Bernd » Tue Mar 02, 2021 3:21 pm

Are the numerical parameters you use still those which I suggested earlier to you?

Ls_Thu
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Re: Asymmetry in the simulation

Post by Ls_Thu » Mon Mar 22, 2021 6:10 am

Thanks Bernd, sorry for the delay !
It's the same problems. Perhaps we fixed it by decrease the spacing layer of the pearlite. I speculate it might be numerical problem or something wrong on the version.

Thanks again for the help !

Regards,

Sai

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