Data for further nucleation

dendritic solidification, eutectics, peritectics,....
Bernd
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Re: Data for further nucleation

Post by Bernd » Fri Aug 09, 2019 1:03 pm

I can try to make a fast fix based on the current beta-version (i.e. untested, only Linux) as soon as possible. Would this be helpful?

Bernd

CharMIC
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Re: Data for further nucleation

Post by CharMIC » Fri Aug 09, 2019 1:15 pm

that would be OK, I think. we can give it a try

CharMIC
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Re: Data for further nucleation

Post by CharMIC » Tue May 05, 2020 10:19 am

Hi Bernd,

Can the analytical_curvature option be used with the interface nucleation? how does it work in this scenario?

BR
Chamara

Bernd
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Re: Data for further nucleation

Post by Bernd » Tue May 05, 2020 8:55 pm

Hi Chamara,

The option "analytical_curvature" can also be used for nucleation at interfaces, although from a physical point of view it may not so much sense. However, for allowing nucleation at very high resolution (using a critical radius which is bigger than the grid spacing) it can be an important (numerical) tool.

Bernd

CharMIC
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Re: Data for further nucleation

Post by CharMIC » Fri May 08, 2020 4:04 pm

Hi Bernd,

how can we defined a analytical curvature if you want to use seed_density model with 1 seed class with 1nm radius?

BR
Chamara

Bernd
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Re: Data for further nucleation

Post by Bernd » Sat May 09, 2020 12:27 am

Hi Chamara,

with the seed_density model, analytical_curvature is activated by default.

Bernd

CharMIC
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Re: Data for further nucleation

Post by CharMIC » Sun May 10, 2020 9:27 am

Hi Bernd

Perhaps I was not clear.

for example if I have a seed class that has 1nm radius, how can I define a critical adius of 10nm for that seed class so that the undercooling is not so high.

Bernd
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Joined: Mon Jun 23, 2008 9:29 pm

Re: Data for further nucleation

Post by Bernd » Sun May 10, 2020 10:35 am

Hi Chamara,

I still don't get your point: If you define a seed class, what you specify is the critical radius and the seed density. So, if you want a lower undercooling, you just will define a bigger radius...

Bernd

CharMIC
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Re: Data for further nucleation

Post by CharMIC » Sun May 10, 2020 1:07 pm

Hi Bernd,

so when you defined only one seed class with 1nm radius, then the seeds will be placed in the microstrucutre with that radius. if the ame seed class was defined with 10nm radius, then seeds with the size of 10nm will be placed. however since the concentration levels are not sufficient to form such big radius then it will generate errors. so I want to define a smaller initial seed radius but define a analytical curvature with a larger radius to cut down the larger undercooling to a lower value.

Bernd
Posts: 1221
Joined: Mon Jun 23, 2008 9:29 pm

Re: Data for further nucleation

Post by Bernd » Sun May 10, 2020 4:33 pm

Hi Chamara,

This is not true. If you use the seed density model (even if only with one single class), then "analytical_curvature" is active by default, and the size of your grains will always be small (i.e. one cell with 1.01 x phHys (with phHys=phMin x hysteresis factor). The radius which has been specified for the seed class is taken as critical radius, and thus determines curvature undercooling.
This at least is as it should be - do you experience some thing different?

Bernd

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