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Changing the material's Phase (state)

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Hi,

I am working on laser machining of metals and I am trying to model the process by COMSOL. What I have done is thermal modelling which shows the temperature distribution in the sample. I am wondering if it is possible to change the solid to melt when the T reaches Tm? and also same procesure for Tv? Is there anyway to define the Temperature dependent geometry and physics (I have to study the fluid flow when when the materials is molten)?

I will appreciate any help or tip.

Thanks,
--
H. Alavi

5 Replies Last Post Feb 9, 2016, 3:26 a.m. EST
Erik Bornhöft COMSOL Employee

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Posted: 10 years ago Jul 21, 2014, 11:20 a.m. EDT
Dear Habib,

one option is shown in the following example model:
www.comsol.de/model/tin-melting-front-6234

Another option can be to define the material parameters temperature dependent with a (continuous) jump at the melting point and then solve for convection/flow even when the material is solid in reality. In your model it could just have a very high viscosity so it is approximately solid and shows no movement. Keep in mind a volume heat source/sink to consider latent heat might be necessary.

Check also for conference paper about this topic:
www.comsol.de/papers-presentations?q=melt%20metal

--
Best regards,
Erik

*********************
Erik Bornhöft
Senior Technical Sales Engineer
COMSOL Multiphysics GmbH
Robert-Gernhardt-Platz 1
37073 Göttingen
Deutschland

Knowledge Base:
www.comsol.de/support/knowledgebase/browse/900/

COMSOL Blog:
www.comsol.de/blogs/
Dear Habib, one option is shown in the following example model: http://www.comsol.de/model/tin-melting-front-6234 Another option can be to define the material parameters temperature dependent with a (continuous) jump at the melting point and then solve for convection/flow even when the material is solid in reality. In your model it could just have a very high viscosity so it is approximately solid and shows no movement. Keep in mind a volume heat source/sink to consider latent heat might be necessary. Check also for conference paper about this topic: http://www.comsol.de/papers-presentations?q=melt%20metal -- Best regards, Erik ********************* Erik Bornhöft Senior Technical Sales Engineer COMSOL Multiphysics GmbH Robert-Gernhardt-Platz 1 37073 Göttingen Deutschland Knowledge Base: http://www.comsol.de/support/knowledgebase/browse/900/ COMSOL Blog: http://www.comsol.de/blogs/

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Posted: 10 years ago Jul 21, 2014, 10:24 p.m. EDT
Erik,

Thanks for comments. I have read the tin-melt front, but It is a little bit different with my case. I want to eliminate the elements of my geometry physically ( i.e: to show formation of the hole). It is kinda complicated but I think is doable.

Thanks,
--
H. Alavi
Erik, Thanks for comments. I have read the tin-melt front, but It is a little bit different with my case. I want to eliminate the elements of my geometry physically ( i.e: to show formation of the hole). It is kinda complicated but I think is doable. Thanks, -- H. Alavi

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Posted: 9 years ago Mar 9, 2015, 9:00 a.m. EDT
Hi,

I've been working on the same simulation as yours lately. Do you have any progress? Are you able to trace the interfaces between liquid-solid and vapor-liquid phases?

Would you please email me at ZCLOVEMIT@163.com if you have some ideas?

Cheers,
---------
Chi Zhang

Hi, I've been working on the same simulation as yours lately. Do you have any progress? Are you able to trace the interfaces between liquid-solid and vapor-liquid phases? Would you please email me at ZCLOVEMIT@163.com if you have some ideas? Cheers, --------- Chi Zhang

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Posted: 8 years ago Feb 8, 2016, 11:27 p.m. EST
Hi Chi,

Unfortunately i have not had any progress yet. But, I am going to start working on that problem again. do you have any idea how to tackle the issue :)? I will keep you posted as soon as I get any promising results

Good luck

Hi,

I've been working on the same simulation as yours lately. Do you have any progress? Are you able to trace the interfaces between liquid-solid and vapor-liquid phases?

Would you please email me at ZCLOVEMIT@163.com if you have some ideas?

Cheers,
---------
Chi Zhang





--
S. H. Alavi
Hi Chi, Unfortunately i have not had any progress yet. But, I am going to start working on that problem again. do you have any idea how to tackle the issue :)? I will keep you posted as soon as I get any promising results Good luck [QUOTE] Hi, I've been working on the same simulation as yours lately. Do you have any progress? Are you able to trace the interfaces between liquid-solid and vapor-liquid phases? Would you please email me at ZCLOVEMIT@163.com if you have some ideas? Cheers, --------- Chi Zhang [/QUOTE] -- S. H. Alavi

Erik Bornhöft COMSOL Employee

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Posted: 8 years ago Feb 9, 2016, 3:26 a.m. EST
Hi,

are you aware of the papers available from the following link?

www.comsol.de/papers-presentations?q=laser,melt

There also some dealing with hole formation. I guess it is worth to investigate how they did it. The one from Mr. Bachmann won the best paper award at the COMSOL conferences in Milan 2012.

--
Hope that helps!

Best regards,
Erik

*********************
Erik Bornhöft
Senior Technical Sales Engineer
COMSOL Multiphysics GmbH
Robert-Gernhardt-Platz 1
37073 Göttingen
Deutschland

Knowledge Base:
www.comsol.de/support/knowledgebase/browse/900/

COMSOL Blog:
www.comsol.de/blogs/
Hi, are you aware of the papers available from the following link? https://www.comsol.de/papers-presentations?q=laser,melt There also some dealing with hole formation. I guess it is worth to investigate how they did it. The one from Mr. Bachmann won the best paper award at the COMSOL conferences in Milan 2012. -- Hope that helps! Best regards, Erik ********************* Erik Bornhöft Senior Technical Sales Engineer COMSOL Multiphysics GmbH Robert-Gernhardt-Platz 1 37073 Göttingen Deutschland Knowledge Base: http://www.comsol.de/support/knowledgebase/browse/900/ COMSOL Blog: http://www.comsol.de/blogs/

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