In Comsol the modelling of phase change is rather simple, but it should be noticed that the model becomes strongly non-linear, so eventhough modelling is easy, solving the model is something that will result to be a bit more hard.

The easiest way to take into account the latent heat of fusion is by including it in the heat capacity coefficient which will then become very large in near the melt temperature. For that, it is essential to introduce a transition interval (temperature range in which the phase change occurs) which in case of alloys is usually the case, but in case of pure materials is something artificial. Usually, the latent heat is introduced in the CP as a Dirac function and actually Comsol has standard Dirac and Heaviside function definitions, defined as flsmhs, flc1hs and flc2hs (3 Heaviside functions) and adding letter d (of derivative) like fldsmhs turns it into Dirac functions. Comsol has an example model in its documentation showing the continuous casting process in which the solification of the metal is implemented. You can also check some of my publications on modelling of the welding or cladding process in which we use and describe the method in some more detail.

Hi

please look into attached file

Some techniques include:

-using element death or birth. Tutorial on that you can find here: http://www.mece.ualberta.ca/tutorials/ansys/AT/BirthDeath/BirthDeath.html

- You can also make loop over time steps and for each time step you can update material properties based on some key calculations you can do with the results of the previous time step.

In Comsol the modelling of phase change is rather simple, but it should be noticed that the model becomes strongly non-linear, so eventhough modelling is easy, solving the model is something that will result to be a bit more hard.

The easiest way to take into account the latent heat of fusion is by including it in the heat capacity coefficient which will then become very large in near the melt temperature. For that, it is essential to introduce a transition interval (temperature range in which the phase change occurs) which in case of alloys is usually the case, but in case of pure materials is something artificial. Usually, the latent heat is introduced in the CP as a Dirac function and actually Comsol has standard Dirac and Heaviside function definitions, defined as flsmhs, flc1hs and flc2hs (3 Heaviside functions) and adding letter d (of derivative) like fldsmhs turns it into Dirac functions. Comsol has an example model in its documentation showing the continuous casting process in which the solification of the metal is implemented. You can also check some of my publications on modelling of the welding or cladding process in which we use and describe the method in some more detail.

Thanks a lot to all for the valuable inputs

I have a model based on finite diference method to predict the heat transfer during solidification of phase change material. you can downlad the software from:

http://uidm.estg.ipvc.pt/htsmb/

You can also use these two papers:

Article Solutions for Heat or Cold Discharge from Encapsulated Phase...

And also this paper

Article Numerical solutions for mixed controlled solidification of p...

Thanks a lot Nuno Vitorino - I will check both of your papers

FLUENT:

(1) ANSYS Fluent Tutorial: Analysis of Melting and Solidification of Phase Change Material (PCM)

https://www.youtube.com/watch?v=4qTnt0B3dOY

(2) Melt/Solidification: Developing 2D from 3D geometry ( Part 1)

https://www.youtube.com/watch?v=rn6YZwv_lZE

Melt/Solidification: Simulation & Post-Processing ( Part 2)

https://www.youtube.com/watch?v=5_MKJSRd6jQ

(3) Phase change material (melting simulation ) in Fluent ANSYS

https://www.youtube.com/watch?v=4ZgxnS78dw8

Hi,

Kindly attached a zipped folder containing a project I've done on the melting and solidification of a PCM with Nano-Graphene particles.

You can view the geometry, material properties and settings I used for the simulation.

I hope it helps!