Solidification Process : DC Casting Application
 

Hi All

I was wondering if anybody is working on solidification process of binary alloys (Al-Mg, Al-Zn etc) using OpenFoam. My ultimate interest is to study macrosegregation (solute in-homogeneity at the scale of casting). For this I have planned a step by step procedure for development -

Simple Cavity Cases:
- Phase change modelling of binary alloys with lever rule with no driving forces (mentioned below).
- Phase change with thermal and solutal convection.
- Phase change with convection + solid globular grains nucleation and movement in the melt with appropriate drag model
- Same case as above with dendritic grains.

I have more or less managed to do these things but when I try to adapt the case to a DC casting case, I am having trouble in managing solute balance. I am seeing unphysical results in macrosegregation. The major difference between DC casting case (http://www.substech.com/dokuwiki/dok...ill_dc_casting) and simple cavity cases is the boundary conditions. I tried to use appropriate boundary conditions but looks like they do not work. I think the real issue is with the boundary conditions of p_rgh, Ul and Us. I am attaching these files.

I hope some one has some idea on how to proceed!

Cheers
Akash

I think you need to give a bit more information. This is a solver you programmed yourself, just giving us the boundary conditions for 3 out of many variables without a description of the domain you are trying to solve won't really help. Are you modelling this descending ram with moving meshes for example?

Hey

Thanks for your interest. I am unfortunately not at liberty to disclose the solver. But I will try to discuss the domain and also talk about what i am doing in the solver.

I am not using moving mesh and my domain is a simple rectangle. At top, there is inflow of liquid metal and at the bottom I draw the solid at cast velocity. There is cooling from the right and symmetry on the left (its an axis symmetric case). I am attaching screenshot of the steady state solid fraction profile. In this case, I have no driving force in form of natural convection (gravity=0.0). When I activate the driving force, I am seeing really strange macrosegregation profile. Like i mentioned before, the macrosegregation with convection was done in cavity cases and well validated. Its only for this casting case I have troubles.

When it comes to solver, I solve momentum equation for solid and liquid, species transport equation in solid and liquid, enthalpy equation and solid transport equation (gs transport).

Cheers
Akash

hey Akash , can you help me. I am new on this, I have task(simulation and macrosegregation study on DC casting) to complete it. badly, i need your help.
thank you

Hi
 

I have been trying to simulate DC Casting case lately and I am running it in a PIMLE loop. It is taking too long to get a profile, Can you help me convert it to Steady-state so that I can have a temperature profile.

I am using a little modified Solidification Master Case from (SolidificationFoam).


Please Help!!!



Awaiting your response.


Cheers