How to simulate peltier element

About the development of the FEM module/workbench.

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kooper
Posts: 2
Joined: Thu Oct 18, 2018 12:19 pm

How to simulate peltier element

Postby kooper » Thu Oct 18, 2018 12:39 pm

Hi there,

is it possible to add a peltier element in a thermo simulation?

Regards,
Kooper
Bastiaan99
Posts: 1
Joined: Fri Nov 27, 2020 7:18 am

Re: How to simulate peltier element

Postby Bastiaan99 » Fri Nov 27, 2020 7:21 am

Hi Kooper,

how far are you with simulating a Peltiers?
I have a similar question that I require to determine how big my heatsink is going to get.


best regards

Bastiaan Pierik
raback
Posts: 75
Joined: Fri May 08, 2020 4:02 pm
Location: Finland
Contact:

Re: How to simulate peltier element

Postby raback » Sun Nov 29, 2020 4:19 pm

Hi

Elmer is interfaced in FreeCAD for some features in temperature and electrostatics so I'll answer the question as Elmer developer.

You can basically solve thermo-electric problems using weakly coupled or strongly coupled strategies for temperature T and electric potential phi. For weak coupling you still need non-standard source terms that depend on the gradient of the other term and some iteration among the equations. So whereas you might be able to define part of the case using FreeCAD to setup the case definitely it would be a challenge.

In Elmer there is also a dedicated module that solves for phi and T from a strongly coupled 2x2 system. The advantage is that it does not require any iteration. I think this was implemented for some single user and hence there is not any documentation. But if you can start from knowing that the module is ThermoElectricSolver.F90 and the only consistency case for it is called ThermoElectric then you might give Elmer a try. FreeCAD could still be used to define the mesh.

https://github.com/ElmerCSC/elmerfem/bl ... Solver.F90
https://github.com/ElmerCSC/elmerfem/tr ... moElectric

-Peter
catalyst99
Posts: 3
Joined: Mon Nov 30, 2020 12:34 pm

Re: How to simulate peltier element

Postby catalyst99 » Mon Nov 30, 2020 9:38 pm

Thank you Peter!

ok small steps first.

I’ll have to make a peltier first. Bound its cold side and place the hotside to the bottomside of the heatsink as a test?
Or just the peltier as a test?

I come from a practical approach, as therefore I have no to minimum experience with PDEs on 3d structures.Allthough I work with with peltiers in my daily life, I can understand some but cumbersome. Just Don’t hit me with curl or the inverse triangle.

So again small steps: and see if these questions can help me in simulate this in Elmer after constructing and meshing it Freecad.

I have to create a file that includes the shapes of the peltiers/TEC and heatsink. (Kiss) keep it super simple)

Do I pretend there is also thermal conductive paste between the peltiers and heatsink? Or can I neglect these?

Does the material has to have a certain roughness? Normally the peltier has some ceramic layer SiO2, how far do I have to go in simulating the peltier? I don’t know the internal properties of the peltier, or the material composition between the N or S doted materials between the SIO2 ceramics.

thanks Peter for your time,

Keep up the nice work in this community

Best regards

Bastiaan
raback
Posts: 75
Joined: Fri May 08, 2020 4:02 pm
Location: Finland
Contact:

Re: How to simulate peltier element

Postby raback » Mon Nov 30, 2020 11:44 pm

Hi Bastiaan

I would start from a rectangular block and verify that I get what I expect from an analytical calculation. If the tools are not familiar to you might even start from pure heat equation to get the workflow under control. If you want to eventually include realistic shapes, paste, heatsinks etc. you really do have a challenging problem.

-Peter