chtMultiRegionFoam + Custom boundary condition at solid-fluid interface
 

Hello Everyone,

I am simulating laminar flow in a microchannel with conjugate heat transfer between the channel walls and the fluid.

I used chtMultiRegionFoam and was able to simulate it successfully, with good agreement to analytical correlations for friction factor and Nusselt number.

Now, I want to add electrohydrodynamics to the problem. I have successfully added the electrostatic equations to the solver and was able to validate with the cases presented in [1]

The case in Ref [1] considers the electric potential to be applied in the outer walls, which I could apply using the regular method to define the boundary conditions.

In my actual problem, I want to apply electric potential and charge injection at the interface of solid and liquid. To be specific, I want to define two new patches (emitter and collector electrodes) along solid-fluid interface and then set the boundary condition for charge density and electric potential on these patches.

Kindly, please give some directions on how to define new patches on solid-fluid interface in chtMultiRegionFoam.

Thank You.

-Pavithra.


[1] https://link.springer.com/article/10...404-015-1581-5

Let me try to elaborate more on my requirement.

I have a liquid layer on top of a solid layer. Thin plate electrodes (with negligible thickness) are flushed on the top surface of the solid layer. Thus, I have to apply boundary and initial conditions on the thin electrodes that exactly coincide with the solid-fluid interface.

I have attached a schematic of my problem.

How can I create these electrode patches and setup a boundary condition on these patches ?

Hello,
Not sure thermal baffles can help you.
https://openfoam.org/release/2-3-0/t...#createBaffles
And here is other thought: $FOAM_TUTORIALS/combustion/fireFoam/les/oppositeBurningPanels --> Here patches are created as per the requirement using createPatch command.
Hope it helps

Thank you

Hi Kumaresh,

Thanks for the suggestion. After your suggestion, I looked at some tutorials where similar approach based on thermal baffles have been utilized. I hope my requirement could also be met out using the same approach. Will try it (next week) and update the outcome, here.

Thank You.

Hi,

I was able to meet my requirement by a second topoSetDict. As u said, baffles can also be used to achieve it. But toposet and createPatch was a simpler solution.

Thank You.

chtmultiregionfoam with cooling channel
 

Hi Pavithra,

Since you have experience in using chtmultiregionfoam for cooling channel simulation, I presume you might be able to help me. My original post is in the tread: https://www.cfd-online.com/Forums/op...l-cooling.html

I'd really appreciate your help.

Thanks