[CFD10111]

Hi,

I am trying to find the HTCs of the midplane of a battery module. My simulation is 2D & steady state. I'm trying to input initial temperatures for the fluid and solid battery cells (see attached image for idea of geometry).

So far, I have input the fluid's initial temp in the velocity inlet BC 'thermal' tab - was this correct?

Now I'm unsure on how to input the initial temp of the solid cells (represented by squares in the pic).

Any suggestions will be much appreciated, thank you!

[LuckyTran]

Boundary conditions tabs are for boundary conditions. Your boundary conditions will be adiabatic for the adiabatic walls and coupled for the fluid-solid interfaces. No temperatures.


The initial guess you put in the initialization tab.

[CFD10111]

Hi,

Thank you for your response, it is much appreciated. I've made the upper and lower walls adiabatic. So do I not input the initial temp of the fluid in the velocity inlet BC 'thermal' tab? cause it asks me to input a temperature there.

I've also patched the battery cells to input their initial temp.

I've computed from 'inlet' in the initialization and it made the temp = velocity inlet 'thermal' tab temp.

[LuckyTran]

Sorry I did not read carefully that you were referring to the velocity inlet boundary condition. The velocity inlet definitely needs a temperature. I'm not sure I would call this an initial temperature but I hope it is clear that it is the temperature of the fluid entering the battery bank. If you put a temperature sensor on the left side outside the domain for example, what would the reading be?

[CFD10111]

No worries & that's a good point actually - I just assumed initial temp = inlet temp in this scenario, but I will double check.
I have solid battery cells (the rectangles) surrounded by fluid - I set the cells as solid & rest as fluid in design modeler. Do I need to click the 'Coupled Wall' option in 'Interface Options' for the battery cell boundaries when I'm editing Mesh Interfaces? Thank you so much!

[LuckyTran]

You don't need to choose coupled wall per se. It tags the surface and automatically sets options if you do.

Just verify that when you go to the thermal tab in boundary conditions, that you see coupled. You will have a wall and shadow-wall pair for each fluid-solid interface, both the wall and shadow-wall pair should be coupled.

[CFD10111]

Just checked and this is indeed the case. Thank you so much for your help!