Interface Fluent issues
 

Hi guys, first of all warning you that English is not my first lenguage, so forgive me if i write somethig with no sense.

I've been trying to resolve this problem a couple of weeks, with not so much success. I have a heater, it have very complicated geometry, but i managed to mesh it with a skewness no superior to 0.98. The problem is i dont understand the interface that fluent created between the solid (Steel) and the fluid (Air), and i belive that interface is the cause of my divergence in the temperature.

As you can see in the pictures i have a src and trg interfaces, that i use to create a mesh interface, that mesh interface give me 4 more boundary conditions an these are the ones which dont undertand, what am I supposed to do with them?

can that interface really cause me the temperature divergence?

Thank you all.
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