Hello @rtaheri, thanks for getting back to me.
In the end, we should be following the warnings and instructions to achieve a solution. The warning message when selecting the Conjugate Heat Transfer simulation states that facet only geometries can not be used in this simulation type. If you go back to your own CAD Software Rhino, you’ll realize that you have a mesh rather than a closed solid poly surface. You need to convert your mesh into a closed solid one.
I was able to import the following closed solid in a 3dm format, and looks like we can start working on a Conjugate Heat Transfer simulation too. Please feel free to copy the project and start working on it. I would always recommend keeping an eye on the warnings given in the platform.
I hope this will be helpful.
Best regards, Kaan