Thermal Simulation Package Simple Model

Hello there all,

I am currently doing a simple thermal simulation to see the heat profile of an IC package.

Creating a detailed package model would be time consuming so I created a block model to mimic the package instead.

My question is: Its only a simple block model so which materials thermal conductivity should I set it to be? I tried setting it to "MOLD" which has a low thermal conductivity of 0.8 and the results seems to differ by quite a lot in comparison to what it should be.

Is there any particular thermal conductivity value that I i should set it to?

Thank you in advance!