Hi Arjan Gelderblom
Sorry about the delay in answering, I was “on the road”, e.g., presenting at NAB New York.
Here is a scene file that should resemble what you need, fingers crossed:
Scene file
https://www.amazon.com/clouddrive/share/1RUJll5MMBhDwWFIYKlsG9C2OkOoh8kLMgD1VEet8WD
I believe that 00:12 [min:sec] in the clip is the part you are looking for a solution.
I have used a Boole, for the side that has no heat, if that is not really how it should work, the Boole is not needed for the animation.
Here is a version without Boole and some other settings:
Scene file
https://www.amazon.com/clouddrive/share/eIFGt5cGKsSvMrGZHLQq5kbXzgod6894GOrG358omQa
Please let me know if that works for you.
All the best