Hi @ricardo,
I assume you just want the facade surface temperature and not the temperature of the fin? That makes the simulation somewhat easier, including the fin temperature will up the complexity.
For the external comfort workflows HB does a great job of demonstrating difference in surface temperature due to solar exposure and material choice, from what I understand this is effectively a very similar study.
I can’t find any topics to hand, but there have been some recent discussions on this. The key element is to split your facade surface into a grid of smaller surface so that HB can simulate solar exposure and temperature for each element of the grid. You’ll also need to consider the Shadow Calc methods and other parts of the set up so that you’re happy with the assumptions of the model - likely you’ll need the update method to be to timestep is one aspect that comes to mind.
Hope this puts you on the right path
EDIT
The discussion I was thinking of was on one of your previous posts 