Cooling slots
 

I am working on cooling a cuboid with slots drilled along its breadth. So i made a 2D version and meshed it in Gambit. It basically has SOLID portion then a thin slot for the cooling fluid and then again a SOLID portion. This is exposed to a flow of hot FLUID. Now the first SOLID portion exposed to the hot gas gets heated up but the second SOLID portion (the one after the cooling slot) does not.What I think is its because heat is not getting conducted into the second portion from the first.

Is there any way to include conduction between the two SOLID parts in FLUENT??