Generate hex mesh for CHT in Ansys Meshing
 

Dear CFD community,
I am currently working on CHT simulation and I'm currently struggling with Ansys meshing. This is the first time I've used this mesher (I previously used Fluent meshing a lot) but I think mastering both is interesting. I followed the Ansys Learning Hub course but unfortunately, for now I can't get my head around this mesh...
You will find just after an overview of the fluid domain:
https://i.ibb.co/5ktvpRX/overview.png
To start, I have decomposed my fluid domain in different bodies and it appears that the most difficult one to mesh is the one circled in red on the previous picture and which you can see better just after:
https://i.ibb.co/rxgKJ53/focus.png
The question is then how could I mesh this difficult part with hex cells ?
It appears that the 11 parallel cavities are sweepable and therefore easy to mesh. The main issue concerns the junction between these sweepable cavities and the two rectangular slots (which cannot be swept easily). I have simplified the case to work on this specific issue and i obtain the following mesh by applying default Multizone with two bodies only consist in a cavities and a rectangular slot :
https://i.ibb.co/sKt8TtW/mesh.jpg
You notice that I avoided the pinching problem at the top of the cavity/slot intersection so as not to have this problem to deal with for the moment...
Basically, it works ! Unfortunately, when i try to add inflation layers to the previous mesh, the mesh generation fails... The error message is that inflation is not compatible with the settings so I have tried to desactivate multizone and it works very well :
https://i.ibb.co/xHbJq0q/tet-mesh.jpg
1) Consequently, how could i obtain the same mesh as previously (with an inflation layer) with hex mesh ?
2) Moreover, how can I avoid the pinching of the boundary layer at the angles circled in red in the previous image ?

THANK YOU VERY MUCH FOR YOUR HELP !

Best regards,
Pierre