[TheoK]

Hello all and sorry for the long post. I am currently an undergraduate student, new to CFD, trying to finish his thesis. That requires meshing the model in ICEM and simulating an air to air cross flow heat exchanger with 10 cylinders (9 interior cylinders and 1 exterior (adiabatic)), each one inside another in FLUENT.

I am using the volume and part meshing (octree), so I get a mesh with 10 solid volume meshes (for the cylinders) and 10 fluid volume meshes (for the air). My question is, should I delete the solid volume meshes, and how can I generate a thermal resistance in their place?

Also should I create a single part for the fluid volume mesh (cause it's all air), or should I keep two different streams (hot & cold)?

I am asking all these, cause I'm trying to simulate it in FLUENT, and if I don't combine the fluid volumes into 1 part, the program splits the surfaces into 2 parts (for example: wall-1 and wall-1:0.05).

Thanks in advance