Urgent help on ICEM CFD
 

I have problem with creating volume which has other volumes inside it. Maybe it is a subtract problem. Can anybody help me?

This is not usually a problem in ICEM CFD. But you have not even told us which mesh method you are using.

For Tetra and most unstructured methods, you just need to place material points (under create body) in each region. Flood fill will assign the materials without the need for a boolean subtraction or anything like that.

For Hexa blocking, you create material points and then split out the regions and assign the blocks to the correct material.

I thin your problem is not with meshing, i think your problem is with the model, maybe Design modeler if you are using ANSYS.

I want to create hexa or hexa-dominant mesh structure.