[Julian121]

As I said in my previous post, I am simulating a type of vane recessed casing treatment.
I used solidworks to design the casing treatment and the vanes. Then, I used design modeler and used boolean function to create flow domain around the vanes.
The vane have been selected as solid and the rest of domain have been selected as fluid.
I used meshing to create mesh around the vane with default setting.
As soon as the simulation starts, the isolated region error appears and the simulation stops.
The isolated volumes in cfd-post shows that there exist two isolated volumes on both sides of the vanes.
I have defined an interface between the casing treatment and the shroud in addition to define wall boundary for all sides of the vane and casing treatment.
My question is: should I define any other interface to fix the problem?

[ghorrocks]

I do not understand what that image shows.

The isolated volumes error simply means you have a domain which is unconnected to the other domains. If they were intended to be connected, then the error says you missed an interface.

Also - are you modelling the vanes? Or are the vanes not modelled and exist as cut-outs in the fluid domain? You should only model the vanes if you intend to do heat transfer modelling on them.