i have experience with ansys a
 

i have experience with ansys and floworks, which allow easy application of the boundary conditions via gui.

i still could not figure out, for a given mesh, how i an define the boundary conditions. what tools do you use?

which books can you suggest to get deeper in this topic?

For tools, you could take a lo
 

For tools, you could take a look at autoPatch and patchTool.