[Echidna]

Hello to everybody here.
This is my first post here and this is going to be a very easy question for all of you CFD experts. I am trying to analyse a competition car rear wing on Ansys CFX. I have designed the wing in CAD software. Then i must find a way to model a main boundary around this wing to model the air around of it.
Not knowing exactly how this is done in CFX, i also designed a large cube in CAD, i put the rear wing inside this large cube and then by means of "Boolean operations" i remove the volume of the wing out of the cube's volume. So i can make a decent analysis.
But i assume that there is some feature in CFX in which this is done automatically. The problem now is that i cannot take the walls of the rear wing and everytime the outer boundary (wall) is visible, confusing the things. I hope you can help me. Thanks!