How do i create a separation between two layers of composite on ACP (Pre)?
 

How do i simulate a delamination as an interspace or actual separation of 0.02mm between layers 3 and 4 of a carbon composite material? The delamination area is defined as 11.275x11.275mm and the centre is 163.5x163.5mm of a 225.5x225x2.05mm carbon composite plate. I have defined the area in the geometry and created it as a named selection. I am unsure what to do next, I can create the composite but I can't create the gap.