I feel like this should be a fairly easy problem to solve in ANSYS but can't work it out. My actual problem is a bit more complex that what I've written below, but the solution method should be the same. A hollow cylinder is pressurised from the inside, the cylinder inflates. What is the difference between the initial interior volume and the inflated volume? The cylinder is modeled using axisymmetric shell elements (SHELL209) so is only made of three lines. Conceptually these are swept around the Y-axis to create the cylinder, however the initial model and the solved model are just displayed as lines as the shape is not swept prior to or during solving. All I need to know to calculate the volume is the centroid and area of the rectangle enclosed by these lines and the Y axis. How can I find these? Thanks for any help.