ANSYS APDL Inflated Balloon Volume

AI Thread Summary
The discussion revolves around calculating the difference between the initial and inflated volumes of a hollow cylinder pressurized from the inside, modeled in ANSYS using axisymmetric shell elements (SHELL209). The user seeks to determine the centroid and area of the rectangle formed by the cylinder's lines and the Y-axis to facilitate volume calculations. Although a solution was attempted by meshing the volume with low stiffness material and using SSUM and *GET commands to output the deformed solid's volume, it proved slightly inaccurate due to ANSYS's minimum stiffness limitations affecting results. The user is looking for a more precise method to report the deformed volume, as ETABLE only provides undeformed volume data. Suggestions for commands or methods to accurately capture the deformed volume in ANSYS are requested.
Rolor
Messages
3
Reaction score
0
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.
 
Physics news on Phys.org
OK, I have created a solution to this, but it is slightly inaccurate. I meshed the volume of interest and set the material of that volume as very low stiffness. Then I ran the model and used SSUM and *GET to output the volume of the deformed solid. ANSYS has a minimum limit on the stiffness of any material, so the dummy material does influence the trial results (although only by less than 1%). I would like a more accurate solution and will be trying to create one. If anyone has any advice that would be much appreciated.
 
Actually that does not work as ETABLE (which I was using to collect the volume information) reports the undeformed volume, not the final volume. Is there a command that reports the deformed volume?
 
Back
Top