Learning Forum

[Ben Leistiko]

Hi,

I am hoping to make shell elements in Ansys that accurately capture the stiffness of an isogrid sheet.  To do this, I would like to independently control the element's thickness and bending stiffness.  This is accomplished in NASTRAN using the PSHELL bending coefficient and shear ratio, where can I find the equivalent parameters in Ansys Mechanical?

Thank you,

Ben

[peteroznewman]

One way to accurately capture the stiffness of an isogrid sheet in NASTRAN is to use a PCOMP card to define two layers with two different materials and two thickness values.  One layer is for the facesheet using the facesheet thickness and the isotropic material properties for the facesheet. A second layer is for the ribs using the rib thickness and the smeared equivalent material properties for the ribs.

Ansys supports Layered Shell elements in a similar way to the NASTRAN PCOMP.  Open Ansys Help and in the Mechanical APDL section, go to the Element Reference and read details in the SHELL281 page.

Yet another way to accurately capture the stiffness of an isogrid sheet in Ansys is to explicitly model the facesheet and ribs in geometry. The advantage of this method is you don’t have to calculate the smeared equivalent material properties for the ribs.