Learning Forum

[gabriele.venturi]

Hi,

I am trying to simulate a three point bending test with a carbon fiber-aluminum honeycomb sandwich. I have done the real test in a lab and I want to compare the Force-Deformation curves to validate my FEM model. At the moment the core is modeled as a block with orthotropic properties, while the upper and lower skins are surfaces modeled by shell elements (stackups are defined with ACP Pre). I am using two fixed supports and a fixed displacement on the tester. All contacts are bonded and I manually set the shell normal orientations. I am measuring the Force with a Force Probe applied on the tester, but apparently my FEM model requires a force three times greater than the real one to get the same deformation. Any suggestions? I can upload screenshots of the simulation if needed. Thanks!

[peteroznewman]

Honeycomb core has a different modulus in the L and W directions.

Where did you obtain the orthotropic modulus values for the honeycomb core?

How do you know which direction the core was assembled into the sandwich relative to the long dimension of the bending test sample?

Which axis did you use for the L and W directions in the orthotropic material model?

Did you create a coordinate system for the material axes in the model?

Did you assign that coordinate system to the material on the core body?