Hi @will_roe
The 100/1 L/D ratio (Inventor Stress Analysis, ISA) seems very large to me. Personally, I would not use a solid mesh when the L/D ratio is close to that large. But ISA does have higher order elements (high order than parabolic in Inventor Nastran), so perhaps it can compensate for such thin parts.
I suspect the 20/1 L/D ratio (Inventor Nastran) is based on the engineering approximation of thin-wall cylinders versus thick-wall cylinders.
John Holtz, P.E. Global Product Support
Autodesk, Inc. If not provided already, be sure to indicate the version of Inventor Nastran you are using!"The knowledge you seek is at knowledge.autodesk.com" - Confucius 😉
