suggestion reg mesh size

[madg1]

In my work, I am required to perform FEA on really long parts and assemblies.say 100 feet hollow square sections  with cross section width 50 inches.And the plate thickness would be 1 inch.so they are really long and thin parts.

Solid meshing is considered.

so my question is there any good rule of thumb to get right mesh size.How many elements would be good across thickness of the plate?

In the above example of cross section if I get min of 3 brick elements thick, the no. of elements would be enormosly large which my comp cannot deal.

any thoughts?

[Petr.Krysl]

20-node bricks used with 2 x 2 x 2 quadrature deal with thin structures quite gracefully.  A single element through the thickness may well be enough.

Petr

[John_Holtz]

Or use plate elements.

[madg1]

john

as Petr mentioned, does so many number of solid elements along thickness doesn't matter much  reg sensitivity of results?