Really thick shell elements
Really thick shell elements
(OP)
To all,
I am reviewing an FE model where 2.5 inch thick plate is being modeled with shell elements. Some of the elements are 0.5 x 0.5 inches. Will this produce good results? The analysis types are linear and nonlinear static. Are there practical limits to adhere to as far as shell element size versus thickness?
Thanks.
tg
I am reviewing an FE model where 2.5 inch thick plate is being modeled with shell elements. Some of the elements are 0.5 x 0.5 inches. Will this produce good results? The analysis types are linear and nonlinear static. Are there practical limits to adhere to as far as shell element size versus thickness?
Thanks.
tg





RE: Really thick shell elements
a) what type of results: displacement, stress, ?
b) your definition of "good"
c) the overall size of the plate - if it is 20 ft x 20 ft, then the results may be acceptable; if it is 1 ft x 1 ft, then you don't have a thin shell and the results will not be correct.
The real question to ask is: does the "structure" behave like a thin shell?
RE: Really thick shell elements
(Even if you do have to wait a ridiculously long time for your answer.)
RE: Really thick shell elements
Perhaps I didn't read [b]SW[\b]'s post the same way, but I think you are making the same point. I understood SW's post as trying to define "thin". IF the plate is 1'x1', then a 2-1/2" thick plate hardly qualifies for shell elements. If, however, it is 20'x20', then 2.5" may still exhibit plate/shell behavior.
The question is, "Does the shell behave like a 'thin' shell?" This question really relates to the mathematics and which theoretical basis the software will use to calculate results: thin shell, thick shell, brick?
RE: Really thick shell elements
The best way to make this kind of determination is to run a test case or two with the specific element and check the results against known solutions...(Look in text books, Roark, or other references)...
There are undoubtably practical limits, but again they will vary depending on the specific elements used and testing should be done to verify results......
Ed.R.
RE: Really thick shell elements
Live Long and Prosper !
RE: Really thick shell elements
corus