How to obtain resonable nodal stress values?
How to obtain resonable nodal stress values?
(OP)
Hi folks,
Since nodal stresses are not continuous across the element boundary, in what way can I obtain the resonable values? For example, average the stress values at the nodes within different elements?
Thanks a lot!
Sunny





RE: How to obtain resonable nodal stress values?
The most accurate stresses are at the element centroids
(*EL PRINT, POSITION=CENTROIDAL). If you want nodal stresses ABAQUS will provide them
(*EL PRINT, POSITION=AVERAGED AT NODES)
Of course, they are averages from adjoining elements if the element type and material properties are the same.
MRG
RE: How to obtain resonable nodal stress values?
sunny - The gauss points stresses should always be printed/output if the most accurate stresses/etc. are needed since the stresses here are obtained directly from the displacements at the nodes (third order quantity after strain) without extrapolation. If the mesh is adequate you should find little difference (say 5%) between element-averaged and nodal-averaged values anyway. In fact, this methodology is used to estimate mesh errors/norms due to high displacement gradients.
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RE: How to obtain resonable nodal stress values?
corus
RE: How to obtain resonable nodal stress values?
Centroidal stresses are generally regarded as most accurate. Well, at least when I first learnt FEA I was told/read this!
Gauss points are used to integrate stiffness matrix etc.
MRG
RE: How to obtain resonable nodal stress values?
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RE: How to obtain resonable nodal stress values?
All that Drej says is completely correct.