Why do I get different displacement when I tread my component as solid(1.74mm) and shell(3.99mm). I tried thick formulation as well but results are the same as thin shell formulation? Am I interpreting the results in a wrong way or have I not set up the problem correctly?
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Solution ID: S-020519 - Stress stiffening (inplane effect)
The Solution compares the deflection results of a simply supported square plate under uniform side pressure. It features a series of tests to compare and quantify the membrane effect for thin plates:
Hand calculation using linear theory
Static analysis with small displacements,
Static analysis with small displacements and 'Inplane Effect' option ON,
Static analysis with large displacements,
Nonlinear analysis with large displacement.
The internal formulations are entirely different. Thin plies of solid elements, especially tetrahedrons, will under-predict bending.
The behavior of solid elements in high aspect ratio shapes is explored here,
https://www.stonelakeanalytics.com/2020/11/05/mesh-density-challenge/