Thin walled profile in torsion

Open thin-walled rectangular cross section profile (a longitudinal cut is performed at the lateral wall center line, whose kerf (width) is negligible), 120x40mm outer dimensions, 2mm wall thickness. (Dimensions at the midsurface: 118x38mm), element size ranging from ~10mm to ~20mm.

sorgente ipe

At the A cross section, a skew-symmetry material continuity constraint is applied.

The kinematic constraint at the B point (sphere in cylinder joint) is a positioning constraint, along with the $w_A=0$ axial constraint in A.

A twist per unit length equaling 0.001 radiant/mm is imposed to the profile, i.e. a $\psi_B=0.001 \cdot l$ (it was, erroneously, $\psi_B=0.0005 \cdot l$) rotation is imposed at each end, where $l$ is the $z$ axial coordinate of the endpoints, being z=0 at the skew-symmetry plane.

The reaction moment associated with the constraint will determine the applied torque $T$.

modello iniziale

profile geometry alone

marc_element_classes.pdf

profile_in_torsion_a2019_v001.mfd

profile_in_torsion_a2019_v002.mfd

profile_in_torsion_a2019_v003.mfd


nolimetangere