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Modeling & Meshing

Modeling & Meshing

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  3. Is any mass associated with the in-plane rotational DOF for SHELL181?

Is any mass associated with the in-plane rotational DOF for SHELL181?

Tagged: 17, beams-and-shells, mechanical-apdl, modeling-and-meshing, structural-dynamics, structural-mechanics
    • March 17, 2023 at 9:00 am
      FAQFAQ
      Participant

      No, the mass associated with the in-plane rotational DOF (ROTZ) is set to zero. SHELL181 does not have physical stiffness for the in-plane rotational DOF (i.e., drilling DOF). To deal with arbitrarily oriented shells, a small drilling stiffness is used. However, the stiffness is very small, so any mass associated with the drilling DOF could produce spurious modes (SQRT(k/m)). Therefore, ANSYS removes the mass associated with the in-plane rotational DOF.

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