Learning Forum

[Rameez_ul_Haq]

I tried conducting a simple non-linear static structural analysis for a model which only consisted of solid bodies. However, I couldn't find moment convergence plot option to track my solution. Only displacement and force convergence plot options were available.

I am already aware of the fact that the solid bodies doesn't have any rotational DOF's on its nodes and hence no moment can exist on the nodes, so does it mean that the moment convergence plot basically calculates the imbalance in the moments between the externally applied one and the internal ones on the nodes of the surface/line bodies. If yes, then what if I don't apply any external moment to my surface/line body, so what will the solver compare the internal moments to? Or now, the moment plot won't again exist.

[TomPhemmy]

Hello Rameez,
Q1. so does it mean that the moment convergence plot basically calculates the imbalance in the moments between the externally applied one and the internal ones on the nodes of the surface/line bodies
Answer: Yes. However note that externally applied moments include those you apply directly and the effect of the externally applied force and their lever arms.

Q2: If yes, then what if I don't apply any external moment to my surface/line body, so what will the solver compare the internal moments to?
Answer: The external moment will be summation of the product of all external forces and their distance to any point. This is the external moment that will be compared with the internal moment.

[Rameez_ul_Haq]

thank you for your reply. It was helpful.
Can you also please guide that does the force imbalance (for solid, surface and line bodies) and moment imbalance (for surface and line bodies only) that we see as a result of NR-Residuals are imbalances between the external forces/moments and internal forces/moments at the integration points of an element and then interpolated onto the whole element, or at the nodes of an element and then interpolated onto the whole element?
Plus, is it sensible to observe the NR-Residuals plots in my model if the moment in my model is not converging since NR-Residuals are, by definition, imbalance of the forces.