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Problems applying boundary condition on 8 node shell element

Problems applying boundary condition on 8 node shell element

Problems applying boundary condition on 8 node shell element

(OP)
I am having two problems with Ansys.

Problem #1

Imagine a simple rectangular plate with some semi-circular notches.  The plate is 4"x8"x.1".  I am using shell 93 element.  My only load is a negative (tensile) line pressure that is being applied to one of the two short edges of the plate.  The other edge is constrained from moving along the x,y, and z directions, and from rotating about the axis parallel to the edge.  I am getting an Ansys error that say something about a moment convergence that is exceeding the 1E-2 limit.  BTW, the Ansys analysis is a multi-linear elastic analysis (small deflection) w/ automatic time stepping.  Trying to do a strain life approach to figure out if the notches used to clear components will undergo problems if there is occasional plastic deformation.  The multi-linear approach is an attempt to model the cyclic stress strain curve.  This may have nothing to do with the moment convergence issue, however, it leads into problem #2 that I am having.

#2  After waiting several hours to solve a 3D (Solid 92) element problem, I am left with stresses that look to make sense, however, the needed parameter is strain, and elastic, plastic, and total strain is zero according to the post processor.  How can this be?  The only though I have is that I entered strain values that only covered 130 ksi of stress.  If the stress exceeds this value, then perhaps it will read back 0 strain on all elements.  Looking at the deformed shape animation, it is behaving like I would expect, I get stress values but I don't get any strain.

Any help would be appreciated.

Thanks

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