I can't get this model to converge in spite of having filleted the presumed-relevant corner to remove the potential singularity. It is shown here face-on to a symmetry cut after an h-adaptive loop of 8 cycles:
(The stress range for the plots was deliberately set to the yield level of the stud.) This is intended to model a bolt threaded into a pair of test blocks, using a shrink fit to simulate the threaded joints. A horizontal force is applied to the blocks, and vertical motion of the blocks is not allowed, so that the stud is bent into an "S" shape.. Only one quarter of the model is shown because I used symmetry across the X-Y plane and anti-symmetry across the middle of the stud to reduce the computational load. The full model (before the symmetry cuts) is shown here for clarity:
Here's what happens when the mesh resolution is increased using the h-adaptive default settings:
This behavior is not caused by some instability of the h-adaptive method but has been replicated with manual mesh resolutions set by mesh controls. It also has not improved by addition of the fillet; similar stress increases at the edge where the stud emerges from the block were observed without it. The stress increases without limit on the compressed side of the stud here:
...and on the upper edge of the fillet inside the hole in the block here:
These stress maxima are near the location where the interference ends between the two parts. Here are the study properties:
(I haven't tried fiddling with the "Accuracy bias" setting, nor have I tried the p-adaptive method.) Attached is a P&G in case you want to look in greater depth.
Can anyone suggest what I'm doing wrong? -- John Willett