The thin-walled cylinder with a hemispherical cap under internal
pressure as four axisymmetric quad8 blocks: axial stress on the outer
surface at D 25.283.
The NAFEMS target, 25.86, is the axisymmetric thin-shell solution; our
solid model converges to 25.27, the value ESRD reports for its converged
axisymmetric solid. So the NAFEMS quantity keeps a 1% tolerance and is
a known failure until there is an axisymmetric shell element, and a
second quantity checks the model against the solid reference (pass,
0.05%).
Part of #97.