User Area > Advice
Discontinuities between elements when using contours
Although nodal and element equilibrium
is achieved in a general finite element analysis, differential
equilibrium (e.g. stress equilibrium) is not necessarily
achieved at all points of the continuum considered –
most notably at the shared boundaries of elements. The reason
is given fully in finite
element equilibrium.
If such step changes are found between elements in a contour
display, the remedy is mesh
refinement. It suggests that interpolation from the gauss
points (where solution is carried out) to the nodes (where load
effects are reported) is great, i.e. the change of load effect
between one gauss point and the next is large and the assumed shape
function of the element is not able to interpolate with
sufficient accuracy. These effects are often most apparent if
"unsmoothed" contours are used.
If the results are not required at the locations in the mesh
producing these discontinuities, the effect may normally be
ignored since the load path will be correctly simulated in the
general case.
More
detailed information on finite element equilibrium
