stabilization : small damper on every node (every DOF, actually)
Even though this is a static analysis, a "velocity" value is still calculated for each DOF between each substep by using the du and the dt; consequently, the larger the du/dt, the larger the stabilizing force that will be applied. This is one of the few cases in which the "time" value has any effect in a static analysis.
Because these dampers introduce artificial stabilizing forces, we need to ensure that the effect is minimal. This can be done with the /POST26 commands listed below to plot the stiffness energy (SENE) and stabilization energy (STEN) over time. If the STEN is small compared to SENE, the results are probably relatively accurate.
/post26
/gropt,logy,1
enersol,2,sene
enersol,3,sten
plvar,2,3
