Post-processing can be the most satisfying part of the modeling process.  If for no other reason than that it means you are almost done!  And, of course, this is where we are able to view and interrogate our hard-earned solutions in full color.  COMSOL already provides a broad toolset for visualizing your data pretty much however your heart desires and every release sees even more and better functionality.  Recently, we discovered a really nice improvement in v5.2 relating to Filters.

You are probably aware that we can always limit the Selection of our data sets before visualizing to essentially hide domains we don’t want to see, but how do I see inside a 3D domain?  Well, this is a great use of the “Filter” subnode.  Most plot types allow you to provide this Filter subnode to limit the information plotted using a logical expression.  And, just released in v5.2 the Filter feature has become even nicer to use!

Consider the following Plot of the von Mises stress in a static loaded metal bracket.

What if we were interested in seeing the stress inside the bracket along the y=0 plane in this 3D volume plot?  There is no boundary on this plane, but we can add a Filter subnode to the plot and set the Boolean expression to y>0 so that only elements with y-coordinate greater than 0 will be visualized.

(Note:  This technique will not give the desired result if used on a Surface plot. Since by definition the Surface plot only gives results on existing boundaries.  Simply switch to a Volume plot to get the desired result.)

If you’ve tried to use these filters before, you may have noticed the nice improvement in Version 5.2.  There is now a  “Smooth” option for “Element nodes to fulfill expression:” which gives a very clean and smooth surface interpolation compared to the options available previously.  See comparison below.  I think you’ll agree there is a marked improvement. 

Thanks again COMSOL for continuing to add new and better features!

More to come...

The Team at AltaSim Technologies

Jeff & Kyle

Principals