The Numerative blog is currently under construction. I have, however, written a number of blog posts on the COMSOL website which are linked below.
This COMSOL blog is an introduction to the various standards used to define the material properties of piezoelectrics, with a particular focus on quartz.
This COMSOL blog explains how to define particular crystal cuts of piezoelectric materials using the COMSOL user interface.
This COMSOL blog introduced the Molecular Flow module. As the main developer for this module, I defined the physics settings for a re-purposed version of the heat transfer code to model molecular flows.