FYI: the code for computing the acoustic band gaps (see [1] for basic explanation, the code linked there is obsolete though) has been updated to use the homogenization engine - this means greater flexibility in setting up the problems, as inter-dependencies among various components can be easily expressed. The examples in examples/phononic have been updated for the new code. They also present yet another way of writing problem description files.

r.

[1] http://sfepy.org/phononic/users_guide.html