Some day there will be some descriptions here. Meanwhile, here are two Quicktime movies.
A foam being slowly sheared. 3.1 Megabytes or 1.6 Megabytes
A foam being quickly sheared. 2.8 Megabytes or 1.9 Megabytes
Here are a few screenshots of an old version of bv:
This is the main window. You can use the arrows to move forward or back by a single time step, or play the movie continuously. You can sort of set the frame rate. You can use the slider to go to a particular frame.
This is one of the sets of options. You can specify how the bubbles are drawn, whether they are numbered, whether the bubble types (interior or boundary) are indicated, whether tagged bubbles are marked (bubbles are tagged with mouse clicks, allowing them to be tracked easily). Lines can be drawn between neighboring (touching) bubbles, and the boundaries of the foam can be marked. The boundaries aren't visible in this picture, because they coincide with the edges of the graphics region.
This is the main window again, with "numbers" turned on in the options window, and the bubble colored according to the local pressure.