I take it your mixer is a counter-acting double shrouded turbine mixer, seeing that there are two "disks"?

Here's an interesting presentation:
http://www.slideshare.net/ileubner/s...ical-engineers
"Press the little "play" buttons under the slides to see the entire presentation."

PE - for some reason the name Ingo Leubner (the author of the presentation above) sounds familiar to me. Isn't he one of your EK buddies?