A translation of a 1999 paper by Takaaki Matsumoto directly relates to current observations in ULTR and other experiments.
Please review the following Project videos parts.
Microscope session (3 Mar 2018)
Part of presentation at Sochi 2018 (4 Oct 2018)
Thomas Kaminski ULTR experiments Late November 2019
https://photos.app.goo.gl/e2jtdN5QdzEAedhM6
https://photos.app.goo.gl/jDofUr8EKGhn6eD17
References
T. Matsumoto, “Discovery of Micro Tornadoes” Proc. of The Autumn Meeting of Japan Atomic Energy Society, Niigata Inst. of Technol., p. 163, (1999).
The structures and evolution of Smoker in an ultrasonic field https://www.sciencedirect.com/science/article/pii/S135041771200003X#b0005
here is a paper on Bubble structures in acoustic cavitation https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.457.1993&rep=rep1&type=pdf