I dont know if it helps
Ultrasound waves generate a rapid succession of compression and decompression phases in the cleaning tank. The temporary but extreme compression shatters the countless, microscopically small bubbles which have built up and so generates high-energy turbulence over the workpiece. The result is highly intensive, thorough cleaning. At the same time, pulsating micro-flows carry off particles of dirt and feed in fresh cleaner continuously.
Perfect ultrasound cleaning calls for a liquid medium which transmits the sound waves easily, keeps dirt in solution and prevents it re-adhering to the workpiece.
Alan