Cavitation and Ultra-Sonic Cleaning
Ultrasonic cleaning systems offer the possibility to gently clean off even small contaminations. For this purpose, ultrasonic vibration generators are attached to or in liquid baths, which generate standing waves with frequencies between 20 kHz and >50 kHz in the cleaning tank and correspondingly on the surfaces of the components to be cleaned. The phase change of the standing waves leads to a locally varying pressure field, whereby, depending on the intensity/amplitude, gas bubbles or vapor bubbles are periodically excited, ideally grow to a controlled maximum size and collapse specifically in the vicinity of the component. The resulting pressure and shear forces enable particularly intensive cleaning of the component surfaces, provided that the frequencies of the ultrasonic emitters are compatible with the structural size of the surfaces to be cleaned. The aim is to clean the component surface as uniformly and gently as possible in a predictable time with given parameters (intensity and frequency of sound generation, positioning of the components to be cleaned, size and design of the cleaning tank, choice of cleaning fluid and ambient conditions of pressure and temperature). To this end, the present research project will first identify all relevant individual aspects and associated phenomena and investigate and evaluate them on the basis of simplified configurations. In the long term, a simulation methodology is to be developed that enables prediction and optimization of the expected cleaning quality with sufficient precision under given conditions.
