Abstract

Ultrasonic treatment (UST) provides a scalable, non-chemical solution for improving material quality. Its effectiveness is driven by two core physical mechanisms: acoustic streaming, which enhances thermal and compositional uniformity, and acoustic cavitation, which generates localized high-energy events that promote phase fragmentation. To maximize these effects, a Modulated Multifrequency and Multimode (MMM) ultrasonic system has been developed. This advanced approach allows real-time frequency modulation, effectively eliminating standing waves and ensuring a uniform acoustic field throughout the medium. This presentation showcases recent advances in MMM-based ultrasonic processing, with applications in casting and agro-food. The MMM approach significantly enhances process efficiency, improves material performance, and contributes to more environmentally sustainable practices.

Dr. Hélder Puga is an Associate Professor with Habilitation in the Department of Mechanical Engineering at the University of Minho, Portugal. His research focuses on developing advanced ultrasonic technologies to improve manufacturing processes, particularly emphasizing ultrasonic-assisted liquid metal treatment and hybrid manufacturing strategies that combine additive and subtractive methods. He has recently expanded his research to include applications of ultrasonic technology in the agro-food sector, concentrating on enhancing seed germination and promoting early-stage plant growth. He has published over 110 peer-reviewed journal articles and conference papers in metallurgy, sonoprocessing, and sonochemistry.