title: Characterization of stable and transient cavitation bubbles in a milliflow reactor using a multibubble sonoluminescence quenching technique.
abstract: The bubble type, generated by an ultrasonic field, was studied in a batch and flow reactor using a multibubble sonoluminescence (MBSL) quenching technique with propanol and acetone. The influence of frequency and transducer configuration was evaluated using the same piezoelectric element in both setups. Results show that the bubble type not only depends on the frequency, but also on the input power or transducer configuration. Additionally, the effect of flow on sonoluminescence yield and bubble type was studied in the continuous setup at various frequencies. As the flow becomes turbulent, the sonoluminescence signal reaches a plateau for three out of four frequencies, and a transition from transient to stable cavitation occurs for frequencies below 200 kHz.
authors.affiliation: KU Leuven, Department of Chemical Engineering, De Croylaan 46, 3001 Leuven, Belgium; KU Leuven, Faculty of Industrial Engineering, Lab4U, Agoralaan Building B Box 8, 3590 Diepenbeek, Belgium.
authors.forename: B
authors.initials: B
authors.lastname: Gielen
authors.affiliation: KU Leuven, Department of Chemical Engineering, De Croylaan 46, 3001 Leuven, Belgium; KU Leuven, Faculty of Industrial Engineering, Lab4U, Agoralaan Building B Box 8, 3590 Diepenbeek, Belgium.
authors.forename: J
authors.initials: J
authors.lastname: Jordens
authors.affiliation: KU Leuven, Department of Chemical Engineering, De Croylaan 46, 3001 Leuven, Belgium.
authors.forename: J
authors.initials: J
authors.lastname: Janssen
authors.affiliation: KU Leuven, Department of Materials Engineering, Kasteelpark Arenberg 44, 3001 Leuven, Belgium.
authors.forename: H
authors.initials: H
authors.lastname: Pfeiffer
authors.affiliation: KU Leuven, Department of Materials Engineering, Kasteelpark Arenberg 44, 3001 Leuven, Belgium.
authors.forename: M
authors.initials: M
authors.lastname: Wevers
authors.affiliation: KU Leuven, Department of Chemical Engineering, De Croylaan 46, 3001 Leuven, Belgium; KU Leuven, Faculty of Industrial Engineering, Lab4U, Agoralaan Building B Box 8, 3590 Diepenbeek, Belgium.
authors.forename: L C J
authors.initials: LC
authors.lastname: Thomassen
authors.affiliation: KU Leuven, Department of Chemical Engineering, De Croylaan 46, 3001 Leuven, Belgium; KU Leuven, Faculty of Industrial Engineering, Lab4U, Agoralaan Building B Box 8, 3590 Diepenbeek, Belgium.
authors.forename: L
authors.initials: L
authors.lastname: Braeken
authors.affiliation: KU Leuven, Department of Chemical Engineering, De Croylaan 46, 3001 Leuven, Belgium. Electronic address: tom.vangerven@cit.kuleuven.be.
authors.forename: T
authors.initials: T
authors.lastname: Van Gerven
keywords: Cavitation type determination; Flow; Sonoluminescence; Ultrasonic millireactor