Abstract

The purpose of this study is to clarify experimentally the influence of streaming induced by ultrasonic vibration on heat transfer using a horn-type ultrasonic vibrator. A horn tip of 6 mm diameter and 60.7 kHz resonant frequency was used as the ultrasonic transducer. Heat transfer experiments for a downward-facing horizontal heating surface with ultrasonic vibration from below were carried out in a natural convection region. The acoustic jet in the water from the horn tip of the transducer regarded as a nozzle exit was induced by this transducer, and as a result, up to a ten-fold increase in heat transfer coefficient was obtained by application of 20 W in both tap water and degassed water. It was found that the mechanism of heat transfer enhancement by ultrasonic vibration in tap water can be classified into four categories. In degassed water, heat transfer enhancement is influenced not by the acoustic jet, but by small-scale perturbations by cavitation microjets.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.